diff mbox

[v2,12/17] sh: Add PCI host bridge driver for SH7751

Message ID 1465714475-24111-13-git-send-email-ysato@users.sourceforge.jp
State Superseded
Headers show

Commit Message

Yoshinori Sato June 12, 2016, 6:54 a.m. UTC
This is alternative SH7751 PCI driver.
Existing driver (arch/sh/drivers/pci/pci-sh7751) use SH specific interface.
But this driver using common PCI interface. It more mordan and generic.

Signed-off-by: Yoshinori Sato <ysato@users.sourceforge.jp>
---
 .../devicetree/bindings/pci/sh7751-pci.txt         |  51 +++
 arch/sh/boards/Kconfig                             |   1 +
 drivers/pci/host/Kconfig                           |   7 +
 drivers/pci/host/Makefile                          |   1 +
 drivers/pci/host/pci-sh7751.c                      | 443 +++++++++++++++++++++
 5 files changed, 503 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/pci/sh7751-pci.txt
 create mode 100644 drivers/pci/host/pci-sh7751.c

Comments

Geert Uytterhoeven June 13, 2016, 8:04 a.m. UTC | #1
On Sun, Jun 12, 2016 at 8:54 AM, Yoshinori Sato
<ysato@users.sourceforge.jp> wrote:
> This is alternative SH7751 PCI driver.

an alternative

> Existing driver (arch/sh/drivers/pci/pci-sh7751) use SH specific interface.

uses

> But this driver using common PCI interface. It more mordan and generic.

uses ... it is more modern ...

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds
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Arnd Bergmann June 13, 2016, 8:38 a.m. UTC | #2
On Sunday, June 12, 2016 3:54:30 PM CEST Yoshinori Sato wrote:
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/pci/sh7751-pci.txt
> +		ranges = <0x02000000 0x00000000 0xfd000000 0xfd000000 0x00000000 0x01000000>,
> +		         <0x01000000 0x00000000 0xfe240000 0x00000000 0x00000000 0x00040000>;
> +		reg = <0xfe200000 0x0400>,
> +		      <0x0c000000 0x04000000>,
> +		      <0xff800000 0x0030>;
> +		#interrupt-cells = <1>;
> +		interrupt-map-mask = <0x1800 0 7>;
> +		interrupt-map = <0x0000 0 1 &cpldintc evt2irq(0x2a0) 0
> +		                 0x0000 0 2 &cpldintc evt2irq(0x2c0) 0
> +		                 0x0000 0 3 &cpldintc evt2irq(0x2e0) 0
> +		                 0x0000 0 4 &cpldintc evt2irq(0x300) 0
> +
> +		                 0x0800 0 1 &cpldintc evt2irq(0x2c0) 0
> +		                 0x0800 0 2 &cpldintc evt2irq(0x2e0) 0
> +		                 0x0800 0 3 &cpldintc evt2irq(0x300) 0
> +		                 0x0800 0 4 &cpldintc evt2irq(0x2a0) 0

Is this not the default swizzling? I would guess that you can just
list the interrupt once.

The formatting is slightly inconsistent here, my recommendation is
to always enclose each entry in '< >' so you have a comma-separated
list.

> +
> +#define pcic_writel(val, reg) __raw_writel(val, pci_reg_base + (reg))
> +#define pcic_readl(reg) __raw_readl(pci_reg_base + (reg))

We generally try not to use __raw_*() accessors in drivers, because
they are not portable, lack barriers and atomicity, and don't work
when you change endianess.

> +unsigned long PCIBIOS_MIN_IO;
> +unsigned long PCIBIOS_MIN_MEM;

These should probably be in architecture code, otherwise you cannot
build more than one such driver into the kernel.

> +DEFINE_RAW_SPINLOCK(pci_config_lock);

This seems unnecessary, the config operations are always called
under a spinlock already.

> +static __initconst const struct fixups {
> +	char *compatible;
> +	void (*fixup)(void __iomem *, void __iomem *);
> +} fixup_list[] = {
> +	{
> +		.compatible = "iodata,landisk",
> +		.fixup = landisk_fixup,
> +	},
> +};

Just move the fixup pointer into the existing of match table
as the .data pointer, or add a structure to which .data
points.

> +/*
> + * Functions for accessing PCI configuration space with type 1 accesses
> + */
> +static int sh4_pci_read(struct pci_bus *bus, unsigned int devfn,
> +			   int where, int size, u32 *val)
> +{
> +	struct gen_pci *pci = bus->sysdata;
> +	void __iomem *pci_reg_base;
> +	unsigned long flags;
> +	u32 data;
> +
> +	pci_reg_base = ioremap(pci->cfg.res.start,
> +			       pci->cfg.res.end - pci->cfg.res.start);

You cannot call normally ioremap from pci_read, because it
gets called under a spinlock and ioremap can normally sleep
(that might be architecture specific).

Better map it a probe time, or use fixmap.

> +	/*
> +	 * PCIPDR may only be accessed as 32 bit words,
> +	 * so we must do byte alignment by hand
> +	 */
> +	raw_spin_lock_irqsave(&pci_config_lock, flags);
> +	pcic_writel(CONFIG_CMD(bus, devfn, where), SH4_PCIPAR);
> +	data = pcic_readl(SH4_PCIPDR);
> +	raw_spin_unlock_irqrestore(&pci_config_lock, flags);

This is shorter to express this using a 'map' function
in pci_ops combined with pci_generic_config_read32
and pci_generic_config_write32.

> +/*
> + * Called after each bus is probed, but before its children
> + * are examined.
> + */
> +void pcibios_fixup_bus(struct pci_bus *bus)
> +{
> +}

This doesn't really belong into the driver.

> +/*
> + * We need to avoid collisions with `mirrored' VGA ports
> + * and other strange ISA hardware, so we always want the
> + * addresses to be allocated in the 0x000-0x0ff region
> + * modulo 0x400.
> + */
> +resource_size_t pcibios_align_resource(void *data,
> +				       const struct resource *res,
> +				       resource_size_t size,
> +				       resource_size_t align)
> +{
> +	resource_size_t start = res->start;
> +
> +	return start;
> +}

The comment does not match what the function does, you should
change one or the other. Also move it to the same file as
pcibios_fixup_bus.

> +int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
> +			enum pci_mmap_state mmap_state, int write_combine)
> +{
> +	/*
> +	 * I/O space can be accessed via normal processor loads and stores on
> +	 * this platform but for now we elect not to do this and portable
> +	 * drivers should not do this anyway.
> +	 */
> +
> +	if (mmap_state == pci_mmap_io)
> +		return -EINVAL;
> +
> +	/*
> +	 * Ignore write-combine; for now only return uncached mappings.
> +	 */
> +	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
> +
> +	return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
> +			       vma->vm_end - vma->vm_start,
> +			       vma->vm_page_prot);
> +}

Do you actually need HAVE_PCI_MMAP? Maybe you can just unset that
and remove the function here.

> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	pci_reg_base = ioremap(res->start, res->end - res->start);
> +	if (IS_ERR(pci_reg_base))
> +		return PTR_ERR(pci_reg_base);
> +
> +	wres = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> +	if (IS_ERR(wres))
> +		return PTR_ERR(wres);
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
> +	bcr = devm_ioremap_resource(&pdev->dev, res);
> +	if (IS_ERR(bcr))


You map three distinct memory resources here, but your
binding just describes one as "reg: base address and
length of the PCI controller registers".

If there are multiple register ranges, please list each
one in the binding and document in which order they
are expected, or use named resources and list the required
names.

	Arnd
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Yoshinori Sato June 13, 2016, 3:23 p.m. UTC | #3
On Mon, 13 Jun 2016 17:38:28 +0900,
Arnd Bergmann wrote:
> 
> On Sunday, June 12, 2016 3:54:30 PM CEST Yoshinori Sato wrote:
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/pci/sh7751-pci.txt
> > +		ranges = <0x02000000 0x00000000 0xfd000000 0xfd000000 0x00000000 0x01000000>,
> > +		         <0x01000000 0x00000000 0xfe240000 0x00000000 0x00000000 0x00040000>;
> > +		reg = <0xfe200000 0x0400>,
> > +		      <0x0c000000 0x04000000>,
> > +		      <0xff800000 0x0030>;
> > +		#interrupt-cells = <1>;
> > +		interrupt-map-mask = <0x1800 0 7>;
> > +		interrupt-map = <0x0000 0 1 &cpldintc evt2irq(0x2a0) 0
> > +		                 0x0000 0 2 &cpldintc evt2irq(0x2c0) 0
> > +		                 0x0000 0 3 &cpldintc evt2irq(0x2e0) 0
> > +		                 0x0000 0 4 &cpldintc evt2irq(0x300) 0
> > +
> > +		                 0x0800 0 1 &cpldintc evt2irq(0x2c0) 0
> > +		                 0x0800 0 2 &cpldintc evt2irq(0x2e0) 0
> > +		                 0x0800 0 3 &cpldintc evt2irq(0x300) 0
> > +		                 0x0800 0 4 &cpldintc evt2irq(0x2a0) 0
> 
> Is this not the default swizzling? I would guess that you can just
> list the interrupt once.
> 
> The formatting is slightly inconsistent here, my recommendation is
> to always enclose each entry in '< >' so you have a comma-separated
> list.

OK.
I'll fix this.

> > +
> > +#define pcic_writel(val, reg) __raw_writel(val, pci_reg_base + (reg))
> > +#define pcic_readl(reg) __raw_readl(pci_reg_base + (reg))
> 
> We generally try not to use __raw_*() accessors in drivers, because
> they are not portable, lack barriers and atomicity, and don't work
> when you change endianess.

OK.
It cpied old style driver.
Update ioread/write.

> > +unsigned long PCIBIOS_MIN_IO;
> > +unsigned long PCIBIOS_MIN_MEM;
> 
> These should probably be in architecture code, otherwise you cannot
> build more than one such driver into the kernel.
> 
> > +DEFINE_RAW_SPINLOCK(pci_config_lock);
> 
> This seems unnecessary, the config operations are always called
> under a spinlock already.

OK.
remove it.

> > +static __initconst const struct fixups {
> > +	char *compatible;
> > +	void (*fixup)(void __iomem *, void __iomem *);
> > +} fixup_list[] = {
> > +	{
> > +		.compatible = "iodata,landisk",
> > +		.fixup = landisk_fixup,
> > +	},
> > +};
> 
> Just move the fixup pointer into the existing of match table
> as the .data pointer, or add a structure to which .data
> points.

OK.

> > +/*
> > + * Functions for accessing PCI configuration space with type 1 accesses
> > + */
> > +static int sh4_pci_read(struct pci_bus *bus, unsigned int devfn,
> > +			   int where, int size, u32 *val)
> > +{
> > +	struct gen_pci *pci = bus->sysdata;
> > +	void __iomem *pci_reg_base;
> > +	unsigned long flags;
> > +	u32 data;
> > +
> > +	pci_reg_base = ioremap(pci->cfg.res.start,
> > +			       pci->cfg.res.end - pci->cfg.res.start);
> 
> You cannot call normally ioremap from pci_read, because it
> gets called under a spinlock and ioremap can normally sleep
> (that might be architecture specific).
> 
> Better map it a probe time, or use fixmap.

OK.

> > +	/*
> > +	 * PCIPDR may only be accessed as 32 bit words,
> > +	 * so we must do byte alignment by hand
> > +	 */
> > +	raw_spin_lock_irqsave(&pci_config_lock, flags);
> > +	pcic_writel(CONFIG_CMD(bus, devfn, where), SH4_PCIPAR);
> > +	data = pcic_readl(SH4_PCIPDR);
> > +	raw_spin_unlock_irqrestore(&pci_config_lock, flags);
> 
> This is shorter to express this using a 'map' function
> in pci_ops combined with pci_generic_config_read32
> and pci_generic_config_write32.

OK.

> > +/*
> > + * Called after each bus is probed, but before its children
> > + * are examined.
> > + */
> > +void pcibios_fixup_bus(struct pci_bus *bus)
> > +{
> > +}
> 
> This doesn't really belong into the driver.

OK.

> > +/*
> > + * We need to avoid collisions with `mirrored' VGA ports
> > + * and other strange ISA hardware, so we always want the
> > + * addresses to be allocated in the 0x000-0x0ff region
> > + * modulo 0x400.
> > + */
> > +resource_size_t pcibios_align_resource(void *data,
> > +				       const struct resource *res,
> > +				       resource_size_t size,
> > +				       resource_size_t align)
> > +{
> > +	resource_size_t start = res->start;
> > +
> > +	return start;
> > +}
> 
> The comment does not match what the function does, you should
> change one or the other. Also move it to the same file as
> pcibios_fixup_bus.

OK.
This part copied old driver.
I will cleanup.

> > +int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
> > +			enum pci_mmap_state mmap_state, int write_combine)
> > +{
> > +	/*
> > +	 * I/O space can be accessed via normal processor loads and stores on
> > +	 * this platform but for now we elect not to do this and portable
> > +	 * drivers should not do this anyway.
> > +	 */
> > +
> > +	if (mmap_state == pci_mmap_io)
> > +		return -EINVAL;
> > +
> > +	/*
> > +	 * Ignore write-combine; for now only return uncached mappings.
> > +	 */
> > +	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
> > +
> > +	return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
> > +			       vma->vm_end - vma->vm_start,
> > +			       vma->vm_page_prot);
> > +}
> 
> Do you actually need HAVE_PCI_MMAP? Maybe you can just unset that
> and remove the function here.

Not set this.
Remove function.

> > +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > +	pci_reg_base = ioremap(res->start, res->end - res->start);
> > +	if (IS_ERR(pci_reg_base))
> > +		return PTR_ERR(pci_reg_base);
> > +
> > +	wres = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> > +	if (IS_ERR(wres))
> > +		return PTR_ERR(wres);
> > +
> > +	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
> > +	bcr = devm_ioremap_resource(&pdev->dev, res);
> > +	if (IS_ERR(bcr))
> 
> 
> You map three distinct memory resources here, but your
> binding just describes one as "reg: base address and
> length of the PCI controller registers".

OK.

> If there are multiple register ranges, please list each
> one in the binding and document in which order they
> are expected, or use named resources and list the required
> names.
>

This controller have single register area.
I will fix dts.

Thanks.

> 	Arnd
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/pci/sh7751-pci.txt b/Documentation/devicetree/bindings/pci/sh7751-pci.txt
new file mode 100644
index 0000000..c3ec71a
--- /dev/null
+++ b/Documentation/devicetree/bindings/pci/sh7751-pci.txt
@@ -0,0 +1,51 @@ 
+* Renesas SH7751 PCI host interfaces
+
+Required properties:
+  - compatible: "renesas,sh7751-pci" is required.
+    And board specific compatible if fixup required.
+
+  - reg: base address and length of the PCI controller registers.
+  - #address-cells: set to <2>
+  - #size-cells: set to <1>
+  - bus-range: PCI bus numbers covered
+  - device_type: set to "pci"
+  - ranges: ranges for the PCI memory and I/O regions.
+  - interrupt-map-mask and interrupt-map: standard PCI properties
+	to define the mapping of the PCI interface to interrupt
+	numbers.
+
+Example:
+	pci: pci-controller@fe200000 {
+		compatible = "renesas,sh7751-pci", "iodata,landisk";
+		device_type = "pci";
+		bus-range = <0 0>;
+		#address-cells = <2>;
+		#size-cells = <1>;
+		ranges = <0x02000000 0x00000000 0xfd000000 0xfd000000 0x00000000 0x01000000>,
+		         <0x01000000 0x00000000 0xfe240000 0x00000000 0x00000000 0x00040000>;
+		reg = <0xfe200000 0x0400>,
+		      <0x0c000000 0x04000000>,
+		      <0xff800000 0x0030>;
+		#interrupt-cells = <1>;
+		interrupt-map-mask = <0x1800 0 7>;
+		interrupt-map = <0x0000 0 1 &cpldintc evt2irq(0x2a0) 0
+		                 0x0000 0 2 &cpldintc evt2irq(0x2c0) 0
+		                 0x0000 0 3 &cpldintc evt2irq(0x2e0) 0
+		                 0x0000 0 4 &cpldintc evt2irq(0x300) 0
+
+		                 0x0800 0 1 &cpldintc evt2irq(0x2c0) 0
+		                 0x0800 0 2 &cpldintc evt2irq(0x2e0) 0
+		                 0x0800 0 3 &cpldintc evt2irq(0x300) 0
+		                 0x0800 0 4 &cpldintc evt2irq(0x2a0) 0
+
+		                 0x1000 0 1 &cpldintc evt2irq(0x2e0) 0
+		                 0x1000 0 2 &cpldintc evt2irq(0x300) 0
+		                 0x1000 0 3 &cpldintc evt2irq(0x2a0) 0
+		                 0x1000 0 4 &cpldintc evt2irq(0x2c0) 0
+
+		                 0x1800 0 1 &cpldintc evt2irq(0x300) 0
+		                 0x1800 0 2 &cpldintc evt2irq(0x2a0) 0
+		                 0x1800 0 3 &cpldintc evt2irq(0x2c0) 0
+		                 0x1800 0 4 &cpldintc evt2irq(0x2e0) 0>;
+	};
+};
diff --git a/arch/sh/boards/Kconfig b/arch/sh/boards/Kconfig
index b6ff9df..cfde921 100644
--- a/arch/sh/boards/Kconfig
+++ b/arch/sh/boards/Kconfig
@@ -14,6 +14,7 @@  config SH_DEVICE_TREE
 	select GENERIC_CALIBRATE_DELAY
 	select GENERIC_IOMAP
 	select COMMON_CLK
+	select SYS_SUPPORTS_PCI
 	help
 	  Select Board Described by Device Tree to build a kernel that
 	  does not hard-code any board-specific knowledge but instead uses
diff --git a/drivers/pci/host/Kconfig b/drivers/pci/host/Kconfig
index 7a0780d..a8596db 100644
--- a/drivers/pci/host/Kconfig
+++ b/drivers/pci/host/Kconfig
@@ -231,4 +231,11 @@  config PCI_HOST_THUNDER_ECAM
 	help
 	  Say Y here if you want ECAM support for CN88XX-Pass-1.x Cavium Thunder SoCs.
 
+config PCI_SH7751
+	bool "Renesas SH7751 On-Chip PCI controller"
+	depends on OF && SUPERH
+	select PCI_HOST_COMMON
+	help
+	  Say Y here if you want PCI support on SH7751.
+
 endmenu
diff --git a/drivers/pci/host/Makefile b/drivers/pci/host/Makefile
index d85b5fa..91268cb 100644
--- a/drivers/pci/host/Makefile
+++ b/drivers/pci/host/Makefile
@@ -28,3 +28,4 @@  obj-$(CONFIG_PCI_HISI) += pcie-hisi.o
 obj-$(CONFIG_PCIE_QCOM) += pcie-qcom.o
 obj-$(CONFIG_PCI_HOST_THUNDER_ECAM) += pci-thunder-ecam.o
 obj-$(CONFIG_PCI_HOST_THUNDER_PEM) += pci-thunder-pem.o
+obj-$(CONFIG_PCI_SH7751) += pci-sh7751.o
diff --git a/drivers/pci/host/pci-sh7751.c b/drivers/pci/host/pci-sh7751.c
new file mode 100644
index 0000000..c029e5b
--- /dev/null
+++ b/drivers/pci/host/pci-sh7751.c
@@ -0,0 +1,443 @@ 
+/*
+ * SH7751 PCI driver
+ * Copyright (C) 2016 Yoshinori Sato
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_pci.h>
+#include <linux/of_platform.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include "pci-host-common.h"
+
+#define SH4_PCICR		0x100		/* PCI Control Register */
+  #define SH4_PCICR_PREFIX	  0xA5000000	/* CR prefix for write */
+  #define SH4_PCICR_FTO		  BIT(10)	/* TRDY/IRDY Enable */
+  #define SH4_PCICR_TRSB	  BIT(9)	/* Target Read Single */
+  #define SH4_PCICR_BSWP	  BIT(8)	/* Target Byte Swap */
+  #define SH4_PCICR_PLUP	  BIT(7)	/* Enable PCI Pullup */
+  #define SH4_PCICR_ARBM	  BIT(6)	/* PCI Arbitration Mode */
+#define SH4_PCICR_MD		  (BIT(4) | BIT(5))	/* MD9 and MD10 status */
+  #define SH4_PCICR_SERR	  BIT(3)	/* SERR output assert */
+  #define SH4_PCICR_INTA	  BIT(2)	/* INTA output assert */
+  #define SH4_PCICR_PRST	  BIT(1)	/* PCI Reset Assert */
+  #define SH4_PCICR_CFIN	  BIT(0)	/* Central Fun. Init Done */
+#define SH4_PCILSR0		0x104		/* PCI Local Space Register0 */
+#define SH4_PCILSR1		0x108		/* PCI Local Space Register1 */
+#define SH4_PCILAR0		0x10C		/* PCI Local Addr Register1 */
+#define SH4_PCILAR1		0x110		/* PCI Local Addr Register1 */
+#define SH4_PCIPAR		0x1C0		/* PIO Address Register */
+  #define SH4_PCIPAR_CFGEN	  0x80000000	/* Configuration Enable */
+  #define SH4_PCIPAR_BUSNO	  0x00FF0000	/* Config. Bus Number */
+  #define SH4_PCIPAR_DEVNO	  0x0000FF00	/* Config. Device Number */
+  #define SH4_PCIPAR_REGAD	  0x000000FC	/* Register Address Number */
+#define SH4_PCIMBR		0x1C4		/* Memory Base Address */
+  #define SH4_PCIMBR_MASK	  0xFF000000	/* Memory Space Mask */
+  #define SH4_PCIMBR_LOCK	  0x00000001	/* Lock Memory Space */
+#define SH4_PCIIOBR		0x1C8		/* I/O Base Address Register */
+  #define SH4_PCIIOBR_MASK	  0xFFFC0000	/* IO Space Mask */
+  #define SH4_PCIIOBR_LOCK	  0x00000001	/* Lock IO Space */
+#define SH4_PCIPINT		0x1CC		/* Power Mgmnt Int. Register */
+  #define SH4_PCIPINT_D3	  0x00000002	/* D3 Pwr Mgmt. Interrupt */
+  #define SH4_PCIPINT_D0	  0x00000001	/* D0 Pwr Mgmt. Interrupt */
+#define SH4_PCIPINTM		0x1D0		/* Power Mgmnt Mask Register */
+#define SH4_PCICLKR		0x1D4		/* Clock Ctrl. Register */
+  #define SH4_PCICLKR_PCSTP	  0x00000002	/* PCI Clock Stop */
+  #define SH4_PCICLKR_BCSTP	  0x00000001	/* BCLK Clock Stop */
+/* For definitions of BCR, MCR see ... */
+#define SH4_PCIBCR1		0x1E0		/* Memory BCR1 Register */
+  #define SH4_PCIMBR0		SH4_PCIBCR1
+#define SH4_PCIBCR2		0x1E4		/* Memory BCR2 Register */
+  #define SH4_PCIMBMR0		SH4_PCIBCR2
+#define SH4_PCIWCR1		0x1E8		/* Wait Control 1 Register */
+#define SH4_PCIWCR2		0x1EC		/* Wait Control 2 Register */
+#define SH4_PCIWCR3		0x1F0		/* Wait Control 3 Register */
+  #define SH4_PCIMBR2		SH4_PCIWCR3
+#define SH4_PCIMCR		0x1F4		/* Memory Control Register */
+#define SH4_PCIBCR3		0x1f8		/* Memory BCR3 Register */
+#define SH4_PCIPCTR             0x200		/* Port Control Register */
+  #define SH4_PCIPCTR_P2EN	  0x000400000	/* Port 2 Enable */
+  #define SH4_PCIPCTR_P1EN	  0x000200000	/* Port 1 Enable */
+  #define SH4_PCIPCTR_P0EN	  0x000100000	/* Port 0 Enable */
+  #define SH4_PCIPCTR_P2UP	  0x000000020	/* Port2 Pull Up Enable */
+  #define SH4_PCIPCTR_P2IO	  0x000000010	/* Port2 Output Enable */
+  #define SH4_PCIPCTR_P1UP	  0x000000008	/* Port1 Pull Up Enable */
+  #define SH4_PCIPCTR_P1IO	  0x000000004	/* Port1 Output Enable */
+  #define SH4_PCIPCTR_P0UP	  0x000000002	/* Port0 Pull Up Enable */
+  #define SH4_PCIPCTR_P0IO	  0x000000001	/* Port0 Output Enable */
+#define SH4_PCIPDTR		0x204		/* Port Data Register */
+  #define SH4_PCIPDTR_PB5	  0x000000020	/* Port 5 Enable */
+  #define SH4_PCIPDTR_PB4	  0x000000010	/* Port 4 Enable */
+  #define SH4_PCIPDTR_PB3	  0x000000008	/* Port 3 Enable */
+  #define SH4_PCIPDTR_PB2	  0x000000004	/* Port 2 Enable */
+  #define SH4_PCIPDTR_PB1	  0x000000002	/* Port 1 Enable */
+  #define SH4_PCIPDTR_PB0	  0x000000001	/* Port 0 Enable */
+#define SH4_PCIPDR		0x220		/* Port IO Data Register */
+
+/* Platform Specific Values */
+#define SH7751_VENDOR_ID             0x1054
+#define SH7751_DEVICE_ID             0x3505
+#define SH7751R_DEVICE_ID            0x350e
+
+/* Memory Control Registers */
+#define SH7751_BCR1                0x0000    /* Memory BCR1 Register */
+#define SH7751_BCR2                0x0004    /* Memory BCR2 Register */
+#define SH7751_BCR3                0x0050    /* Memory BCR3 Register */
+#define SH7751_WCR1                0x0008    /* Wait Control 1 Register */
+#define SH7751_WCR2                0x000C    /* Wait Control 2 Register */
+#define SH7751_WCR3                0x0010    /* Wait Control 3 Register */
+#define SH7751_MCR                 0x0014    /* Memory Control Register */
+
+/* General Memory Config Addresses */
+#define SH7751_CS0_BASE_ADDR       0x0
+#define SH7751_MEM_REGION_SIZE     0x04000000
+#define SH7751_CS1_BASE_ADDR \
+	(SH7751_CS0_BASE_ADDR + SH7751_MEM_REGION_SIZE)
+#define SH7751_CS2_BASE_ADDR \
+	(SH7751_CS1_BASE_ADDR + SH7751_MEM_REGION_SIZE)
+#define SH7751_CS3_BASE_ADDR \
+	(SH7751_CS2_BASE_ADDR + SH7751_MEM_REGION_SIZE)
+#define SH7751_CS4_BASE_ADDR \
+	(SH7751_CS3_BASE_ADDR + SH7751_MEM_REGION_SIZE)
+#define SH7751_CS5_BASE_ADDR \
+	(SH7751_CS4_BASE_ADDR + SH7751_MEM_REGION_SIZE)
+#define SH7751_CS6_BASE_ADDR \
+	(SH7751_CS5_BASE_ADDR + SH7751_MEM_REGION_SIZE)
+
+#define pcic_writel(val, reg) __raw_writel(val, pci_reg_base + (reg))
+#define pcic_readl(reg) __raw_readl(pci_reg_base + (reg))
+
+unsigned long PCIBIOS_MIN_IO;
+unsigned long PCIBIOS_MIN_MEM;
+DEFINE_RAW_SPINLOCK(pci_config_lock);
+
+/*
+ * PCIC fixups
+ */
+
+#define PCIMCR_MRSET 0x40000000
+#define PCIMCR_RFSH  0x00000004
+
+static void __init landisk_fixup(void __iomem *pci_reg_base, void __iomem *bcr)
+{
+	unsigned long bcr1, mcr;
+
+	bcr1 = __raw_readl(bcr + SH7751_BCR1);
+	bcr1 |= 0x00080000;	/* Enable Bit 19 BREQEN, set PCIC to slave */
+	pcic_writel(bcr1, SH4_PCIBCR1);
+
+	mcr = __raw_readl(bcr + SH7751_MCR);
+	mcr &= (~PCIMCR_MRSET) & (~PCIMCR_RFSH);
+	pcic_writel(mcr, SH4_PCIMCR);
+
+	pcic_writel(0x0c000000, PCI_BASE_ADDRESS_1);
+	pcic_writel(0xd0000000, PCI_BASE_ADDRESS_2);
+	pcic_writel(0x0c000000, SH4_PCILAR0);
+	pcic_writel(0x00000000, SH4_PCILAR1);
+}
+
+static __initconst const struct fixups {
+	char *compatible;
+	void (*fixup)(void __iomem *, void __iomem *);
+} fixup_list[] = {
+	{
+		.compatible = "iodata,landisk",
+		.fixup = landisk_fixup,
+	},
+};
+
+static __init void pcic_fixups(struct device_node *np,
+		       void __iomem *pcic, void __iomem *bcr)
+{
+	int i;
+	const struct fixups *f = fixup_list;
+
+	for (i = 0; i < ARRAY_SIZE(fixup_list); i++) {
+		if (of_device_is_compatible(np, f->compatible)) {
+			f->fixup(pcic, bcr);
+			break;
+		}
+	}
+}
+
+/*
+ * Direct access to PCI hardware...
+ */
+#define CONFIG_CMD(bus, devfn, where) \
+	(0x80000000 | (bus->number << 16) | (devfn << 8) | (where & ~3))
+
+/*
+ * Functions for accessing PCI configuration space with type 1 accesses
+ */
+static int sh4_pci_read(struct pci_bus *bus, unsigned int devfn,
+			   int where, int size, u32 *val)
+{
+	struct gen_pci *pci = bus->sysdata;
+	void __iomem *pci_reg_base;
+	unsigned long flags;
+	u32 data;
+
+	pci_reg_base = ioremap(pci->cfg.res.start,
+			       pci->cfg.res.end - pci->cfg.res.start);
+
+	/*
+	 * PCIPDR may only be accessed as 32 bit words,
+	 * so we must do byte alignment by hand
+	 */
+	raw_spin_lock_irqsave(&pci_config_lock, flags);
+	pcic_writel(CONFIG_CMD(bus, devfn, where), SH4_PCIPAR);
+	data = pcic_readl(SH4_PCIPDR);
+	raw_spin_unlock_irqrestore(&pci_config_lock, flags);
+
+	switch (size) {
+	case 1:
+		*val = (data >> ((where & 3) << 3)) & 0xff;
+		break;
+	case 2:
+		*val = (data >> ((where & 2) << 3)) & 0xffff;
+		break;
+	case 4:
+		*val = data;
+		break;
+	default:
+		return PCIBIOS_FUNC_NOT_SUPPORTED;
+	}
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+/*
+ * Since SH4 only does 32bit access we'll have to do a read,
+ * mask,write operation.
+ * We'll allow an odd byte offset, though it should be illegal.
+ */
+static int sh4_pci_write(struct pci_bus *bus, unsigned int devfn,
+			 int where, int size, u32 val)
+{
+	struct gen_pci *pci = bus->sysdata;
+	void __iomem *pci_reg_base;
+	unsigned long flags;
+	int shift;
+	u32 data;
+
+	pci_reg_base = ioremap(pci->cfg.res.start,
+			       pci->cfg.res.end - pci->cfg.res.start);
+
+	raw_spin_lock_irqsave(&pci_config_lock, flags);
+	pcic_writel(CONFIG_CMD(bus, devfn, where), SH4_PCIPAR);
+	data = pcic_readl(SH4_PCIPDR);
+	raw_spin_unlock_irqrestore(&pci_config_lock, flags);
+
+	switch (size) {
+	case 1:
+		shift = (where & 3) << 3;
+		data &= ~(0xff << shift);
+		data |= ((val & 0xff) << shift);
+		break;
+	case 2:
+		shift = (where & 2) << 3;
+		data &= ~(0xffff << shift);
+		data |= ((val & 0xffff) << shift);
+		break;
+	case 4:
+		data = val;
+		break;
+	default:
+		return PCIBIOS_FUNC_NOT_SUPPORTED;
+	}
+
+	pcic_writel(data, SH4_PCIPDR);
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+static struct gen_pci_cfg_bus_ops pci_sh7751_ops = {
+	.ops = {
+		.read	= sh4_pci_read,
+		.write	= sh4_pci_write,
+	},
+};
+
+/*
+ * Called after each bus is probed, but before its children
+ * are examined.
+ */
+void pcibios_fixup_bus(struct pci_bus *bus)
+{
+}
+
+/*
+ * We need to avoid collisions with `mirrored' VGA ports
+ * and other strange ISA hardware, so we always want the
+ * addresses to be allocated in the 0x000-0x0ff region
+ * modulo 0x400.
+ */
+resource_size_t pcibios_align_resource(void *data,
+				       const struct resource *res,
+				       resource_size_t size,
+				       resource_size_t align)
+{
+	resource_size_t start = res->start;
+
+	return start;
+}
+
+int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
+			enum pci_mmap_state mmap_state, int write_combine)
+{
+	/*
+	 * I/O space can be accessed via normal processor loads and stores on
+	 * this platform but for now we elect not to do this and portable
+	 * drivers should not do this anyway.
+	 */
+	if (mmap_state == pci_mmap_io)
+		return -EINVAL;
+
+	/*
+	 * Ignore write-combine; for now only return uncached mappings.
+	 */
+	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+
+	return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
+			       vma->vm_end - vma->vm_start,
+			       vma->vm_page_prot);
+}
+
+static const struct of_device_id sh7751_pci_of_match[] = {
+	{ .compatible = "renesas,sh7751-pci", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, sh7751_pci_of_match);
+
+static void __init set_pci_bcr(void __iomem *pci_reg_base,
+			       void __iomem *bcr,
+			       unsigned int area)
+{
+	unsigned long word;
+
+	word = __raw_readl(bcr + SH7751_BCR1);
+	/* check BCR for SDRAM in area */
+	if (((word >> area) & 1) == 0) {
+		pr_info("PCI: Area %d is not configured for SDRAM. BCR1=0x%lx\n",
+			area, word);
+		return;
+	}
+	pcic_writel(word, SH4_PCIBCR1);
+
+	word = __raw_readw(bcr + SH7751_BCR2);
+	/* check BCR2 for 32bit SDRAM interface*/
+	if (((word >> (area << 1)) & 0x3) != 0x3) {
+		pr_info("PCI: Area %d is not 32 bit SDRAM. BCR2=0x%lx\n",
+			area, word);
+		return;
+	}
+	pcic_writel(word, SH4_PCIBCR2);
+}
+
+static __init int sh7751_pci_probe(struct platform_device *pdev)
+{
+	struct resource *res, *wres;
+	u32 id;
+	u32 reg, word;
+	void __iomem *pci_reg_base;
+	void __iomem *bcr;
+	struct gen_pci *pci;
+
+	pci = devm_kzalloc(&pdev->dev, sizeof(*pci), GFP_KERNEL);
+	if (!pci)
+		return -ENOMEM;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	pci_reg_base = ioremap(res->start, res->end - res->start);
+	if (IS_ERR(pci_reg_base))
+		return PTR_ERR(pci_reg_base);
+
+	wres = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	if (IS_ERR(wres))
+		return PTR_ERR(wres);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
+	bcr = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(bcr))
+		return PTR_ERR(bcr);
+
+	/* check for SH7751/SH7751R hardware */
+	id = pcic_readl(PCI_VENDOR_ID);
+	if (id != ((SH7751_DEVICE_ID << 16) | SH7751_VENDOR_ID) &&
+	    id != ((SH7751R_DEVICE_ID << 16) | SH7751_VENDOR_ID)) {
+		pr_warn("PCI: This is not an SH7751(R)\n");
+		return -ENODEV;
+	}
+	dev_info(&pdev->dev, "PCI core found at %pR\n",
+		pci_reg_base);
+
+	/* Set the BCRs to enable PCI access */
+	reg = __raw_readl(bcr);
+	reg |= 0x80000;
+	__raw_writel(reg, bcr);
+
+	/* Turn the clocks back on (not done in reset)*/
+	pcic_writel(0, SH4_PCICLKR);
+	/* Clear Powerdown IRQs (not done in reset) */
+	word = SH4_PCIPINT_D3 | SH4_PCIPINT_D0;
+	pcic_writel(word, SH4_PCIPINT);
+
+	/* set the command/status bits to:
+	 * Wait Cycle Control + Parity Enable + Bus Master +
+	 * Mem space enable
+	 */
+	word = PCI_COMMAND_WAIT | PCI_COMMAND_PARITY |
+	       PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY;
+	pcic_writel(word, PCI_COMMAND);
+
+	/* define this host as the host bridge */
+	word = PCI_BASE_CLASS_BRIDGE << 24;
+	pcic_writel(word, PCI_CLASS_REVISION);
+
+	/* Set IO and Mem windows to local address
+	 * Make PCI and local address the same for easy 1 to 1 mapping
+	 */
+	word = wres->end - wres->start - 1;
+	pcic_writel(word, SH4_PCILSR0);
+	/* Set the values on window 0 PCI config registers */
+	word = P2SEGADDR(wres->start);
+	pcic_writel(word, SH4_PCILAR0);
+	pcic_writel(word, PCI_BASE_ADDRESS_1);
+
+	set_pci_bcr(pci_reg_base, bcr, (wres->start >> 27) & 0x07);
+
+	/* configure the wait control registers */
+	word = __raw_readl(bcr + SH7751_WCR1);
+	pcic_writel(word, SH4_PCIWCR1);
+	word = __raw_readl(bcr + SH7751_WCR2);
+	pcic_writel(word, SH4_PCIWCR2);
+	word = __raw_readl(bcr + SH7751_WCR3);
+	pcic_writel(word, SH4_PCIWCR3);
+	word = __raw_readl(bcr + SH7751_MCR);
+	pcic_writel(word, SH4_PCIMCR);
+
+	pcic_fixups(pdev->dev.of_node, pci_reg_base, bcr);
+
+	/*
+	 * SH7751 init done, set central function init complete
+	 * use round robin mode to stop a device starving/overruning
+	 */
+	word = SH4_PCICR_PREFIX | SH4_PCICR_CFIN | SH4_PCICR_ARBM;
+	pcic_writel(word, SH4_PCICR);
+
+	pci->cfg.ops = &pci_sh7751_ops;
+	return pci_host_common_probe(pdev, pci);
+}
+
+static __refdata struct platform_driver sh7751_pci_driver = {
+	.driver = {
+		.name = "sh7751-pci",
+		.of_match_table = sh7751_pci_of_match,
+	},
+	.probe = sh7751_pci_probe,
+};
+builtin_platform_driver(sh7751_pci_driver);