Patchwork [RESEND:,RFC,3/3] pcie: keystone: add pcie driver based on designware core driver

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Submitter Karicheri, Muralidharan
Date March 25, 2014, 12:35 a.m.
Message ID <1395707726-20437-4-git-send-email-m-karicheri2@ti.com>
Download mbox | patch
Permalink /patch/333208/
State Not Applicable
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Comments

Karicheri, Muralidharan - March 25, 2014, 12:35 a.m.
keystone pcie hardware is based on designware version 3.65. This
doesn't support standard MSI controller and ATU port available
on newer version of the designware hardware. In keystone dw hardware
the application register space implements the legacy and MSI
irq controller registers and has registers to allow outbound and
inbound translations. So the outbound/inbound configuration is
done by the keystone pcie driver.

Driver needs to handle irq as there are EOI registers available to
ack the interrupt after the same is acked by the end point device
driver. This requires irqchip implementation for legacy and MSI
irq handling. The driver however re-uses functions from dw core
wherever possible by making their prototype available in the dw
header file and calling the same from the keystone pcie driver.

Also add dts binding documentation for configuration details.

CC: Jingoo Han <jg1.han@samsung.com>
CC: Bjorn Helgaas <bhelgaas@google.com>
CC: Kukjin Kim <kgene.kim@samsung.com>
CC: Richard Zhu <r65037@freescale.com>
CC: Shawn Guo <shawn.guo@linaro.org>
CC: Mohit Kumar <mohit.kumar@st.com>
CC: Santosh Shilimkar <santosh.shilimkar@ti.com>

Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
---
 .../devicetree/bindings/pci/pcie-keystone.txt      |   32 +
 drivers/pci/host/Kconfig                           |    5 +
 drivers/pci/host/Makefile                          |    1 +
 drivers/pci/host/k2-platform.c                     |  191 +++++
 drivers/pci/host/pcie-keystone.c                   |  860 ++++++++++++++++++++
 drivers/pci/host/pcie-ks-pdata.h                   |   19 +
 drivers/pci/quirks.c                               |   12 +
 7 files changed, 1120 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/pci/pcie-keystone.txt
 create mode 100644 drivers/pci/host/k2-platform.c
 create mode 100644 drivers/pci/host/pcie-keystone.c
 create mode 100644 drivers/pci/host/pcie-ks-pdata.h
Arnd Bergmann - March 25, 2014, 7:44 a.m.
On Monday 24 March 2014 20:35:26 Murali Karicheri wrote:
> +
> +int k2_pcie_platform_setup(struct platform_device *pdev)
> +{
> +	struct resource *phy_base_r, *devstat_r;
> +	void __iomem *phy_base, *devstat;
> +	u32 val;
> +	int i;
> +
> +	devstat_r = platform_get_resource_byname(pdev, IORESOURCE_MEM,
> +						 "reg_devcfg");
> +	if (!devstat_r)
> +		return -ENODEV;

It seems you have a distinct register set for the PHY that you are
driving here. Why not make this part generic PHY API driver?

> +static int ks_pcie_establish_link(struct keystone_pcie *ks_pcie)
> +{
> +	struct pcie_port *pp = &ks_pcie->pp;
> +	int count = 0;
> +
> +	dw_pcie_setup_rc(pp);
> +
> +	/* check if the link is up or not */
> +	while (!dw_pcie_link_up(pp)) {
> +		mdelay(100);
> +		count++;
> +		if (count == 10)
> +			return -EINVAL;
> +	}
> +	return 0;
> +}

You are blocking the CPU for up to one second here, which is really
nasty. Please find a way to move the code into a context where you
can sleep and use msleep() instead, or better use an interrupt if the
hardware supports that and use wait_for_completion().

> +
> +static void ks_pcie_msi_irq_handler(unsigned int irq, struct irq_desc *desc)
> +{
> +	struct keystone_pcie *ks_pcie = irq_desc_get_handler_data(desc);
> +	u32 offset = irq - ks_pcie->msi_host_irqs[0], pending, vector;
> +	struct pcie_port *pp = &ks_pcie->pp;
> +	struct irq_chip *chip = irq_desc_get_chip(desc);
> +	int src, virq;

Did I understand this right that the MSI implementation can be used
by any dw-pcie hardware of the same version? If so, it would be good
to move it into an extra file so it can be shared with the next host
driver that uses this version.

> +/**
> + * ks_pcie_set_outbound_trans() - Set PHYADDR <-> BUSADDR
> + * mapping for outbound
> + */
> +static void ks_pcie_set_outbound_trans(struct keystone_pcie *ks_pcie)

> +static void ks_pcie_set_inbound_trans(struct pcie_port *pp)

Why do you need to set this up from the kernel? Please move the
translation window setup into the boot loader if you can.

> +static struct hw_pci keystone_pcie_hw = {
> +	.nr_controllers	= 1,
> +	.setup		= dw_pcie_setup,
> +	.scan		= ks_pcie_scan_bus,
> +	.swizzle        = pci_common_swizzle,
> +	.add_bus	= dw_pcie_add_bus,
> +	.map_irq	= ks_pcie_map_irq,
> +};

This can just be a local variable in the probe function.

> +
> +static int ks_pcie_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
> +{
> +	struct pcie_port *pp = sys_to_pcie(dev->bus->sysdata);
> +	struct keystone_pcie *ks_pcie = to_keystone_pcie(pp);
> +
> +	dev_info(pp->dev, "ks_pcie_map_irq: pin %d\n", pin);
> +
> +	if (!pin || pin > ks_pcie->num_legacy_host_irqs) {
> +		dev_err(pp->dev, "pci irq pin out of range\n");
> +		return -1;
> +	}
> +
> +	/* pin has values from 1-4 */
> +	return (ks_pcie->virqs[pin - 1] >= 0) ?
> +		ks_pcie->virqs[pin - 1] : -1;
> +}
> +
> +
> +static void ack_irq(struct irq_data *d)
> +{
> +}
> +
> +static void mask_irq(struct irq_data *d)
> +{
> +}
> +
> +static void unmask_irq(struct irq_data *d)
> +{
> +}
> +
> +static struct irq_chip ks_pcie_legacy_irq_chip = {
> +	.name = "PCIe-LEGACY-IRQ",
> +	.irq_ack = ack_irq,
> +	.irq_mask = mask_irq,
> +	.irq_unmask = unmask_irq,
> +};

Can you use the generic irqchip code here?

> +	/*
> +	 * support upto MAX_LEGACY_HOST_IRQS host and legacy IRQs.
> +	 * In dt from index 0 to 3
> +	 */
> +	for (i = 0; i < MAX_LEGACY_HOST_IRQS; i++) {
> +		ks_pcie->legacy_host_irqs[i] = irq_of_parse_and_map(np, i);
> +		if (ks_pcie->legacy_host_irqs[i] < 0)
> +			break;
> +		ks_pcie->num_legacy_host_irqs++;
> +	}
> +
> +	if (ks_pcie->num_legacy_host_irqs) {
> +		ks_pcie->legacy_irqd = irq_domain_add_linear(np,
> +					ks_pcie->num_legacy_host_irqs,
> +					&irq_domain_simple_ops, NULL);
> +
> +		if (!ks_pcie->legacy_irqd) {
> +			dev_err(dev,
> +				"Failed to add irq domain for legacy irqs\n");
> +			return -EINVAL;
> +		}
> +	}
> +
> +	for (i = 0; i < ks_pcie->num_legacy_host_irqs; i++) {
> +		ks_pcie->virqs[i] =
> +			irq_create_mapping(ks_pcie->legacy_irqd, i);
> +		irq_set_chip_and_handler(ks_pcie->virqs[i],
> +			&ks_pcie_legacy_irq_chip, handle_level_irq);
> +		irq_set_chip_data(ks_pcie->virqs[i], ks_pcie);
> +		set_irq_flags(ks_pcie->virqs[i], IRQF_VALID);
> +
> +		if (ks_pcie->legacy_host_irqs[i] >= 0) {
> +			irq_set_handler_data(ks_pcie->legacy_host_irqs[i],
> +				ks_pcie);
> +			irq_set_chained_handler(ks_pcie->legacy_host_irqs[i],
> +				ks_pcie_legacy_irq_handler);
> +		}
> +		set_irq_flags(ks_pcie->legacy_host_irqs[i], IRQF_VALID);
> +	}

I have no idea how this would work with the standard interrupt-map property,
since the legacy interrupt host is now the same device as the pci host.

Maybe it's better to move the legacy irqchip handling entirely out of
the driver and use a separate device node for the registers so it can
come with its own #interrupt-cells, and then refer to this irqchip from
the interrupt-map.

> +	ks_pcie->clk = devm_clk_get(&pdev->dev, "pcie");
> +	if (IS_ERR(ks_pcie->clk)) {
> +		dev_err(&pdev->dev, "Failed to get pcie rc clock\n");
> +		return PTR_ERR(ks_pcie->clk);
> +	}
> +	ret = clk_prepare_enable(ks_pcie->clk);
> +	if (ret)
> +		return ret;

Could you move the clock handling into the generic dw-pcie code?

> +
> +/* Keystone PCIe driver does not allow module unload */
> +static int __init ks_pcie_init(void)
> +{
> +	return platform_driver_probe(&ks_pcie_driver, ks_pcie_probe);
> +}
> +subsys_initcall(ks_pcie_init);

Why subsys_initcall?

We should probably try to fix unloading soon.

> diff --git a/drivers/pci/host/pcie-ks-pdata.h b/drivers/pci/host/pcie-ks-pdata.h
> new file mode 100644
> index 0000000..a7626de
> --- /dev/null
> +++ b/drivers/pci/host/pcie-ks-pdata.h
> @@ -0,0 +1,19 @@
> +/*
> + * Copyright (C) 2013-2014 Texas Instruments., Ltd.
> + *		http://www.ti.com
> + *
> + * Author: Murali Karicheri <m-karicheri2@ti.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +/* platform specific setup for k2 pcie */
> +int k2_pcie_platform_setup(struct platform_device *pdev);
> +
> +/* keystone pcie pdata configurations */
> +struct keystone_pcie_pdata {
> +	int (*setup)(struct platform_device *pdev);
> +};

This should all go away once you have a proper PHY driver.

> diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
> index 3a02717..7c3f777 100644
> --- a/drivers/pci/quirks.c
> +++ b/drivers/pci/quirks.c
> @@ -3461,3 +3461,15 @@ int pci_dev_specific_acs_enabled(struct pci_dev *dev, u16 acs_flags)
>  
>  	return -ENOTTY;
>  }
> +
> +#ifdef CONFIG_PCIE_KEYSTONE
> +/*
> + * The KeyStone PCIe controller has maximum read request size of 256 bytes.
> + * Force this configuration for all EP including bridges.
> + */
> +static void quirk_limit_readrequest(struct pci_dev *dev)
> +{
> +	pcie_set_readrq(dev, 256);
> +}
> +DECLARE_PCI_FIXUP_FINAL(PCI_ANY_ID, PCI_ANY_ID, quirk_limit_readrequest);
> +#endif /* CONFIG_TI_KEYSTONE_PCIE */

You can't do this:

A quirk for a specific hardware must not be enabled by compile-time options.
You have to find a different way to do this.

	Arnd

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Thierry Reding - March 25, 2014, 10:35 a.m.
On Tue, Mar 25, 2014 at 08:44:36AM +0100, Arnd Bergmann wrote:
> On Monday 24 March 2014 20:35:26 Murali Karicheri wrote:
[...]
> > +/* Keystone PCIe driver does not allow module unload */
> > +static int __init ks_pcie_init(void)
> > +{
> > +	return platform_driver_probe(&ks_pcie_driver, ks_pcie_probe);
> > +}
> > +subsys_initcall(ks_pcie_init);
> 
> Why subsys_initcall?
> 
> We should probably try to fix unloading soon.

I did some work on this a few months ago but never got around to
cleaning up the patches. Let me see if I can resurrect that work.

Thierry
Andrew Murray - March 25, 2014, 11:46 a.m.
On 25 March 2014 10:35, Thierry Reding <thierry.reding@gmail.com> wrote:
> On Tue, Mar 25, 2014 at 08:44:36AM +0100, Arnd Bergmann wrote:
>> On Monday 24 March 2014 20:35:26 Murali Karicheri wrote:
> [...]
>> > +/* Keystone PCIe driver does not allow module unload */
>> > +static int __init ks_pcie_init(void)
>> > +{
>> > +   return platform_driver_probe(&ks_pcie_driver, ks_pcie_probe);
>> > +}
>> > +subsys_initcall(ks_pcie_init);
>>
>> Why subsys_initcall?
>>
>> We should probably try to fix unloading soon.
>
> I did some work on this a few months ago but never got around to
> cleaning up the patches. Let me see if I can resurrect that work.

I think there may be merit in these drivers using subsys_init. I've
not had time to investigate, but as far as I can remember this causes
issues with piceport.

For ARM32 host drivers, pci_fixup_irqs (arch/arm/kernel/bios32.c) must
be called before init_service_irqs (portdrv_core.c) otherwise pcieport
acts on invalid information in dev->irq and breaks. It seems that its
possible for the portbus driver to pick up new devices before bios32
has been able to fixup the irqs. Making the host bridge drivers subsys
will overcome this. I guess this hasn't been an issue in the past as
host bridge drivers were always in the arch/ directories.

In any case it may be worth testing this driver with PCIEPORTBUS enabled.

Andrew Murray
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Jason Gunthorpe - March 25, 2014, 4:54 p.m.
On Tue, Mar 25, 2014 at 08:44:36AM +0100, Arnd Bergmann wrote:

> I have no idea how this would work with the standard interrupt-map property,
> since the legacy interrupt host is now the same device as the pci host.
> 
> Maybe it's better to move the legacy irqchip handling entirely out of
> the driver and use a separate device node for the registers so it can
> come with its own #interrupt-cells, and then refer to this irqchip from
> the interrupt-map.

The other DW PCI-E drivers are being fixed to use interrupt-map, so I
think this driver should be fixed before it goes in as well.

Other PCI-E hosts have handled this particular problem with a
construction like this:

       pcie@21800000 {
               compatible = "ti,keystone2-pcie";
               device_type = "pci";
               #address-cells = <3>;
               #size-cells = <2>;
               #interrupt-cells = <1>;
	       reg = ..

               pcie_intc: interrupt-controller {
                  interrupt-controller;
		  #address-cells = <0>;
                  #interrupt-cells = <1>;
               }

               interrupts =  ... enough to decode INTx;

	       interrtup-map = <0 0 0 1 &pcie_intc 1>, // INT A
	                       <0 0 0 2 &pcie_intc 2>, // INT B
                               <0 0 0 3 &pcie_intc 3>, // INT C
                               <0 0 0 4 &pcie_intc 4>; // INT D
       }

When the legacy irq domain is created it should be bound to the
pcie_intc node, not to pcie node.

ks_pcie_map_irq should be removed.

> > +#ifdef CONFIG_PCIE_KEYSTONE
> > +/*
> > + * The KeyStone PCIe controller has maximum read request size of 256 bytes.
> > + * Force this configuration for all EP including bridges.
> > + */
> > +static void quirk_limit_readrequest(struct pci_dev *dev)
> > +{
> > +	pcie_set_readrq(dev, 256);
> > +}
> > +DECLARE_PCI_FIXUP_FINAL(PCI_ANY_ID, PCI_ANY_ID, quirk_limit_readrequest);
> > +#endif /* CONFIG_TI_KEYSTONE_PCIE */
> 
> You can't do this:
> 
> A quirk for a specific hardware must not be enabled by compile-time options.
> You have to find a different way to do this.

This configuration should happen automatically by the PCI core if the
config spaces are correct. See pcie_write_mrrs, pcie_write_mps,
pcie_bus_configure_settings, etc.

Your host will need to conform to the PCI spec and provide a root
port bridge header for this to work.

Also, even in the keystone case the MRRS should not be globally forced
like this, there may be other bridges in the system with a 128 byte
MPS.

Jason
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Karicheri, Muralidharan - March 27, 2014, 2:01 p.m.
>-----Original Message-----
>From: Arnd Bergmann [mailto:arnd@arndb.de]
>Sent: Tuesday, March 25, 2014 3:45 AM
>To: linux-arm-kernel@lists.infradead.org
>Cc: Karicheri, Muralidharan; linux-pci@vger.kernel.org; linux-samsung-
>soc@vger.kernel.org; linux-kernel@vger.kernel.org; Richard Zhu; Kukjin Kim; Mohit
>Kumar; Jingoo Han; Shilimkar, Santosh; Bjorn Helgaas; Shawn Guo
>Subject: Re: [RESEND: RFC PATCH 3/3] pcie: keystone: add pcie driver based on
>designware core driver
>
>On Monday 24 March 2014 20:35:26 Murali Karicheri wrote:
>> +
>> +int k2_pcie_platform_setup(struct platform_device *pdev) {
>> +	struct resource *phy_base_r, *devstat_r;
>> +	void __iomem *phy_base, *devstat;
>> +	u32 val;
>> +	int i;
>> +
>> +	devstat_r = platform_get_resource_byname(pdev, IORESOURCE_MEM,
>> +						 "reg_devcfg");
>> +	if (!devstat_r)
>> +		return -ENODEV;
>
>It seems you have a distinct register set for the PHY that you are driving here. Why not
>make this part generic PHY API driver?
>
>> +static int ks_pcie_establish_link(struct keystone_pcie *ks_pcie) {
>> +	struct pcie_port *pp = &ks_pcie->pp;
>> +	int count = 0;
>> +
>> +	dw_pcie_setup_rc(pp);
>> +
>> +	/* check if the link is up or not */
>> +	while (!dw_pcie_link_up(pp)) {
>> +		mdelay(100);
>> +		count++;
>> +		if (count == 10)
>> +			return -EINVAL;
>> +	}
>> +	return 0;
>> +}
>
>You are blocking the CPU for up to one second here, which is really nasty. Please find a way
>to move the code into a context where you can sleep and use msleep() instead, or better
>use an interrupt if the hardware supports that and use wait_for_completion().
>
>> +
>> +static void ks_pcie_msi_irq_handler(unsigned int irq, struct irq_desc
>> +*desc) {
>> +	struct keystone_pcie *ks_pcie = irq_desc_get_handler_data(desc);
>> +	u32 offset = irq - ks_pcie->msi_host_irqs[0], pending, vector;
>> +	struct pcie_port *pp = &ks_pcie->pp;
>> +	struct irq_chip *chip = irq_desc_get_chip(desc);
>> +	int src, virq;
>
>Did I understand this right that the MSI implementation can be used by any dw-pcie
>hardware of the same version? If so, it would be good to move it into an extra file so it can
>be shared with the next host driver that uses this version.
>
>> +/**
>> + * ks_pcie_set_outbound_trans() - Set PHYADDR <-> BUSADDR
>> + * mapping for outbound
>> + */
>> +static void ks_pcie_set_outbound_trans(struct keystone_pcie *ks_pcie)
>
>> +static void ks_pcie_set_inbound_trans(struct pcie_port *pp)
>
>Why do you need to set this up from the kernel? Please move the translation window setup
>into the boot loader if you can.
>
>> +static struct hw_pci keystone_pcie_hw = {
>> +	.nr_controllers	= 1,
>> +	.setup		= dw_pcie_setup,
>> +	.scan		= ks_pcie_scan_bus,
>> +	.swizzle        = pci_common_swizzle,
>> +	.add_bus	= dw_pcie_add_bus,
>> +	.map_irq	= ks_pcie_map_irq,
>> +};
>
>This can just be a local variable in the probe function.
>
>> +
>> +static int ks_pcie_map_irq(const struct pci_dev *dev, u8 slot, u8
>> +pin) {
>> +	struct pcie_port *pp = sys_to_pcie(dev->bus->sysdata);
>> +	struct keystone_pcie *ks_pcie = to_keystone_pcie(pp);
>> +
>> +	dev_info(pp->dev, "ks_pcie_map_irq: pin %d\n", pin);
>> +
>> +	if (!pin || pin > ks_pcie->num_legacy_host_irqs) {
>> +		dev_err(pp->dev, "pci irq pin out of range\n");
>> +		return -1;
>> +	}
>> +
>> +	/* pin has values from 1-4 */
>> +	return (ks_pcie->virqs[pin - 1] >= 0) ?
>> +		ks_pcie->virqs[pin - 1] : -1;
>> +}
>> +
>> +
>> +static void ack_irq(struct irq_data *d) { }
>> +
>> +static void mask_irq(struct irq_data *d) { }
>> +
>> +static void unmask_irq(struct irq_data *d) { }
>> +
>> +static struct irq_chip ks_pcie_legacy_irq_chip = {
>> +	.name = "PCIe-LEGACY-IRQ",
>> +	.irq_ack = ack_irq,
>> +	.irq_mask = mask_irq,
>> +	.irq_unmask = unmask_irq,
>> +};
>
>Can you use the generic irqchip code here?
>
>> +	/*
>> +	 * support upto MAX_LEGACY_HOST_IRQS host and legacy IRQs.
>> +	 * In dt from index 0 to 3
>> +	 */
>> +	for (i = 0; i < MAX_LEGACY_HOST_IRQS; i++) {
>> +		ks_pcie->legacy_host_irqs[i] = irq_of_parse_and_map(np, i);
>> +		if (ks_pcie->legacy_host_irqs[i] < 0)
>> +			break;
>> +		ks_pcie->num_legacy_host_irqs++;
>> +	}
>> +
>> +	if (ks_pcie->num_legacy_host_irqs) {
>> +		ks_pcie->legacy_irqd = irq_domain_add_linear(np,
>> +					ks_pcie->num_legacy_host_irqs,
>> +					&irq_domain_simple_ops, NULL);
>> +
>> +		if (!ks_pcie->legacy_irqd) {
>> +			dev_err(dev,
>> +				"Failed to add irq domain for legacy irqs\n");
>> +			return -EINVAL;
>> +		}
>> +	}
>> +
>> +	for (i = 0; i < ks_pcie->num_legacy_host_irqs; i++) {
>> +		ks_pcie->virqs[i] =
>> +			irq_create_mapping(ks_pcie->legacy_irqd, i);
>> +		irq_set_chip_and_handler(ks_pcie->virqs[i],
>> +			&ks_pcie_legacy_irq_chip, handle_level_irq);
>> +		irq_set_chip_data(ks_pcie->virqs[i], ks_pcie);
>> +		set_irq_flags(ks_pcie->virqs[i], IRQF_VALID);
>> +
>> +		if (ks_pcie->legacy_host_irqs[i] >= 0) {
>> +			irq_set_handler_data(ks_pcie->legacy_host_irqs[i],
>> +				ks_pcie);
>> +			irq_set_chained_handler(ks_pcie->legacy_host_irqs[i],
>> +				ks_pcie_legacy_irq_handler);
>> +		}
>> +		set_irq_flags(ks_pcie->legacy_host_irqs[i], IRQF_VALID);
>> +	}
>
>I have no idea how this would work with the standard interrupt-map property, since the
>legacy interrupt host is now the same device as the pci host.
>
>Maybe it's better to move the legacy irqchip handling entirely out of the driver and use a
>separate device node for the registers so it can come with its own #interrupt-cells, and then
>refer to this irqchip from the interrupt-map.
>
>> +	ks_pcie->clk = devm_clk_get(&pdev->dev, "pcie");
>> +	if (IS_ERR(ks_pcie->clk)) {
>> +		dev_err(&pdev->dev, "Failed to get pcie rc clock\n");
>> +		return PTR_ERR(ks_pcie->clk);
>> +	}
>> +	ret = clk_prepare_enable(ks_pcie->clk);
>> +	if (ret)
>> +		return ret;
>
>Could you move the clock handling into the generic dw-pcie code?
>
>> +
>> +/* Keystone PCIe driver does not allow module unload */ static int
>> +__init ks_pcie_init(void) {
>> +	return platform_driver_probe(&ks_pcie_driver, ks_pcie_probe); }
>> +subsys_initcall(ks_pcie_init);
>
>Why subsys_initcall?
>
>We should probably try to fix unloading soon.
>
>> diff --git a/drivers/pci/host/pcie-ks-pdata.h
>> b/drivers/pci/host/pcie-ks-pdata.h
>> new file mode 100644
>> index 0000000..a7626de
>> --- /dev/null
>> +++ b/drivers/pci/host/pcie-ks-pdata.h
>> @@ -0,0 +1,19 @@
>> +/*
>> + * Copyright (C) 2013-2014 Texas Instruments., Ltd.
>> + *		http://www.ti.com
>> + *
>> + * Author: Murali Karicheri <m-karicheri2@ti.com>
>> + *
>> + * This program is free software; you can redistribute it and/or
>> +modify
>> + * it under the terms of the GNU General Public License version 2 as
>> + * published by the Free Software Foundation.
>> + */
>> +
>> +/* platform specific setup for k2 pcie */ int
>> +k2_pcie_platform_setup(struct platform_device *pdev);
>> +
>> +/* keystone pcie pdata configurations */ struct keystone_pcie_pdata {
>> +	int (*setup)(struct platform_device *pdev); };
>
>This should all go away once you have a proper PHY driver.
>
>> diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index
>> 3a02717..7c3f777 100644
>> --- a/drivers/pci/quirks.c
>> +++ b/drivers/pci/quirks.c
>> @@ -3461,3 +3461,15 @@ int pci_dev_specific_acs_enabled(struct pci_dev
>> *dev, u16 acs_flags)
>>
>>  	return -ENOTTY;
>>  }
>> +
>> +#ifdef CONFIG_PCIE_KEYSTONE
>> +/*
>> + * The KeyStone PCIe controller has maximum read request size of 256 bytes.
>> + * Force this configuration for all EP including bridges.
>> + */
>> +static void quirk_limit_readrequest(struct pci_dev *dev) {
>> +	pcie_set_readrq(dev, 256);
>> +}
>> +DECLARE_PCI_FIXUP_FINAL(PCI_ANY_ID, PCI_ANY_ID,
>> +quirk_limit_readrequest); #endif /* CONFIG_TI_KEYSTONE_PCIE */
>
>You can't do this:
>
>A quirk for a specific hardware must not be enabled by compile-time options.
>You have to find a different way to do this.
>
>	Arnd
All,

Thanks for the comments. I will review them when I get a chance and respond.

Murali Karicheri
Linux Kernel, Software Development


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Andrew Murray - April 2, 2014, 4:47 p.m.
On 2 April 2014 16:43, Murali Karicheri <m-karicheri2@ti.com> wrote:

> Keystone pcie driver is developed based on other dw based pcie drivers
>
> such as pci-exynos that uses subsys_initcall(). I am new to this list,
>
> probably Jingoo (copied) has some history on why we can't use module.
> For now I will keep it as is and can be re-visited in the next revisions.
> Also I will experiment with PCIE port driver as well.
>
>
> BTW, PCIE driver currently uses Legacy or MSI IRQ. Keystone PCI has
> a platform IRQ. Is DT based irq configuration is the appropriate way
> to add this capability?

As far as I am aware - the PCI standards define a particular way for
devices to describe which interrupt will be used for things like
hotplug, AER and PME. These interrupts are always PCI interrupts (i.e.
MSI/MSI-X/legacy). Thus the port services code in the kernel uses
standard configuration space accesses to determine the interrupt to
use. Also note that it's not just the host bridge that can provide
these services but any PCIE device, I guess in this sense a host
bridge is treated like any other device.

If my understanding is correct I don't believe the current port
services code allows exceptions to this, i.e. to say this host bridge
actually uses a platform IRQ for AER rather than an MSI. Though this
may be quite useful as I suspect many host bridges provide interrupts
for things like PME through platform IRQs rather that PCI interrupts.

Does the Keystone have platform IRQs for things like AER? Is that
because the IP makes these events available through platform IRQs in
addition to the standard PCI means?

Andrew Murray
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Karicheri, Muralidharan - April 2, 2014, 5:17 p.m.
Arnd,

Thanks for reviewing the RFC patch. Please see below my response.

On 3/25/2014 3:44 AM, Arnd Bergmann wrote:
> On Monday 24 March 2014 20:35:26 Murali Karicheri wrote:
>> +
>> +int k2_pcie_platform_setup(struct platform_device *pdev)
>> +{
>> +	struct resource *phy_base_r, *devstat_r;
>> +	void __iomem *phy_base, *devstat;
>> +	u32 val;
>> +	int i;
>> +
>> +	devstat_r = platform_get_resource_byname(pdev, IORESOURCE_MEM,
>> +						 "reg_devcfg");
>> +	if (!devstat_r)
>> +		return -ENODEV;
> It seems you have a distinct register set for the PHY that you are
> driving here. Why not make this part generic PHY API driver?

Will investigate

>> +static int ks_pcie_establish_link(struct keystone_pcie *ks_pcie)
>> +{
>> +	struct pcie_port *pp = &ks_pcie->pp;
>> +	int count = 0;
>> +
>> +	dw_pcie_setup_rc(pp);
>> +
>> +	/* check if the link is up or not */
>> +	while (!dw_pcie_link_up(pp)) {
>> +		mdelay(100);
>> +		count++;
>> +		if (count == 10)
>> +			return -EINVAL;
>> +	}
>> +	return 0;
>> +}
> You are blocking the CPU for up to one second here, which is really
> nasty. Please find a way to move the code into a context where you
> can sleep and use msleep() instead, or better use an interrupt if the
> hardware supports that and use wait_for_completion().
Ok. I think I could use usleep_range() API here
>> +
>> +static void ks_pcie_msi_irq_handler(unsigned int irq, struct irq_desc *desc)
>> +{
>> +	struct keystone_pcie *ks_pcie = irq_desc_get_handler_data(desc);
>> +	u32 offset = irq - ks_pcie->msi_host_irqs[0], pending, vector;
>> +	struct pcie_port *pp = &ks_pcie->pp;
>> +	struct irq_chip *chip = irq_desc_get_chip(desc);
>> +	int src, virq;
> Did I understand this right that the MSI implementation can be used
> by any dw-pcie hardware of the same version? If so, it would be good
> to move it into an extra file so it can be shared with the next host
> driver that uses this version.
Yes. Can be moved to a separate file, dw-msi-v3.65.c ??

>> +/**
>> + * ks_pcie_set_outbound_trans() - Set PHYADDR <-> BUSADDR
>> + * mapping for outbound
>> + */
>> +static void ks_pcie_set_outbound_trans(struct keystone_pcie *ks_pcie)
>> +static void ks_pcie_set_inbound_trans(struct pcie_port *pp)
> Why do you need to set this up from the kernel? Please move the
> translation window setup into the boot loader if you can.

Why to create a u-boot dependency?
>> +static struct hw_pci keystone_pcie_hw = {
>> +	.nr_controllers	= 1,
>> +	.setup		= dw_pcie_setup,
>> +	.scan		= ks_pcie_scan_bus,
>> +	.swizzle        = pci_common_swizzle,
>> +	.add_bus	= dw_pcie_add_bus,
>> +	.map_irq	= ks_pcie_map_irq,
>> +};
> This can just be a local variable in the probe function.

Ok

>
>> +
>> +static int ks_pcie_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
>> +{
>> +	struct pcie_port *pp = sys_to_pcie(dev->bus->sysdata);
>> +	struct keystone_pcie *ks_pcie = to_keystone_pcie(pp);
>> +
>> +	dev_info(pp->dev, "ks_pcie_map_irq: pin %d\n", pin);
>> +
>> +	if (!pin || pin > ks_pcie->num_legacy_host_irqs) {
>> +		dev_err(pp->dev, "pci irq pin out of range\n");
>> +		return -1;
>> +	}
>> +
>> +	/* pin has values from 1-4 */
>> +	return (ks_pcie->virqs[pin - 1] >= 0) ?
>> +		ks_pcie->virqs[pin - 1] : -1;
>> +}
>> +
>> +
>> +static void ack_irq(struct irq_data *d)
>> +{
>> +}
>> +
>> +static void mask_irq(struct irq_data *d)
>> +{
>> +}
>> +
>> +static void unmask_irq(struct irq_data *d)
>> +{
>> +}
>> +
>> +static struct irq_chip ks_pcie_legacy_irq_chip = {
>> +	.name = "PCIe-LEGACY-IRQ",
>> +	.irq_ack = ack_irq,
>> +	.irq_mask = mask_irq,
>> +	.irq_unmask = unmask_irq,
>> +};
> Can you use the generic irqchip code here?

Will investigate.

>
>> +	/*
>> +	 * support upto MAX_LEGACY_HOST_IRQS host and legacy IRQs.
>> +	 * In dt from index 0 to 3
>> +	 */
>> +	for (i = 0; i < MAX_LEGACY_HOST_IRQS; i++) {
>> +		ks_pcie->legacy_host_irqs[i] = irq_of_parse_and_map(np, i);
>> +		if (ks_pcie->legacy_host_irqs[i] < 0)
>> +			break;
>> +		ks_pcie->num_legacy_host_irqs++;
>> +	}
>> +
>> +	if (ks_pcie->num_legacy_host_irqs) {
>> +		ks_pcie->legacy_irqd = irq_domain_add_linear(np,
>> +					ks_pcie->num_legacy_host_irqs,
>> +					&irq_domain_simple_ops, NULL);
>> +
>> +		if (!ks_pcie->legacy_irqd) {
>> +			dev_err(dev,
>> +				"Failed to add irq domain for legacy irqs\n");
>> +			return -EINVAL;
>> +		}
>> +	}
>> +
>> +	for (i = 0; i < ks_pcie->num_legacy_host_irqs; i++) {
>> +		ks_pcie->virqs[i] =
>> +			irq_create_mapping(ks_pcie->legacy_irqd, i);
>> +		irq_set_chip_and_handler(ks_pcie->virqs[i],
>> +			&ks_pcie_legacy_irq_chip, handle_level_irq);
>> +		irq_set_chip_data(ks_pcie->virqs[i], ks_pcie);
>> +		set_irq_flags(ks_pcie->virqs[i], IRQF_VALID);
>> +
>> +		if (ks_pcie->legacy_host_irqs[i] >= 0) {
>> +			irq_set_handler_data(ks_pcie->legacy_host_irqs[i],
>> +				ks_pcie);
>> +			irq_set_chained_handler(ks_pcie->legacy_host_irqs[i],
>> +				ks_pcie_legacy_irq_handler);
>> +		}
>> +		set_irq_flags(ks_pcie->legacy_host_irqs[i], IRQF_VALID);
>> +	}
> I have no idea how this would work with the standard interrupt-map property,
> since the legacy interrupt host is now the same device as the pci host.
>
> Maybe it's better to move the legacy irqchip handling entirely out of
> the driver and use a separate device node for the registers so it can
> come with its own #interrupt-cells, and then refer to this irqchip from
> the interrupt-map.

Will investigate

>> +	ks_pcie->clk = devm_clk_get(&pdev->dev, "pcie");
>> +	if (IS_ERR(ks_pcie->clk)) {
>> +		dev_err(&pdev->dev, "Failed to get pcie rc clock\n");
>> +		return PTR_ERR(ks_pcie->clk);
>> +	}
>> +	ret = clk_prepare_enable(ks_pcie->clk);
>> +	if (ret)
>> +		return ret;
> Could you move the clock handling into the generic dw-pcie code?

Could be. But currently only pci-exynos.c is using a clock name 
"pcie".pci-imx6.c uses pcie_axi" and
will have to be fixed so that we can move this code to the generic 
dw-pcie code.  Sean Cross is the
author for pci-imx6.c.

Sean,

Is "pcie_axi" is the pcie hw clock? If so, can you rename this to "pcie" 
so that  my patch can move the
clock handling code to pcie designware code?

>
>> +
>> +/* Keystone PCIe driver does not allow module unload */
>> +static int __init ks_pcie_init(void)
>> +{
>> +	return platform_driver_probe(&ks_pcie_driver, ks_pcie_probe);
>> +}
>> +subsys_initcall(ks_pcie_init);
> Why subsys_initcall?
>
> We should probably try to fix unloading soon.

Replied in another thread already from Andrew.

>
>> diff --git a/drivers/pci/host/pcie-ks-pdata.h b/drivers/pci/host/pcie-ks-pdata.h
>> new file mode 100644
>> index 0000000..a7626de
>> --- /dev/null
>> +++ b/drivers/pci/host/pcie-ks-pdata.h
>> @@ -0,0 +1,19 @@
>> +/*
>> + * Copyright (C) 2013-2014 Texas Instruments., Ltd.
>> + *		http://www.ti.com
>> + *
>> + * Author: Murali Karicheri <m-karicheri2@ti.com>
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License version 2 as
>> + * published by the Free Software Foundation.
>> + */
>> +
>> +/* platform specific setup for k2 pcie */
>> +int k2_pcie_platform_setup(struct platform_device *pdev);
>> +
>> +/* keystone pcie pdata configurations */
>> +struct keystone_pcie_pdata {
>> +	int (*setup)(struct platform_device *pdev);
>> +};
> This should all go away once you have a proper PHY driver.
Will investigate.
>
>> diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
>> index 3a02717..7c3f777 100644
>> --- a/drivers/pci/quirks.c
>> +++ b/drivers/pci/quirks.c
>> @@ -3461,3 +3461,15 @@ int pci_dev_specific_acs_enabled(struct pci_dev *dev, u16 acs_flags)
>>   
>>   	return -ENOTTY;
>>   }
>> +
>> +#ifdef CONFIG_PCIE_KEYSTONE
>> +/*
>> + * The KeyStone PCIe controller has maximum read request size of 256 bytes.
>> + * Force this configuration for all EP including bridges.
>> + */
>> +static void quirk_limit_readrequest(struct pci_dev *dev)
>> +{
>> +	pcie_set_readrq(dev, 256);
>> +}
>> +DECLARE_PCI_FIXUP_FINAL(PCI_ANY_ID, PCI_ANY_ID, quirk_limit_readrequest);
>> +#endif /* CONFIG_TI_KEYSTONE_PCIE */
> You can't do this:
>
> A quirk for a specific hardware must not be enabled by compile-time options.
> You have to find a different way to do this.

Will investigate.

>
> 	Arnd
>

Murali

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Karicheri, Muralidharan - April 2, 2014, 5:23 p.m.
On 4/2/2014 12:47 PM, Andrew Murray wrote:
> On 2 April 2014 16:43, Murali Karicheri <m-karicheri2@ti.com> wrote:
>
>> Keystone pcie driver is developed based on other dw based pcie drivers
>>
>> such as pci-exynos that uses subsys_initcall(). I am new to this list,
>>
>> probably Jingoo (copied) has some history on why we can't use module.
>> For now I will keep it as is and can be re-visited in the next revisions.
>> Also I will experiment with PCIE port driver as well.
>>
>>
>> BTW, PCIE driver currently uses Legacy or MSI IRQ. Keystone PCI has
>> a platform IRQ. Is DT based irq configuration is the appropriate way
>> to add this capability?
> As far as I am aware - the PCI standards define a particular way for
> devices to describe which interrupt will be used for things like
> hotplug, AER and PME. These interrupts are always PCI interrupts (i.e.
> MSI/MSI-X/legacy). Thus the port services code in the kernel uses
> standard configuration space accesses to determine the interrupt to
> use. Also note that it's not just the host bridge that can provide
> these services but any PCIE device, I guess in this sense a host
> bridge is treated like any other device.
>
> If my understanding is correct I don't believe the current port
> services code allows exceptions to this, i.e. to say this host bridge
> actually uses a platform IRQ for AER rather than an MSI. Though this
> may be quite useful as I suspect many host bridges provide interrupts
> for things like PME through platform IRQs rather that PCI interrupts.
>
> Does the Keystone have platform IRQs for things like AER? Is that
> because the IP makes these events available through platform IRQs in
> addition to the standard PCI means?
>
> Andrew Murray
Andrew,

Yes. Keystone PCIe hw is based on designware hw version v3.65 that 
implements
Error interrupt as a platform IRQ only (not in addition) and 
unfortunately standard
PCI means are not supported. The latter versions do support standard PCI 
means.

Murali

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Lucas Stach - April 3, 2014, 8:32 a.m.
Am Mittwoch, den 02.04.2014, 13:17 -0400 schrieb Murali Karicheri:
> Arnd,
> 
> Thanks for reviewing the RFC patch. Please see below my response.
> 
> On 3/25/2014 3:44 AM, Arnd Bergmann wrote:
> > On Monday 24 March 2014 20:35:26 Murali Karicheri wrote:
[...]
> 
> >> +	ks_pcie->clk = devm_clk_get(&pdev->dev, "pcie");
> >> +	if (IS_ERR(ks_pcie->clk)) {
> >> +		dev_err(&pdev->dev, "Failed to get pcie rc clock\n");
> >> +		return PTR_ERR(ks_pcie->clk);
> >> +	}
> >> +	ret = clk_prepare_enable(ks_pcie->clk);
> >> +	if (ret)
> >> +		return ret;
> > Could you move the clock handling into the generic dw-pcie code?
> 
> Could be. But currently only pci-exynos.c is using a clock name 
> "pcie".pci-imx6.c uses pcie_axi" and
> will have to be fixed so that we can move this code to the generic 
> dw-pcie code.  Sean Cross is the
> author for pci-imx6.c.
> 
> Sean,
> 
> Is "pcie_axi" is the pcie hw clock? If so, can you rename this to "pcie" 
> so that  my patch can move the
> clock handling code to pcie designware code?
> 
My series "i.MX6 PCIe binding change and MSI support" already changes
the clock name. So we could consolidate the clock handling once this is
in. Only difference is that the i.MX6 needs an additional PHY clock.

Regards,
Lucas
Karicheri, Muralidharan - April 4, 2014, 4:15 p.m.
On 4/3/2014 4:32 AM, Lucas Stach wrote:
> Am Mittwoch, den 02.04.2014, 13:17 -0400 schrieb Murali Karicheri:
>> Arnd,
>>
>> Thanks for reviewing the RFC patch. Please see below my response.
>>
>> On 3/25/2014 3:44 AM, Arnd Bergmann wrote:
>>> On Monday 24 March 2014 20:35:26 Murali Karicheri wrote:
> [...]
>>>> +	ks_pcie->clk = devm_clk_get(&pdev->dev, "pcie");
>>>> +	if (IS_ERR(ks_pcie->clk)) {
>>>> +		dev_err(&pdev->dev, "Failed to get pcie rc clock\n");
>>>> +		return PTR_ERR(ks_pcie->clk);
>>>> +	}
>>>> +	ret = clk_prepare_enable(ks_pcie->clk);
>>>> +	if (ret)
>>>> +		return ret;
>>> Could you move the clock handling into the generic dw-pcie code?
>> Could be. But currently only pci-exynos.c is using a clock name
>> "pcie".pci-imx6.c uses pcie_axi" and
>> will have to be fixed so that we can move this code to the generic
>> dw-pcie code.  Sean Cross is the
>> author for pci-imx6.c.
>>
>> Sean,
>>
>> Is "pcie_axi" is the pcie hw clock? If so, can you rename this to "pcie"
>> so that  my patch can move the
>> clock handling code to pcie designware code?
>>
> My series "i.MX6 PCIe binding change and MSI support" already changes
> the clock name. So we could consolidate the clock handling once this is
> in. Only difference is that the i.MX6 needs an additional PHY clock.
>
> Regards,
> Lucas
Lucas,

Thanks. I will send a patch for this.

Murali
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Karicheri, Muralidharan - April 7, 2014, 4:38 p.m.
On 3/25/2014 12:54 PM, Jason Gunthorpe wrote:
> On Tue, Mar 25, 2014 at 08:44:36AM +0100, Arnd Bergmann wrote:
>
>> I have no idea how this would work with the standard interrupt-map property,
>> since the legacy interrupt host is now the same device as the pci host.
>>
>> Maybe it's better to move the legacy irqchip handling entirely out of
>> the driver and use a separate device node for the registers so it can
>> come with its own #interrupt-cells, and then refer to this irqchip from
>> the interrupt-map.
> The other DW PCI-E drivers are being fixed to use interrupt-map, so I
> think this driver should be fixed before it goes in as well.
Jason,

Could you send me a patch reference or branch that I can review to 
better understand
changes required in my driver to use the bindings you have described below?

Murali
> Other PCI-E hosts have handled this particular problem with a
> construction like this:
>
>         pcie@21800000 {
>                 compatible = "ti,keystone2-pcie";
>                 device_type = "pci";
>                 #address-cells = <3>;
>                 #size-cells = <2>;
>                 #interrupt-cells = <1>;
> 	       reg = ..
>
>                 pcie_intc: interrupt-controller {
>                    interrupt-controller;
> 		  #address-cells = <0>;
>                    #interrupt-cells = <1>;
>                 }
>
>                 interrupts =  ... enough to decode INTx;
>
> 	       interrtup-map = <0 0 0 1 &pcie_intc 1>, // INT A
> 	                       <0 0 0 2 &pcie_intc 2>, // INT B
>                                 <0 0 0 3 &pcie_intc 3>, // INT C
>                                 <0 0 0 4 &pcie_intc 4>; // INT D
>         }
>
> When the legacy irq domain is created it should be bound to the
> pcie_intc node, not to pcie node.
>
> ks_pcie_map_irq should be removed.
The latest dw core driver still had map_irq() being provided by the driver.
So any patch reference will help me understand that you describe here.

Thanks

Murali
>
>>> +#ifdef CONFIG_PCIE_KEYSTONE
>>> +/*
>>> + * The KeyStone PCIe controller has maximum read request size of 256 bytes.
>>> + * Force this configuration for all EP including bridges.
>>> + */
>>> +static void quirk_limit_readrequest(struct pci_dev *dev)
>>> +{
>>> +	pcie_set_readrq(dev, 256);
>>> +}
>>> +DECLARE_PCI_FIXUP_FINAL(PCI_ANY_ID, PCI_ANY_ID, quirk_limit_readrequest);
>>> +#endif /* CONFIG_TI_KEYSTONE_PCIE */
>> You can't do this:
>>
>> A quirk for a specific hardware must not be enabled by compile-time options.
>> You have to find a different way to do this.
> This configuration should happen automatically by the PCI core if the
> config spaces are correct. See pcie_write_mrrs, pcie_write_mps,
> pcie_bus_configure_settings, etc.
>
> Your host will need to conform to the PCI spec and provide a root
> port bridge header for this to work.
>
> Also, even in the keystone case the MRRS should not be globally forced
> like this, there may be other bridges in the system with a 128 byte
> MPS.
>
> Jason

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Jason Gunthorpe - April 7, 2014, 4:46 p.m.
On Mon, Apr 07, 2014 at 12:38:23PM -0400, Murali Karicheri wrote:
> On 3/25/2014 12:54 PM, Jason Gunthorpe wrote:
> >On Tue, Mar 25, 2014 at 08:44:36AM +0100, Arnd Bergmann wrote:
> >
> >>I have no idea how this would work with the standard interrupt-map property,
> >>since the legacy interrupt host is now the same device as the pci host.
> >>
> >>Maybe it's better to move the legacy irqchip handling entirely out of
> >>the driver and use a separate device node for the registers so it can
> >>come with its own #interrupt-cells, and then refer to this irqchip from
> >>the interrupt-map.
> >The other DW PCI-E drivers are being fixed to use interrupt-map, so I
> >think this driver should be fixed before it goes in as well.
> 
> Could you send me a patch reference or branch that I can review to
> better understand changes required in my driver to use the bindings
> you have described below?

Bjorn is now merging it:

[PATCH v2 0/6] PCI irq mapping fixes and cleanups
http://www.spinics.net/lists/linux-pci/msg29589.html

Jason
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Patch

diff --git a/Documentation/devicetree/bindings/pci/pcie-keystone.txt b/Documentation/devicetree/bindings/pci/pcie-keystone.txt
new file mode 100644
index 0000000..b7b7651
--- /dev/null
+++ b/Documentation/devicetree/bindings/pci/pcie-keystone.txt
@@ -0,0 +1,32 @@ 
+Keystone PCIE Root complex device tree bindings
+-----------------------------------------------
+
+Sample bindings shown below:-
+
+ - Remove enable-linktrain if boot loader already does Link training and do EP
+   configuration.
+ - To Disable SERDES initialization during Linux boot up, remove the "reg_serdes"
+   reg values from the reg property.
+
+	pcie@21800000 {
+		compatible = "ti,keystone2-pcie";
+		device_type = "pci";
+		clocks = <&clkpcie>;
+		clock-names = "pcie";
+		#address-cells = <3>;
+		#size-cells = <2>;
+		#interrupt-cells = <1>;
+		reg =  <0x21800000 0x1000>, <0x0262014c 4>, <0x02320000 0x4000>;
+		reg-names = "reg_rc_app", "reg_devcfg", "reg_serdes";
+		interrupts =	<0 26 0xf01>, <0 27 0xf01>, <0 28 0xf01>, <0 29 0xf01>,
+				<0 30 0xf01>, <0 31 0xf01>, <0 32 0xf01>, <0 33 0xf01>,
+				<0 34 0xf01>, <0 35 0xf01>, <0 36 0xf01>, <0 37 0xf01>,
+				<0 38 0xf01>; /* Error IRQ */
+
+		ranges = <0x00000800 0 0x21801000 0x21801000 0 0x0002000   /* Configuration space */
+			  0x81000000 0 0	  0x24000000 0 0x4000	   /* downstream I/O */
+			  0x82000000 0 0x50000000 0x50000000 0 0x10000000>; /* non-prefetchable memory */
+
+		num-lanes = <2>;
+		ti,enable-linktrain;
+	};
diff --git a/drivers/pci/host/Kconfig b/drivers/pci/host/Kconfig
index 47d46c6..9e45260 100644
--- a/drivers/pci/host/Kconfig
+++ b/drivers/pci/host/Kconfig
@@ -33,4 +33,9 @@  config PCI_RCAR_GEN2
 	  There are 3 internal PCI controllers available with a single
 	  built-in EHCI/OHCI host controller present on each one.
 
+config PCIE_KEYSTONE
+	bool "TI Keystone PCIe controller"
+	depends on ARCH_KEYSTONE
+	select PCIE_DW
+	select PCIEPORTBUS
 endmenu
diff --git a/drivers/pci/host/Makefile b/drivers/pci/host/Makefile
index 13fb333..34e28c9 100644
--- a/drivers/pci/host/Makefile
+++ b/drivers/pci/host/Makefile
@@ -4,3 +4,4 @@  obj-$(CONFIG_PCI_IMX6) += pci-imx6.o
 obj-$(CONFIG_PCI_MVEBU) += pci-mvebu.o
 obj-$(CONFIG_PCI_TEGRA) += pci-tegra.o
 obj-$(CONFIG_PCI_RCAR_GEN2) += pci-rcar-gen2.o
+obj-$(CONFIG_PCIE_KEYSTONE) += pcie-keystone.o k2-platform.o
diff --git a/drivers/pci/host/k2-platform.c b/drivers/pci/host/k2-platform.c
new file mode 100644
index 0000000..e10db00
--- /dev/null
+++ b/drivers/pci/host/k2-platform.c
@@ -0,0 +1,191 @@ 
+/*
+ * PCIe Keystone platform specific driver code
+ *
+ * Copyright (C) 2013-2014 Texas Instruments, Inc.
+ *		http://www.ti.com
+ *
+ * Author: Murali Karicheri <m-karicheri2@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <asm/setup.h>
+
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+
+#include "pcie-ks-pdata.h"
+
+#define reg_dump(addr, mask) \
+		pr_debug("reg %p has value %x\n", (void *)addr, \
+				(__raw_readl(addr) & ~mask))
+
+#define PCIE_RC_MODE		(BIT(2))
+#define PCIE_MODE_MASK		(BIT(1) | BIT(2))
+
+static inline void reg_rmw(void __iomem *addr, u32 mask, u32 val)
+{
+	u32 read_data, data;
+	read_data = readl(addr);
+	data = (val & ~mask) | (read_data & mask);
+	writel(data, addr);
+}
+
+struct serdes_config {
+	u32 reg;
+	u32 mask;
+	u32 val;
+};
+
+/* SERDES configuration */
+static struct serdes_config k2_pcie_serdes_cfg[] = {
+	{ 0x000, 0xffff00ff, 0x00000800 },
+	{ 0x060, 0xff000000, 0x00041c5c },
+	{ 0x064, 0x000000ff, 0x0343c700 },
+	{ 0x06c, 0xffffff00, 0x00000012 },
+	{ 0x068, 0xff00ffff, 0x00070000 },
+	{ 0x078, 0xffff00ff, 0x0000c000 },
+	{ 0x200, 0xffffff00, 0x00000000 },
+	{ 0x204, 0x00ffff00, 0x5e000080 },
+	{ 0x208, 0xffffff00, 0x00000006 },
+	{ 0x210, 0xffffff00, 0x00000023 },
+	{ 0x214, 0x00ff0000, 0x2e003060 },
+	{ 0x218, 0x00ffffff, 0x76000000 },
+	{ 0x22c, 0xff00ff00, 0x00100002 },
+	{ 0x2a0, 0x0000ffff, 0xffee0000 },
+	{ 0x2a4, 0xffffff00, 0x0000000f },
+	{ 0x204, 0x00ffffff, 0x5e000000 },
+	{ 0x208, 0xffffff00, 0x00000006 },
+	{ 0x278, 0xffff00ff, 0x00002000 },
+	{ 0x280, 0xff00ff00, 0x00280028 },
+	{ 0x284, 0x00000000, 0x2d0f0385 },
+	{ 0x250, 0x00ffffff, 0xd0000000 },
+	{ 0x284, 0xffffff00, 0x00000085 },
+	{ 0x294, 0x00ffffff, 0x20000000 },
+
+	{ 0x400, 0xffffff00, 0x00000000 },
+	{ 0x404, 0x00ffff00, 0x5e000080 },
+	{ 0x408, 0xffffff00, 0x00000006 },
+	{ 0x410, 0xffffff00, 0x00000023 },
+	{ 0x414, 0x00ff0000, 0x2e003060 },
+	{ 0x418, 0x00ffffff, 0x76000000 },
+	{ 0x42c, 0xff00ff00, 0x00100002 },
+	{ 0x4a0, 0x0000ffff, 0xffee0000 },
+	{ 0x4a4, 0xffffff00, 0x0000000f },
+	{ 0x404, 0x00ffffff, 0x5e000000 },
+	{ 0x408, 0xffffff00, 0x00000006 },
+	{ 0x478, 0xffff00ff, 0x00002000 },
+	{ 0x480, 0xff00ff00, 0x00280028 },
+	{ 0x484, 0x00000000, 0x2d0f0385 },
+	{ 0x450, 0x00ffffff, 0xd0000000 },
+	{ 0x494, 0x00ffffff, 0x20000000 },
+
+	{ 0x604, 0xffffff00, 0x00000080 },
+	{ 0x600, 0xffffff00, 0x00000000 },
+	{ 0x604, 0x00ffffff, 0x5e000000 },
+	{ 0x608, 0xffffff00, 0x00000006 },
+	{ 0x610, 0xffffff00, 0x00000023 },
+	{ 0x614, 0x00ff0000, 0x2e003060 },
+	{ 0x618, 0x00ffffff, 0x76000000 },
+	{ 0x62c, 0xff00ff00, 0x00100002 },
+	{ 0x6a0, 0x0000ffff, 0xffee0000 },
+	{ 0x6a4, 0xffffff00, 0x0000000f },
+	{ 0x604, 0x00ffffff, 0x5e000000 },
+	{ 0x608, 0xffffff00, 0x00000006 },
+	{ 0x678, 0xffff00ff, 0x00002000 },
+	{ 0x680, 0xff00ff00, 0x00280028 },
+	{ 0x684, 0x00000000, 0x2d0f0385 },
+	{ 0x650, 0x00ffffff, 0xd0000000 },
+	{ 0x694, 0x00ffffff, 0x20000000 },
+
+	{ 0x800, 0xffffff00, 0x00000000 },
+	{ 0x804, 0x00ffff00, 0x5e000080 },
+	{ 0x808, 0xffffff00, 0x00000006 },
+	{ 0x810, 0xffffff00, 0x00000023 },
+	{ 0x814, 0x00ff0000, 0x2e003060 },
+	{ 0x818, 0x00ffffff, 0x76000000 },
+	{ 0x82c, 0xff00ff00, 0x00100002 },
+	{ 0x8a0, 0x0000ffff, 0xffee0000 },
+	{ 0x8a4, 0xffffff00, 0x0000000f },
+	{ 0x804, 0x00ffffff, 0x5e000000 },
+	{ 0x808, 0xffffff00, 0x00000006 },
+	{ 0x878, 0xffff00ff, 0x00002000 },
+	{ 0x880, 0xff00ff00, 0x00280028 },
+	{ 0x884, 0x00000000, 0x2d0f0385 },
+	{ 0x850, 0x00ffffff, 0xd0000000 },
+	{ 0x894, 0x00ffffff, 0x20000000 },
+
+	{ 0xa00, 0xffff00ff, 0x00000100 },
+	{ 0xa08, 0xff000000, 0x00e12c08 },
+	{ 0xa0c, 0xffffff00, 0x00000081 },
+	{ 0xa18, 0xff00ffff, 0x00e80000 },
+	{ 0xa30, 0x00ffff00, 0x002f2f00 },
+	{ 0xa48, 0xff0000ff, 0x00e3ce00 },
+	{ 0xa4c, 0x0000ffff, 0xac820000 },
+	{ 0xa54, 0x00ffffff, 0xc0000000 },
+	{ 0xa58, 0xffff0000, 0x00001441 },
+	{ 0xa84, 0xffff0000, 0x00000301 },
+
+	{ 0xa8c, 0x0000ffff, 0x81030000 },
+	{ 0xa90, 0xffff0000, 0x00006001 },
+	{ 0xa94, 0x00ffffff, 0x01000000 },
+	{ 0xaa0, 0x00ffffff, 0x81000000 },
+	{ 0xabc, 0x00ffffff, 0xff000000 },
+	{ 0xac0, 0xffffff00, 0x0000008b },
+
+	{ 0x000, 0xffffff00, 0x00000003 },
+	{ 0xa00, 0xffffff00, 0x0000009f },
+};
+
+int k2_pcie_platform_setup(struct platform_device *pdev)
+{
+	struct resource *phy_base_r, *devstat_r;
+	void __iomem *phy_base, *devstat;
+	u32 val;
+	int i;
+
+	devstat_r = platform_get_resource_byname(pdev, IORESOURCE_MEM,
+						 "reg_devcfg");
+	if (!devstat_r)
+		return -ENODEV;
+
+	devstat = devm_ioremap_resource(&pdev->dev, devstat_r);
+	if (IS_ERR(devstat)) {
+		dev_warn(&pdev->dev, "pcie devstat bindings missing\n");
+		return PTR_ERR(devstat);
+	}
+
+	phy_base_r = platform_get_resource_byname(pdev, IORESOURCE_MEM,
+						 "reg_serdes");
+	if (phy_base_r) {
+		phy_base = devm_ioremap_resource(&pdev->dev, phy_base_r);
+		if (IS_ERR(phy_base))
+			dev_info(&pdev->dev,
+				"phy (serdes) initialized by boot loader\n");
+		if (phy_base) {
+			for (i = 0; i < ARRAY_SIZE(k2_pcie_serdes_cfg); i++) {
+				reg_rmw((phy_base + k2_pcie_serdes_cfg[i].reg),
+					k2_pcie_serdes_cfg[i].mask,
+					k2_pcie_serdes_cfg[i].val);
+				reg_dump((phy_base + k2_pcie_serdes_cfg[i].reg),
+					k2_pcie_serdes_cfg[i].mask);
+			}
+		}
+	}
+
+	udelay(2000);
+
+	/* enable RC mode in devcfg */
+	val = readl(devstat);
+	val &= ~PCIE_MODE_MASK;
+	val |= PCIE_RC_MODE;
+	writel(val, devstat);
+	return 0;
+}
diff --git a/drivers/pci/host/pcie-keystone.c b/drivers/pci/host/pcie-keystone.c
new file mode 100644
index 0000000..aed203f
--- /dev/null
+++ b/drivers/pci/host/pcie-keystone.c
@@ -0,0 +1,860 @@ 
+/*
+ * PCIe host controller driver for Texas Instruments Keystone SoCs
+ *
+ * Copyright (C) 2013-2014 Texas Instruments., Ltd.
+ *		http://www.ti.com
+ *
+ * Author: Murali Karicheri <m-karicheri2@ti.com>
+ * Implementation based on pci-exynos.c and pcie-designware.c
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/of_irq.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/msi.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/resource.h>
+#include <linux/signal.h>
+#include <linux/types.h>
+
+#include "pcie-designware.h"
+#include "pcie-ks-pdata.h"
+
+#define DRIVER_NAME	"keystone-pcie"
+/*
+ *  Application Register Offsets
+ */
+#define CMD_STATUS			0x004
+#define CFG_SETUP			0x008
+#define IOBASE				0x00c
+#define OB_SIZE				0x030
+#define IRQ_EOI                         0x050
+#define MSI_IRQ				0x054
+#define MSI0_IRQ_STATUS			0x104
+#define MSI0_IRQ_ENABLE_SET		0x108
+#define MSI0_IRQ_ENABLE_CLR		0x10c
+#define IRQ_STATUS			0x184
+#define IRQ_ENABLE_SET			0x188
+#define IRQ_ENABLE_CLR			0x18c
+#define IB_BAR0				0x300
+#define IB_START0_LO			0x304
+#define IB_START0_HI			0x308
+#define IB_OFFSET0			0x30c
+/* 32 Registers */
+#define OB_OFFSET_INDEX(n)		(0x200 + (8 * n))
+/* 32 Registers */
+#define OB_OFFSET_HI(n)			(0x204 + (8 * n))
+
+/*
+ * PCIe Config Register Offsets
+ */
+#define DEBUG0			        0x728
+#define PL_GEN2			        0x80c
+
+/* Application command register values */
+#define DBI_CS2_EN_VAL		        BIT(5)
+#define IB_XLAT_EN_VAL		        BIT(2)
+#define OB_XLAT_EN_VAL		        BIT(1)
+#define LTSSM_EN_VAL		        BIT(0)
+
+/* Link training encodings as indicated in DEBUG0 register */
+#define LTSSM_STATE_MASK	        0x1f
+#define LTSSM_STATE_L0		        0x11
+
+/* Directed Speed Change */
+#define DIR_SPD				(1 << 17)
+
+/* Outbound window size specified as power of 2 MB */
+#define CFG_PCIM_WIN_SZ_IDX	        3
+#define CFG_PCIM_WIN_CNT	        32
+
+/* offset relative to SPACE0_LOCAL_CFG_OFFSET */
+#define SPACE0_REMOTE_CFG_OFFSET	0x1000
+
+/* driver specific constants */
+#define MAX_MSI_HOST_IRQS		8
+#define MSI_IRQ_OFFSET			4
+#define MAX_LEGACY_HOST_IRQS		4
+
+static struct keystone_pcie_pdata keystone2_data = {
+	.setup = k2_pcie_platform_setup,
+};
+
+struct keystone_pcie {
+	const struct keystone_pcie_pdata *pdata;
+	struct	clk		*clk;
+	struct	resource	reg_app;
+	void	__iomem		*va_reg_app;
+	int			en_link_train;
+	struct	pcie_port	pp;
+
+	int			num_legacy_host_irqs;
+	int			legacy_host_irqs[MAX_LEGACY_HOST_IRQS];
+	int			virqs[MAX_LEGACY_HOST_IRQS];
+	struct	irq_domain	*legacy_irqd;
+
+	int			num_msi_host_irqs;
+	int			msi_host_irqs[MAX_MSI_HOST_IRQS];
+};
+
+#define to_keystone_pcie(x)	container_of(x, struct keystone_pcie, pp)
+
+static inline struct pcie_port *sys_to_pcie(struct pci_sys_data *sys)
+{
+	return sys->private_data;
+}
+
+static int ks_pcie_establish_link(struct keystone_pcie *ks_pcie)
+{
+	struct pcie_port *pp = &ks_pcie->pp;
+	int count = 0;
+
+	dw_pcie_setup_rc(pp);
+
+	/* check if the link is up or not */
+	while (!dw_pcie_link_up(pp)) {
+		mdelay(100);
+		count++;
+		if (count == 10)
+			return -EINVAL;
+	}
+	return 0;
+}
+
+static void ks_mask_legacy_irq(void __iomem *reg_virt, int i)
+{
+	writel(0x1, reg_virt + IRQ_ENABLE_CLR + (i << 4));
+}
+
+static void ks_unmask_legacy_irq(void __iomem *reg_virt, int i)
+{
+	writel(0x1, reg_virt + IRQ_ENABLE_SET + (i << 4));
+}
+
+static void ks_pcie_msi_irq_handler(unsigned int irq, struct irq_desc *desc)
+{
+	struct keystone_pcie *ks_pcie = irq_desc_get_handler_data(desc);
+	u32 offset = irq - ks_pcie->msi_host_irqs[0], pending, vector;
+	struct pcie_port *pp = &ks_pcie->pp;
+	struct irq_chip *chip = irq_desc_get_chip(desc);
+	int src, virq;
+
+	dev_dbg(pp->dev, "ks_pcie_msi_irq_handler, irq %d\n", irq);
+
+	/*
+	 * The chained irq handler installation would have replaced normal
+	 * interrupt driver handler so we need to take care of mask/unmask and
+	 * ack operation.
+	 */
+	chip->irq_mask(&desc->irq_data);
+	if (chip->irq_ack)
+		chip->irq_ack(&desc->irq_data);
+
+	pending = readl(ks_pcie->va_reg_app + MSI0_IRQ_STATUS + (offset << 4));
+	/*
+	 * MSI0, Status bit 0-3 shows vectors 0, 8, 16, 24, MSI1 status bit
+	 * shows 1, 9, 17, 25 and so forth
+	 */
+	for (src = 0; src < 4; src++) {
+		if (BIT(src) & pending) {
+			vector = offset + (src << 3);
+			virq = irq_linear_revmap(pp->irq_domain, vector);
+			dev_dbg(pp->dev,
+				"irq: bit %d, vector %d, virq %d\n",
+				 src, vector, virq);
+			generic_handle_irq(virq);
+		}
+	}
+
+	if (chip->irq_eoi)
+		chip->irq_eoi(&desc->irq_data);
+	chip->irq_unmask(&desc->irq_data);
+}
+
+static void ks_pcie_ack_msi(struct irq_data *d)
+{
+	u32 offset, reg_offset, bit_pos;
+	struct keystone_pcie *ks_pcie;
+	unsigned int irq = d->irq;
+	struct msi_desc *msi;
+	struct irq_desc *desc;
+	struct pcie_port *pp;
+
+	desc = irq_to_desc(irq);
+	msi = irq_desc_get_msi_desc(desc);
+	pp = sys_to_pcie(msi->dev->bus->sysdata);
+	ks_pcie = to_keystone_pcie(pp);
+
+	offset = irq - irq_linear_revmap(pp->irq_domain, 0);
+
+	reg_offset = offset % 8;
+	bit_pos = offset >> 3;
+
+	writel(BIT(bit_pos),
+		ks_pcie->va_reg_app + MSI0_IRQ_STATUS + (reg_offset << 4));
+	writel(reg_offset + MSI_IRQ_OFFSET, ks_pcie->va_reg_app + IRQ_EOI);
+}
+
+static void ks_pcie_mask_msi(struct irq_data *d)
+{
+	u32 offset, reg_offset, bit_pos;
+	struct keystone_pcie *ks_pcie;
+	unsigned int irq = d->irq;
+	struct msi_desc *msi;
+	struct pcie_port *pp;
+	struct irq_desc *desc;
+
+
+	desc = irq_to_desc(irq);
+	msi = irq_desc_get_msi_desc(desc);
+	pp = sys_to_pcie(msi->dev->bus->sysdata);
+	ks_pcie = to_keystone_pcie(pp);
+
+	offset = irq - irq_linear_revmap(pp->irq_domain, 0);
+
+	reg_offset = offset % 8;
+	bit_pos = offset >> 3;
+
+	/* mask the end point if PVM implemented */
+	if (IS_ENABLED(CONFIG_PCI_MSI)) {
+		if (msi->msi_attrib.maskbit)
+			mask_msi_irq(d);
+	}
+
+	writel(BIT(bit_pos),
+		ks_pcie->va_reg_app + MSI0_IRQ_ENABLE_CLR + (reg_offset << 4));
+}
+
+static void ks_pcie_unmask_msi(struct irq_data *d)
+{
+	u32 offset, reg_offset, bit_pos;
+	struct keystone_pcie *ks_pcie;
+	unsigned int irq = d->irq;
+	struct msi_desc *msi;
+	struct irq_desc *desc;
+	struct pcie_port *pp;
+
+	desc = irq_to_desc(irq);
+	msi = irq_desc_get_msi_desc(desc);
+	pp = sys_to_pcie(msi->dev->bus->sysdata);
+	ks_pcie = to_keystone_pcie(pp);
+
+	offset = irq - irq_linear_revmap(pp->irq_domain, 0);
+
+	reg_offset = offset % 8;
+	bit_pos = offset >> 3;
+
+	/* mask the end point if PVM implemented */
+	if (IS_ENABLED(CONFIG_PCI_MSI)) {
+		if (msi->msi_attrib.maskbit)
+			unmask_msi_irq(d);
+	}
+
+	writel(BIT(bit_pos),
+		ks_pcie->va_reg_app + MSI0_IRQ_ENABLE_SET + (reg_offset << 4));
+}
+
+static struct irq_chip ks_pcie_msi_chip = {
+	.name = "PCIe-MSI",
+	.irq_ack = ks_pcie_ack_msi,
+	.irq_mask = ks_pcie_mask_msi,
+	.irq_unmask = ks_pcie_unmask_msi,
+};
+
+static int ks_pcie_msi_map(struct irq_domain *domain, unsigned int irq,
+			irq_hw_number_t hwirq)
+{
+	irq_set_chip_and_handler(irq, &ks_pcie_msi_chip, handle_level_irq);
+	irq_set_chip_data(irq, domain->host_data);
+	set_irq_flags(irq, IRQF_VALID);
+
+	return 0;
+}
+
+static const struct irq_domain_ops msi_domain_ops = {
+	.map = ks_pcie_msi_map,
+};
+
+/**
+ * ks_pcie_legacy_irq_handler() - Handle legacy interrupt
+ * @irq: IRQ line for legacy interrupts
+ * @desc: Pointer to irq descriptor
+ *
+ * Traverse through pending legacy interrupts and invoke handler for each. Also
+ * takes care of interrupt controller level mask/ack operation.
+ */
+static void ks_pcie_legacy_irq_handler(unsigned int irq, struct irq_desc *desc)
+{
+	struct keystone_pcie *ks_pcie = irq_desc_get_handler_data(desc);
+	u32 irq_offset = irq - ks_pcie->legacy_host_irqs[0], pending;
+	struct irq_chip *chip = irq_desc_get_chip(desc);
+	int virq;
+
+	dev_dbg(ks_pcie->pp.dev, ": Handling legacy irq %d\n", irq);
+
+	/*
+	 * The chained irq handler installation would have replaced normal
+	 * interrupt driver handler so we need to take care of mask/unmask and
+	 * ack operation.
+	 */
+	chip->irq_mask(&desc->irq_data);
+	if (chip->irq_ack)
+		chip->irq_ack(&desc->irq_data);
+
+	pending = readl(ks_pcie->va_reg_app + IRQ_STATUS + (irq_offset << 4));
+
+	if (BIT(0) & pending) {
+		virq = irq_linear_revmap(ks_pcie->legacy_irqd, irq_offset);
+		dev_dbg(ks_pcie->pp.dev,
+			": irq: irq_offset %d, virq %d\n", irq_offset, virq);
+		generic_handle_irq(virq);
+	}
+
+	/* EOI the INTx interrupt */
+	writel(irq_offset, ks_pcie->va_reg_app + IRQ_EOI);
+
+	if (chip->irq_eoi)
+		chip->irq_eoi(&desc->irq_data);
+	chip->irq_unmask(&desc->irq_data);
+}
+
+static void ks_pcie_enable_interrupts(struct keystone_pcie *ks_pcie)
+{
+	int i;
+
+	if (ks_pcie->num_legacy_host_irqs) {
+		for (i = 0; i < ks_pcie->num_legacy_host_irqs; i++) {
+			if (ks_pcie->legacy_host_irqs[i] >= 0)
+				ks_unmask_legacy_irq(ks_pcie->va_reg_app, i);
+			else
+				ks_mask_legacy_irq(ks_pcie->va_reg_app, i);
+		}
+	}
+
+	if (IS_ENABLED(CONFIG_PCI_MSI)) {
+		for (i = 0; i < ks_pcie->num_msi_host_irqs; i++) {
+			irq_set_chained_handler(ks_pcie->msi_host_irqs[i],
+				ks_pcie_msi_irq_handler);
+			irq_set_handler_data(ks_pcie->msi_host_irqs[i],
+						ks_pcie);
+
+		}
+	}
+	return;
+}
+
+/**
+ * ks_pcie_set_outbound_trans() - Set PHYADDR <-> BUSADDR
+ * mapping for outbound
+ */
+static void ks_pcie_set_outbound_trans(struct keystone_pcie *ks_pcie)
+{
+	u32 start = ks_pcie->pp.mem.start, end = ks_pcie->pp.mem.end;
+	int i, tr_size;
+
+	dev_dbg(ks_pcie->pp.dev,
+		"Setting outbound translation for %#x-%#x\n",
+		 start, end);
+
+	/* Set outbound translation size per window division */
+	writel(CFG_PCIM_WIN_SZ_IDX & 0x7, ks_pcie->va_reg_app + OB_SIZE);
+
+	tr_size = (1 << (CFG_PCIM_WIN_SZ_IDX & 0x7)) * SZ_1M;
+
+	/* Using Direct 1:1 mapping of RC <-> PCI memory space */
+	for (i = 0; (i < CFG_PCIM_WIN_CNT) && (start < end); i++) {
+		writel(start | 1, ks_pcie->va_reg_app + OB_OFFSET_INDEX(i));
+		writel(0, ks_pcie->va_reg_app + OB_OFFSET_HI(i));
+		start += tr_size;
+	}
+
+	/* Enable OB translation */
+	writel(OB_XLAT_EN_VAL | readl(ks_pcie->va_reg_app + CMD_STATUS),
+		ks_pcie->va_reg_app + CMD_STATUS);
+}
+
+/**
+ * ks_pcie_set_dbi_mode() - Set DBI mode to access overlaid BAR mask registers
+ *
+ * Since modification of dbi_cs2 involves different clock domain, read the
+ * status back to ensure the transition is complete.
+ */
+static inline void ks_pcie_set_dbi_mode(void __iomem *reg_virt)
+{
+	u32 val;
+
+	writel(DBI_CS2_EN_VAL | readl(reg_virt + CMD_STATUS),
+		     reg_virt + CMD_STATUS);
+
+	do {
+		val = readl(reg_virt + CMD_STATUS);
+	} while (!(val & DBI_CS2_EN_VAL));
+}
+
+/**
+ * ks_pcie_clear_dbi_mode() - Disable DBI mode
+ *
+ * Since modification of dbi_cs2 involves different clock domain, read the
+ * status back to ensure the transition is complete.
+ */
+static inline void ks_pcie_clear_dbi_mode(void __iomem *reg_virt)
+{
+	u32 val;
+
+	writel(~DBI_CS2_EN_VAL & readl(reg_virt + CMD_STATUS),
+		     reg_virt + CMD_STATUS);
+
+	do {
+		val = readl(reg_virt + CMD_STATUS);
+	} while (val & DBI_CS2_EN_VAL);
+}
+
+static void ks_pcie_disable_bars(struct keystone_pcie *ks_pcie)
+{
+	struct pcie_port *pp = &ks_pcie->pp;
+
+	ks_pcie_set_dbi_mode(ks_pcie->va_reg_app);
+	writel(0, pp->dbi_base + PCI_BASE_ADDRESS_0);
+	writel(0, pp->dbi_base + PCI_BASE_ADDRESS_1);
+	ks_pcie_clear_dbi_mode(ks_pcie->va_reg_app);
+}
+
+static int
+keystone_pcie_fault(unsigned long addr, unsigned int fsr,
+		struct pt_regs *regs)
+{
+	unsigned long instr = *(unsigned long *) instruction_pointer(regs);
+
+	if ((instr & 0x0e100090) == 0x00100090) {
+		int reg = (instr >> 12) & 15;
+
+		regs->uregs[reg] = -1;
+		regs->ARM_pc += 4;
+	}
+	return 0;
+}
+
+static void __init ks_pcie_host_init(struct pcie_port *pp)
+{
+	struct keystone_pcie *ks_pcie = to_keystone_pcie(pp);
+
+	ks_pcie_establish_link(ks_pcie);
+	ks_pcie_disable_bars(ks_pcie);
+	ks_pcie_set_outbound_trans(ks_pcie);
+	ks_pcie_enable_interrupts(ks_pcie);
+
+	/* Enable 32-bit IO addressing support */
+	writew(PCI_IO_RANGE_TYPE_32 | (PCI_IO_RANGE_TYPE_32 << 8),
+			pp->dbi_base + PCI_IO_BASE);
+	/*
+	 * PCIe access errors that result into OCP errors are caught by ARM as
+	 * "External aborts" (Precise).
+	 */
+	hook_fault_code(17, keystone_pcie_fault, SIGBUS, 0,
+			"external abort on linefetch");
+}
+
+static int ks_pcie_link_up(struct pcie_port *pp)
+{
+	struct keystone_pcie *ks_pcie = to_keystone_pcie(pp);
+	u32 val;
+
+	if (ks_pcie->en_link_train) {
+		/*
+		 * KeyStone devices do not support h/w autonomous
+		 * link up-training to GEN2 from GEN1 in either EP/RC modes.
+		 * The software needs to initiate speed change.
+		 */
+		val = readl(pp->dbi_base + PL_GEN2);
+		writel(val | DIR_SPD, pp->dbi_base + PL_GEN2);
+		/*
+		 * Initiate Link Training. We will delay for L0 as specified by
+		 * standard, but will still proceed and return success
+		 * irrespective of L0 status as this will be handled by explicit
+		 * L0 state checks during enumeration.
+		 */
+		val = readl(ks_pcie->va_reg_app + CMD_STATUS);
+		writel(LTSSM_EN_VAL | val,  ks_pcie->va_reg_app + CMD_STATUS);
+
+	}
+
+	val = readl(pp->dbi_base + DEBUG0);
+	return (val & LTSSM_STATE_MASK) == LTSSM_STATE_L0;
+}
+
+/**
+ * ks_pcie_setup_config_addr() - Set up configuration space address for a
+ * device
+ *
+ * @pp: ptr to pcie_port structure
+ * @bus: Bus number the device is residing on
+ * @device: Device number
+ * @function: Function number in device
+ *
+ * Forms and returns the address of configuration space mapped in PCIESS
+ * address space 0. Also configures CFG_SETUP for remote configuration space
+ * access.
+ *
+ * The address space has two regions to access configuration - local and remote.
+ * We access local region for bus 0 (as RC is attached on bus 0) and remote
+ * region for others with TYPE 1 access when bus > 1. As for device on bus = 1,
+ * we will do TYPE 0 access as it will be on our secondary bus (logical).
+ * CFG_SETUP is needed only for remote configuration access.
+ */
+static inline void __iomem *
+ks_pcie_setup_config_addr(struct pcie_port *pp,
+			u8 bus, u8 device, u8 function)
+{
+	struct keystone_pcie *ks_pcie = to_keystone_pcie(pp);
+	u32 regval;
+
+	if (!ks_pcie)
+		return ks_pcie;
+
+	if (bus == 0)
+		return pp->dbi_base;
+
+	regval = (bus << 16) | (device << 8) | function;
+	/*
+	 * Since Bus#1 will be a virtual bus, we need to have TYPE0
+	 * access only.
+	 * TYPE 1
+	 */
+	if (bus != 1)
+		regval |= BIT(24);
+
+	writel(regval, ks_pcie->va_reg_app + CFG_SETUP);
+	return pp->dbi_base + SPACE0_REMOTE_CFG_OFFSET;
+}
+
+static int ks_pcie_rd_other_conf(struct pcie_port *pp,
+		struct pci_bus *bus, unsigned int devfn, int where,
+		int size, u32 *val)
+{
+	struct keystone_pcie *ks_pcie = to_keystone_pcie(pp);
+	u8 bus_num = bus->number;
+	void __iomem *addr;
+	int ret;
+
+	if (!ks_pcie) {
+		dev_err(pp->dev, ": Can't get driver data\n");
+		return PCIBIOS_DEVICE_NOT_FOUND;
+	}
+
+	addr = ks_pcie_setup_config_addr(pp, bus_num, PCI_SLOT(devfn),
+				 PCI_FUNC(devfn));
+
+	ret = cfg_read(addr + (where & ~0x3), where, size, val);
+	return ret;
+}
+
+static int ks_pcie_wr_other_conf(struct pcie_port *pp,
+		struct pci_bus *bus, unsigned int devfn, int where,
+		int size, u32 val)
+{
+	struct keystone_pcie *ks_pcie = to_keystone_pcie(pp);
+	u8 bus_num = bus->number;
+	void __iomem *addr;
+
+	if (!ks_pcie) {
+		dev_err(pp->dev,
+			"ks_pcie_wr_other_conf: Can't get driver data\n");
+		return PCIBIOS_DEVICE_NOT_FOUND;
+	}
+
+	addr = ks_pcie_setup_config_addr(pp, bus_num, PCI_SLOT(devfn),
+				PCI_FUNC(devfn));
+	return cfg_write(addr + (where & ~0x3), where, size, val);
+}
+
+/**
+ * ks_pcie_set_inbound_trans() - Setup inbound access
+ *
+ * Configure BAR0 for inbound access. BAR0 is set up in h/w to have
+ * access to PCIESS application register space and just needs to set up
+ * inbound address (mainly used for MSI).
+ */
+static void ks_pcie_set_inbound_trans(struct pcie_port *pp)
+{
+	struct keystone_pcie *ks_pcie = to_keystone_pcie(pp);
+
+	/* Configure and set up BAR0 */
+	ks_pcie_set_dbi_mode(ks_pcie->va_reg_app);
+
+	/* Enable BAR0 */
+	writel(1, pp->dbi_base + PCI_BASE_ADDRESS_0);
+	writel(SZ_4K - 1, pp->dbi_base + PCI_BASE_ADDRESS_0);
+
+	ks_pcie_clear_dbi_mode(ks_pcie->va_reg_app);
+
+	 /*
+	  * For BAR0, just setting bus address for inbound writes (MSI) should
+	  * be sufficient. Use physical address to avoid any conflicts.
+	  */
+	writel(ks_pcie->reg_app.start, pp->dbi_base + PCI_BASE_ADDRESS_0);
+}
+
+static u32 ks_get_msi_data(struct pcie_port *pp)
+{
+	struct keystone_pcie *ks_pcie = to_keystone_pcie(pp);
+
+	return ks_pcie->reg_app.start + MSI_IRQ;
+}
+
+static struct pcie_host_ops keystone_pcie_host_ops = {
+	.rd_other_conf = ks_pcie_rd_other_conf,
+	.wr_other_conf = ks_pcie_wr_other_conf,
+	.link_up = ks_pcie_link_up,
+	.host_init = ks_pcie_host_init,
+	.get_msi_data = ks_get_msi_data,
+};
+
+struct pci_bus *ks_pcie_scan_bus(int nr, struct pci_sys_data *sys)
+{
+	struct pcie_port *pp = sys_to_pcie(sys);
+	struct pci_bus *bus;
+
+	bus = dw_pcie_scan_bus(nr, sys);
+	if (bus)
+		ks_pcie_set_inbound_trans(pp);
+	return bus;
+}
+
+static int ks_pcie_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
+{
+	struct pcie_port *pp = sys_to_pcie(dev->bus->sysdata);
+	struct keystone_pcie *ks_pcie = to_keystone_pcie(pp);
+
+	dev_info(pp->dev, "ks_pcie_map_irq: pin %d\n", pin);
+
+	if (!pin || pin > ks_pcie->num_legacy_host_irqs) {
+		dev_err(pp->dev, "pci irq pin out of range\n");
+		return -1;
+	}
+
+	/* pin has values from 1-4 */
+	return (ks_pcie->virqs[pin - 1] >= 0) ?
+		ks_pcie->virqs[pin - 1] : -1;
+}
+
+static struct hw_pci keystone_pcie_hw = {
+	.nr_controllers	= 1,
+	.setup		= dw_pcie_setup,
+	.scan		= ks_pcie_scan_bus,
+	.swizzle        = pci_common_swizzle,
+	.add_bus	= dw_pcie_add_bus,
+	.map_irq	= ks_pcie_map_irq,
+};
+
+static void ack_irq(struct irq_data *d)
+{
+}
+
+static void mask_irq(struct irq_data *d)
+{
+}
+
+static void unmask_irq(struct irq_data *d)
+{
+}
+
+static struct irq_chip ks_pcie_legacy_irq_chip = {
+	.name = "PCIe-LEGACY-IRQ",
+	.irq_ack = ack_irq,
+	.irq_mask = mask_irq,
+	.irq_unmask = unmask_irq,
+};
+
+static int add_pcie_port(struct keystone_pcie *ks_pcie,
+			 struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct pcie_port *pp = &ks_pcie->pp;
+	struct device *dev = &pdev->dev;
+	struct resource *res;
+	int ret, i;
+
+	/*
+	 * support upto MAX_LEGACY_HOST_IRQS host and legacy IRQs.
+	 * In dt from index 0 to 3
+	 */
+	for (i = 0; i < MAX_LEGACY_HOST_IRQS; i++) {
+		ks_pcie->legacy_host_irqs[i] = irq_of_parse_and_map(np, i);
+		if (ks_pcie->legacy_host_irqs[i] < 0)
+			break;
+		ks_pcie->num_legacy_host_irqs++;
+	}
+
+	if (ks_pcie->num_legacy_host_irqs) {
+		ks_pcie->legacy_irqd = irq_domain_add_linear(np,
+					ks_pcie->num_legacy_host_irqs,
+					&irq_domain_simple_ops, NULL);
+
+		if (!ks_pcie->legacy_irqd) {
+			dev_err(dev,
+				"Failed to add irq domain for legacy irqs\n");
+			return -EINVAL;
+		}
+	}
+
+	for (i = 0; i < ks_pcie->num_legacy_host_irqs; i++) {
+		ks_pcie->virqs[i] =
+			irq_create_mapping(ks_pcie->legacy_irqd, i);
+		irq_set_chip_and_handler(ks_pcie->virqs[i],
+			&ks_pcie_legacy_irq_chip, handle_level_irq);
+		irq_set_chip_data(ks_pcie->virqs[i], ks_pcie);
+		set_irq_flags(ks_pcie->virqs[i], IRQF_VALID);
+
+		if (ks_pcie->legacy_host_irqs[i] >= 0) {
+			irq_set_handler_data(ks_pcie->legacy_host_irqs[i],
+				ks_pcie);
+			irq_set_chained_handler(ks_pcie->legacy_host_irqs[i],
+				ks_pcie_legacy_irq_handler);
+		}
+		set_irq_flags(ks_pcie->legacy_host_irqs[i], IRQF_VALID);
+	}
+
+	if (IS_ENABLED(CONFIG_PCI_MSI)) {
+		/*
+		 * support upto 32 MSI irqs mapped to 8 host IRQs.
+		 * In dt from index 4 to 11
+		 */
+		for (i = 0; i < MAX_MSI_HOST_IRQS; i++) {
+			ks_pcie->msi_host_irqs[i] =
+				irq_of_parse_and_map(np,
+					ks_pcie->num_legacy_host_irqs + i);
+			if (ks_pcie->msi_host_irqs[i] < 0)
+				break;
+			ks_pcie->num_msi_host_irqs++;
+		}
+	}
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "reg_rc_app");
+	if (!res) {
+
+		dev_err(dev, "missing dbics base resource\n");
+		return -EINVAL;
+	}
+	ks_pcie->reg_app = *res;
+	ks_pcie->va_reg_app = devm_ioremap_nocache(dev, res->start,
+					resource_size(res));
+
+	if (!ks_pcie->va_reg_app) {
+		dev_err(dev, "ioremap failed\n");
+		return -ENODEV;
+	}
+
+	pp->root_bus_nr = -1;
+	pp->version = DW_VERSION_PRE_3_70;
+	pp->ops = &keystone_pcie_host_ops;
+	spin_lock_init(&pp->conf_lock);
+	ret = dw_pcie_host_init(pp, &keystone_pcie_hw, &msi_domain_ops);
+	if (ret) {
+		dev_err(dev, "failed to initialize host\n");
+		return ret;
+	}
+	return ret;
+}
+
+static const struct of_device_id ks_pcie_of_match[] = {
+	{
+		.type = "pci",
+		.compatible = "ti,keystone2-pcie",
+		.data =  &keystone2_data,
+	},
+	{},
+};
+MODULE_DEVICE_TABLE(of, ks_pcie_of_match);
+
+static int __exit ks_pcie_remove(struct platform_device *pdev)
+{
+	struct keystone_pcie *ks_pcie = platform_get_drvdata(pdev);
+
+	clk_disable_unprepare(ks_pcie->clk);
+	return 0;
+}
+
+static int __init ks_pcie_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct device *dev = &pdev->dev;
+	const struct of_device_id *match;
+	struct keystone_pcie *ks_pcie;
+	struct pcie_port *pp;
+	int ret = 0;
+
+	ks_pcie = devm_kzalloc(&pdev->dev, sizeof(*ks_pcie),
+				GFP_KERNEL);
+	if (!ks_pcie) {
+		dev_err(dev, "no memory for keystone pcie\n");
+		return -ENOMEM;
+	}
+
+	match = of_match_device(of_match_ptr(ks_pcie_of_match), dev);
+	ks_pcie->pdata = match ? match->data : 0;
+	if (ks_pcie->pdata) {
+		if (ks_pcie->pdata->setup)
+			ret = ks_pcie->pdata->setup(pdev);
+		if (ret < 0)
+			return -ENODEV;
+	}
+
+	/* check if we need to enable link training */
+	ks_pcie->en_link_train =
+		(of_get_property(np, "ti,enable-linktrain", NULL) != NULL);
+
+	pp = &ks_pcie->pp;
+	pp->dev = &pdev->dev;
+
+	ks_pcie->clk = devm_clk_get(&pdev->dev, "pcie");
+	if (IS_ERR(ks_pcie->clk)) {
+		dev_err(&pdev->dev, "Failed to get pcie rc clock\n");
+		return PTR_ERR(ks_pcie->clk);
+	}
+	ret = clk_prepare_enable(ks_pcie->clk);
+	if (ret)
+		return ret;
+
+	ret = add_pcie_port(ks_pcie, pdev);
+	if (ret < 0)
+		goto fail_clk;
+
+	platform_set_drvdata(pdev, ks_pcie);
+	return 0;
+
+fail_clk:
+	clk_disable_unprepare(ks_pcie->clk);
+	return ret;
+}
+
+static struct platform_driver ks_pcie_driver = {
+	.remove		= __exit_p(ks_pcie_remove),
+	.driver = {
+		.name	= "keystone-pcie",
+		.owner	= THIS_MODULE,
+		.of_match_table = of_match_ptr(ks_pcie_of_match),
+	},
+};
+
+/* Keystone PCIe driver does not allow module unload */
+static int __init ks_pcie_init(void)
+{
+	return platform_driver_probe(&ks_pcie_driver, ks_pcie_probe);
+}
+subsys_initcall(ks_pcie_init);
+
+MODULE_AUTHOR("Murali Karicheri <m-karicheri2@ti.com>");
+MODULE_DESCRIPTION("Keystone PCIe host controller driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/pci/host/pcie-ks-pdata.h b/drivers/pci/host/pcie-ks-pdata.h
new file mode 100644
index 0000000..a7626de
--- /dev/null
+++ b/drivers/pci/host/pcie-ks-pdata.h
@@ -0,0 +1,19 @@ 
+/*
+ * Copyright (C) 2013-2014 Texas Instruments., Ltd.
+ *		http://www.ti.com
+ *
+ * Author: Murali Karicheri <m-karicheri2@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+/* platform specific setup for k2 pcie */
+int k2_pcie_platform_setup(struct platform_device *pdev);
+
+/* keystone pcie pdata configurations */
+struct keystone_pcie_pdata {
+	int (*setup)(struct platform_device *pdev);
+};
+
diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 3a02717..7c3f777 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -3461,3 +3461,15 @@  int pci_dev_specific_acs_enabled(struct pci_dev *dev, u16 acs_flags)
 
 	return -ENOTTY;
 }
+
+#ifdef CONFIG_PCIE_KEYSTONE
+/*
+ * The KeyStone PCIe controller has maximum read request size of 256 bytes.
+ * Force this configuration for all EP including bridges.
+ */
+static void quirk_limit_readrequest(struct pci_dev *dev)
+{
+	pcie_set_readrq(dev, 256);
+}
+DECLARE_PCI_FIXUP_FINAL(PCI_ANY_ID, PCI_ANY_ID, quirk_limit_readrequest);
+#endif /* CONFIG_TI_KEYSTONE_PCIE */