diff mbox series

[v3,04/10] PCI: apple: Add initial hardware bring-up

Message ID 20210913182550.264165-5-maz@kernel.org
State New
Headers show
Series PCI: Add support for Apple M1 | expand

Commit Message

Marc Zyngier Sept. 13, 2021, 6:25 p.m. UTC
From: Alyssa Rosenzweig <alyssa@rosenzweig.io>

Add a minimal driver to bring up the PCIe bus on Apple system-on-chips,
particularly the Apple M1. This driver exposes the internal bus used for
the USB type-A ports, Ethernet, Wi-Fi, and Bluetooth. Bringing up the
radios requires additional drivers beyond what's necessary for PCIe
itself.

At this stage, nothing is functionnal.

Co-developed-by: Stan Skowronek <stan@corellium.com>
Signed-off-by: Stan Skowronek <stan@corellium.com>
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210816031621.240268-3-alyssa@rosenzweig.io
---
 MAINTAINERS                         |   7 +
 drivers/pci/controller/Kconfig      |  12 ++
 drivers/pci/controller/Makefile     |   1 +
 drivers/pci/controller/pcie-apple.c | 243 ++++++++++++++++++++++++++++
 4 files changed, 263 insertions(+)
 create mode 100644 drivers/pci/controller/pcie-apple.c

Comments

Sven Peter Sept. 13, 2021, 8:48 p.m. UTC | #1
On Mon, Sep 13, 2021, at 20:25, Marc Zyngier wrote:
> From: Alyssa Rosenzweig <alyssa@rosenzweig.io>
> 
> Add a minimal driver to bring up the PCIe bus on Apple system-on-chips,
> particularly the Apple M1. This driver exposes the internal bus used for
> the USB type-A ports, Ethernet, Wi-Fi, and Bluetooth. Bringing up the
> radios requires additional drivers beyond what's necessary for PCIe
> itself.
> 
> At this stage, nothing is functionnal.
> 
> Co-developed-by: Stan Skowronek <stan@corellium.com>
> Signed-off-by: Stan Skowronek <stan@corellium.com>
> Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
> Signed-off-by: Marc Zyngier <maz@kernel.org>
> Link: https://lore.kernel.org/r/20210816031621.240268-3-alyssa@rosenzweig.io
> ---
>  MAINTAINERS                         |   7 +
>  drivers/pci/controller/Kconfig      |  12 ++
>  drivers/pci/controller/Makefile     |   1 +
>  drivers/pci/controller/pcie-apple.c | 243 ++++++++++++++++++++++++++++
>  4 files changed, 263 insertions(+)
>  create mode 100644 drivers/pci/controller/pcie-apple.c
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 813a847e2d64..9905cc48fed9 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -1280,6 +1280,13 @@ S:	Maintained
>  F:	Documentation/devicetree/bindings/iommu/apple,dart.yaml
>  F:	drivers/iommu/apple-dart.c
>  
> +APPLE PCIE CONTROLLER DRIVER
> +M:	Alyssa Rosenzweig <alyssa@rosenzweig.io>
> +M:	Marc Zyngier <maz@kernel.org>
> +L:	linux-pci@vger.kernel.org
> +S:	Maintained
> +F:	drivers/pci/controller/pcie-apple.c
> +
>  APPLE SMC DRIVER
>  M:	Henrik Rydberg <rydberg@bitmath.org>
>  L:	linux-hwmon@vger.kernel.org
> diff --git a/drivers/pci/controller/Kconfig b/drivers/pci/controller/Kconfig
> index 326f7d13024f..814833a8120d 100644
> --- a/drivers/pci/controller/Kconfig
> +++ b/drivers/pci/controller/Kconfig
> @@ -312,6 +312,18 @@ config PCIE_HISI_ERR
>  	  Say Y here if you want error handling support
>  	  for the PCIe controller's errors on HiSilicon HIP SoCs
>  
> +config PCIE_APPLE
> +	tristate "Apple PCIe controller"
> +	depends on ARCH_APPLE || COMPILE_TEST
> +	depends on OF
> +	depends on PCI_MSI_IRQ_DOMAIN
> +	help
> +	  Say Y here if you want to enable PCIe controller support on Apple
> +	  system-on-chips, like the Apple M1. This is required for the USB
> +	  type-A ports, Ethernet, Wi-Fi, and Bluetooth.
> +
> +	  If unsure, say Y if you have an Apple Silicon system.
> +
>  source "drivers/pci/controller/dwc/Kconfig"
>  source "drivers/pci/controller/mobiveil/Kconfig"
>  source "drivers/pci/controller/cadence/Kconfig"
> diff --git a/drivers/pci/controller/Makefile 
> b/drivers/pci/controller/Makefile
> index aaf30b3dcc14..f9d40bad932c 100644
> --- a/drivers/pci/controller/Makefile
> +++ b/drivers/pci/controller/Makefile
> @@ -37,6 +37,7 @@ obj-$(CONFIG_VMD) += vmd.o
>  obj-$(CONFIG_PCIE_BRCMSTB) += pcie-brcmstb.o
>  obj-$(CONFIG_PCI_LOONGSON) += pci-loongson.o
>  obj-$(CONFIG_PCIE_HISI_ERR) += pcie-hisi-error.o
> +obj-$(CONFIG_PCIE_APPLE) += pcie-apple.o
>  # pcie-hisi.o quirks are needed even without CONFIG_PCIE_DW
>  obj-y				+= dwc/
>  obj-y				+= mobiveil/
> diff --git a/drivers/pci/controller/pcie-apple.c 
> b/drivers/pci/controller/pcie-apple.c
> new file mode 100644
> index 000000000000..f3c414950a10
> --- /dev/null
> +++ b/drivers/pci/controller/pcie-apple.c
> @@ -0,0 +1,243 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * PCIe host bridge driver for Apple system-on-chips.
> + *
> + * The HW is ECAM compliant, so once the controller is initialized,
> + * the driver mostly deals MSI mapping and handling of per-port
> + * interrupts (INTx, management and error signals).
> + *
> + * Initialization requires enabling power and clocks, along with a
> + * number of register pokes.
> + *
> + * Copyright (C) 2021 Alyssa Rosenzweig <alyssa@rosenzweig.io>
> + * Copyright (C) 2021 Google LLC
> + * Copyright (C) 2021 Corellium LLC
> + * Copyright (C) 2021 Mark Kettenis <kettenis@openbsd.org>
> + *
> + * Author: Alyssa Rosenzweig <alyssa@rosenzweig.io>
> + * Author: Marc Zyngier <maz@kernel.org>
> + */
> +
> [...]
> +
> +static inline void rmwl(u32 clr, u32 set, void __iomem *addr)
> +{
> +	writel_relaxed((readl_relaxed(addr) & ~clr) | set, addr);
> +}

This helper is a bit strange, especially since it's always only used
with either clr != 0 or set != 0 but never (clr = 0 and set = 0) afaict.
Maybe create two instead for setting and clearing bits?

> +
> +static int apple_pcie_setup_port(struct apple_pcie *pcie,
> +				 struct device_node *np)
> +{
> +	struct platform_device *platform = to_platform_device(pcie->dev);
> +	struct apple_pcie_port *port;
> +	struct gpio_desc *reset;
> +	u32 stat, idx;
> +	int ret;
> +
> +	reset = gpiod_get_from_of_node(np, "reset-gpios", 0,
> +				       GPIOD_OUT_LOW, "#PERST");
> +	if (IS_ERR(reset))
> +		return PTR_ERR(reset);
> +
> +	port = devm_kzalloc(pcie->dev, sizeof(*port), GFP_KERNEL);
> +	if (!port)
> +		return -ENOMEM;
> +
> +	ret = of_property_read_u32_index(np, "reg", 0, &idx);
> +	if (ret)
> +		return ret;
> +
> +	/* Use the first reg entry to work out the port index */
> +	port->idx = idx >> 11;
> +	port->pcie = pcie;
> +	port->np = np;
> +
> +	port->base = devm_platform_ioremap_resource(platform, port->idx + 2);
> +	if (IS_ERR(port->base))
> +		return -ENODEV;
> +
> +	rmwl(0, PORT_APPCLK_EN, port + PORT_APPCLK);
> +
> +	rmwl(0, PORT_PERST_OFF, port->base + PORT_PERST);
> +	gpiod_set_value(reset, 1);
> +
> +	ret = readl_relaxed_poll_timeout(port->base + PORT_STATUS, stat,
> +					 stat & PORT_STATUS_READY, 100, 250000);
> +	if (ret < 0) {
> +		dev_err(pcie->dev, "port %pOF ready wait timeout\n", np);
> +		return ret;
> +	}
> +
> +	/* Flush writes and enable the link */
> +	dma_wmb();

This is a DMA barrier but there's no DMA you need to order this against
here. I think you can just drop it.

> +
> +	writel_relaxed(PORT_LTSSMCTL_START, port->base + PORT_LTSSMCTL);
> +
> +	return 0;
> +}
> +



Sven
Marc Zyngier Sept. 17, 2021, 9:20 a.m. UTC | #2
On Mon, 13 Sep 2021 21:48:47 +0100,
"Sven Peter" <sven@svenpeter.dev> wrote:
> 
> 
> 
> On Mon, Sep 13, 2021, at 20:25, Marc Zyngier wrote:
> > From: Alyssa Rosenzweig <alyssa@rosenzweig.io>
> > 
> > Add a minimal driver to bring up the PCIe bus on Apple system-on-chips,
> > particularly the Apple M1. This driver exposes the internal bus used for
> > the USB type-A ports, Ethernet, Wi-Fi, and Bluetooth. Bringing up the
> > radios requires additional drivers beyond what's necessary for PCIe
> > itself.
> > 
> > At this stage, nothing is functionnal.
> > 
> > Co-developed-by: Stan Skowronek <stan@corellium.com>
> > Signed-off-by: Stan Skowronek <stan@corellium.com>
> > Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
> > Signed-off-by: Marc Zyngier <maz@kernel.org>
> > Link: https://lore.kernel.org/r/20210816031621.240268-3-alyssa@rosenzweig.io
> > ---
> >  MAINTAINERS                         |   7 +
> >  drivers/pci/controller/Kconfig      |  12 ++
> >  drivers/pci/controller/Makefile     |   1 +
> >  drivers/pci/controller/pcie-apple.c | 243 ++++++++++++++++++++++++++++
> >  4 files changed, 263 insertions(+)
> >  create mode 100644 drivers/pci/controller/pcie-apple.c
> > 
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index 813a847e2d64..9905cc48fed9 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -1280,6 +1280,13 @@ S:	Maintained
> >  F:	Documentation/devicetree/bindings/iommu/apple,dart.yaml
> >  F:	drivers/iommu/apple-dart.c
> >  
> > +APPLE PCIE CONTROLLER DRIVER
> > +M:	Alyssa Rosenzweig <alyssa@rosenzweig.io>
> > +M:	Marc Zyngier <maz@kernel.org>
> > +L:	linux-pci@vger.kernel.org
> > +S:	Maintained
> > +F:	drivers/pci/controller/pcie-apple.c
> > +
> >  APPLE SMC DRIVER
> >  M:	Henrik Rydberg <rydberg@bitmath.org>
> >  L:	linux-hwmon@vger.kernel.org
> > diff --git a/drivers/pci/controller/Kconfig b/drivers/pci/controller/Kconfig
> > index 326f7d13024f..814833a8120d 100644
> > --- a/drivers/pci/controller/Kconfig
> > +++ b/drivers/pci/controller/Kconfig
> > @@ -312,6 +312,18 @@ config PCIE_HISI_ERR
> >  	  Say Y here if you want error handling support
> >  	  for the PCIe controller's errors on HiSilicon HIP SoCs
> >  
> > +config PCIE_APPLE
> > +	tristate "Apple PCIe controller"
> > +	depends on ARCH_APPLE || COMPILE_TEST
> > +	depends on OF
> > +	depends on PCI_MSI_IRQ_DOMAIN
> > +	help
> > +	  Say Y here if you want to enable PCIe controller support on Apple
> > +	  system-on-chips, like the Apple M1. This is required for the USB
> > +	  type-A ports, Ethernet, Wi-Fi, and Bluetooth.
> > +
> > +	  If unsure, say Y if you have an Apple Silicon system.
> > +
> >  source "drivers/pci/controller/dwc/Kconfig"
> >  source "drivers/pci/controller/mobiveil/Kconfig"
> >  source "drivers/pci/controller/cadence/Kconfig"
> > diff --git a/drivers/pci/controller/Makefile 
> > b/drivers/pci/controller/Makefile
> > index aaf30b3dcc14..f9d40bad932c 100644
> > --- a/drivers/pci/controller/Makefile
> > +++ b/drivers/pci/controller/Makefile
> > @@ -37,6 +37,7 @@ obj-$(CONFIG_VMD) += vmd.o
> >  obj-$(CONFIG_PCIE_BRCMSTB) += pcie-brcmstb.o
> >  obj-$(CONFIG_PCI_LOONGSON) += pci-loongson.o
> >  obj-$(CONFIG_PCIE_HISI_ERR) += pcie-hisi-error.o
> > +obj-$(CONFIG_PCIE_APPLE) += pcie-apple.o
> >  # pcie-hisi.o quirks are needed even without CONFIG_PCIE_DW
> >  obj-y				+= dwc/
> >  obj-y				+= mobiveil/
> > diff --git a/drivers/pci/controller/pcie-apple.c 
> > b/drivers/pci/controller/pcie-apple.c
> > new file mode 100644
> > index 000000000000..f3c414950a10
> > --- /dev/null
> > +++ b/drivers/pci/controller/pcie-apple.c
> > @@ -0,0 +1,243 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * PCIe host bridge driver for Apple system-on-chips.
> > + *
> > + * The HW is ECAM compliant, so once the controller is initialized,
> > + * the driver mostly deals MSI mapping and handling of per-port
> > + * interrupts (INTx, management and error signals).
> > + *
> > + * Initialization requires enabling power and clocks, along with a
> > + * number of register pokes.
> > + *
> > + * Copyright (C) 2021 Alyssa Rosenzweig <alyssa@rosenzweig.io>
> > + * Copyright (C) 2021 Google LLC
> > + * Copyright (C) 2021 Corellium LLC
> > + * Copyright (C) 2021 Mark Kettenis <kettenis@openbsd.org>
> > + *
> > + * Author: Alyssa Rosenzweig <alyssa@rosenzweig.io>
> > + * Author: Marc Zyngier <maz@kernel.org>
> > + */
> > +
> > [...]
> > +
> > +static inline void rmwl(u32 clr, u32 set, void __iomem *addr)
> > +{
> > +	writel_relaxed((readl_relaxed(addr) & ~clr) | set, addr);
> > +}
> 
> This helper is a bit strange, especially since it's always only used
> with either clr != 0 or set != 0 but never (clr = 0 and set = 0) afaict.
> Maybe create two instead for setting and clearing bits?

That's indeed nicer, and it makes the code more readable.

> 
> > +
> > +static int apple_pcie_setup_port(struct apple_pcie *pcie,
> > +				 struct device_node *np)
> > +{
> > +	struct platform_device *platform = to_platform_device(pcie->dev);
> > +	struct apple_pcie_port *port;
> > +	struct gpio_desc *reset;
> > +	u32 stat, idx;
> > +	int ret;
> > +
> > +	reset = gpiod_get_from_of_node(np, "reset-gpios", 0,
> > +				       GPIOD_OUT_LOW, "#PERST");
> > +	if (IS_ERR(reset))
> > +		return PTR_ERR(reset);
> > +
> > +	port = devm_kzalloc(pcie->dev, sizeof(*port), GFP_KERNEL);
> > +	if (!port)
> > +		return -ENOMEM;
> > +
> > +	ret = of_property_read_u32_index(np, "reg", 0, &idx);
> > +	if (ret)
> > +		return ret;
> > +
> > +	/* Use the first reg entry to work out the port index */
> > +	port->idx = idx >> 11;
> > +	port->pcie = pcie;
> > +	port->np = np;
> > +
> > +	port->base = devm_platform_ioremap_resource(platform, port->idx + 2);
> > +	if (IS_ERR(port->base))
> > +		return -ENODEV;
> > +
> > +	rmwl(0, PORT_APPCLK_EN, port + PORT_APPCLK);
> > +
> > +	rmwl(0, PORT_PERST_OFF, port->base + PORT_PERST);
> > +	gpiod_set_value(reset, 1);
> > +
> > +	ret = readl_relaxed_poll_timeout(port->base + PORT_STATUS, stat,
> > +					 stat & PORT_STATUS_READY, 100, 250000);
> > +	if (ret < 0) {
> > +		dev_err(pcie->dev, "port %pOF ready wait timeout\n", np);
> > +		return ret;
> > +	}
> > +
> > +	/* Flush writes and enable the link */
> > +	dma_wmb();
> 
> This is a DMA barrier but there's no DMA you need to order this against
> here. I think you can just drop it.

Indeed, this is all MMIO based, and doesn't refer to anything in
memory. Barrier gone.

Thanks,

	M.
Hector Martin Sept. 17, 2021, 10:42 a.m. UTC | #3
On 17/09/2021 18.20, Marc Zyngier wrote:
> On Mon, 13 Sep 2021 21:48:47 +0100,
>> On Mon, Sep 13, 2021, at 20:25, Marc Zyngier wrote:
>>> +static inline void rmwl(u32 clr, u32 set, void __iomem *addr)
>>> +{
>>> +	writel_relaxed((readl_relaxed(addr) & ~clr) | set, addr);
>>> +}
>>
>> This helper is a bit strange, especially since it's always only used
>> with either clr != 0 or set != 0 but never (clr = 0 and set = 0) afaict.
>> Maybe create two instead for setting and clearing bits?
> 
> That's indeed nicer, and it makes the code more readable.

This seems to be a pattern in Corellium code; the cpufreq code is the 
same and I honestly found it quite hard to read when used for simple set 
or clear operations. I find set32/clear32 style helpers much more 
readable, so it's probably a good idea to make this change any time we 
upstream stuff derived from their tree.
diff mbox series

Patch

diff --git a/MAINTAINERS b/MAINTAINERS
index 813a847e2d64..9905cc48fed9 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1280,6 +1280,13 @@  S:	Maintained
 F:	Documentation/devicetree/bindings/iommu/apple,dart.yaml
 F:	drivers/iommu/apple-dart.c
 
+APPLE PCIE CONTROLLER DRIVER
+M:	Alyssa Rosenzweig <alyssa@rosenzweig.io>
+M:	Marc Zyngier <maz@kernel.org>
+L:	linux-pci@vger.kernel.org
+S:	Maintained
+F:	drivers/pci/controller/pcie-apple.c
+
 APPLE SMC DRIVER
 M:	Henrik Rydberg <rydberg@bitmath.org>
 L:	linux-hwmon@vger.kernel.org
diff --git a/drivers/pci/controller/Kconfig b/drivers/pci/controller/Kconfig
index 326f7d13024f..814833a8120d 100644
--- a/drivers/pci/controller/Kconfig
+++ b/drivers/pci/controller/Kconfig
@@ -312,6 +312,18 @@  config PCIE_HISI_ERR
 	  Say Y here if you want error handling support
 	  for the PCIe controller's errors on HiSilicon HIP SoCs
 
+config PCIE_APPLE
+	tristate "Apple PCIe controller"
+	depends on ARCH_APPLE || COMPILE_TEST
+	depends on OF
+	depends on PCI_MSI_IRQ_DOMAIN
+	help
+	  Say Y here if you want to enable PCIe controller support on Apple
+	  system-on-chips, like the Apple M1. This is required for the USB
+	  type-A ports, Ethernet, Wi-Fi, and Bluetooth.
+
+	  If unsure, say Y if you have an Apple Silicon system.
+
 source "drivers/pci/controller/dwc/Kconfig"
 source "drivers/pci/controller/mobiveil/Kconfig"
 source "drivers/pci/controller/cadence/Kconfig"
diff --git a/drivers/pci/controller/Makefile b/drivers/pci/controller/Makefile
index aaf30b3dcc14..f9d40bad932c 100644
--- a/drivers/pci/controller/Makefile
+++ b/drivers/pci/controller/Makefile
@@ -37,6 +37,7 @@  obj-$(CONFIG_VMD) += vmd.o
 obj-$(CONFIG_PCIE_BRCMSTB) += pcie-brcmstb.o
 obj-$(CONFIG_PCI_LOONGSON) += pci-loongson.o
 obj-$(CONFIG_PCIE_HISI_ERR) += pcie-hisi-error.o
+obj-$(CONFIG_PCIE_APPLE) += pcie-apple.o
 # pcie-hisi.o quirks are needed even without CONFIG_PCIE_DW
 obj-y				+= dwc/
 obj-y				+= mobiveil/
diff --git a/drivers/pci/controller/pcie-apple.c b/drivers/pci/controller/pcie-apple.c
new file mode 100644
index 000000000000..f3c414950a10
--- /dev/null
+++ b/drivers/pci/controller/pcie-apple.c
@@ -0,0 +1,243 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * PCIe host bridge driver for Apple system-on-chips.
+ *
+ * The HW is ECAM compliant, so once the controller is initialized,
+ * the driver mostly deals MSI mapping and handling of per-port
+ * interrupts (INTx, management and error signals).
+ *
+ * Initialization requires enabling power and clocks, along with a
+ * number of register pokes.
+ *
+ * Copyright (C) 2021 Alyssa Rosenzweig <alyssa@rosenzweig.io>
+ * Copyright (C) 2021 Google LLC
+ * Copyright (C) 2021 Corellium LLC
+ * Copyright (C) 2021 Mark Kettenis <kettenis@openbsd.org>
+ *
+ * Author: Alyssa Rosenzweig <alyssa@rosenzweig.io>
+ * Author: Marc Zyngier <maz@kernel.org>
+ */
+
+#include <linux/gpio/consumer.h>
+#include <linux/kernel.h>
+#include <linux/iopoll.h>
+#include <linux/irqdomain.h>
+#include <linux/module.h>
+#include <linux/msi.h>
+#include <linux/of_irq.h>
+#include <linux/pci-ecam.h>
+
+#define CORE_RC_PHYIF_CTL		0x00024
+#define   CORE_RC_PHYIF_CTL_RUN		BIT(0)
+#define CORE_RC_PHYIF_STAT		0x00028
+#define   CORE_RC_PHYIF_STAT_REFCLK	BIT(4)
+#define CORE_RC_CTL			0x00050
+#define   CORE_RC_CTL_RUN		BIT(0)
+#define CORE_RC_STAT			0x00058
+#define   CORE_RC_STAT_READY		BIT(0)
+#define CORE_FABRIC_STAT		0x04000
+#define   CORE_FABRIC_STAT_MASK		0x001F001F
+#define CORE_LANE_CFG(port)		(0x84000 + 0x4000 * (port))
+#define   CORE_LANE_CFG_REFCLK0REQ	BIT(0)
+#define   CORE_LANE_CFG_REFCLK1		BIT(1)
+#define   CORE_LANE_CFG_REFCLK0ACK	BIT(2)
+#define   CORE_LANE_CFG_REFCLKEN	(BIT(9) | BIT(10))
+#define CORE_LANE_CTL(port)		(0x84004 + 0x4000 * (port))
+#define   CORE_LANE_CTL_CFGACC		BIT(15)
+
+#define PORT_LTSSMCTL			0x00080
+#define   PORT_LTSSMCTL_START		BIT(0)
+#define PORT_INTSTAT			0x00100
+#define   PORT_INT_TUNNEL_ERR		31
+#define   PORT_INT_CPL_TIMEOUT		23
+#define   PORT_INT_RID2SID_MAPERR	22
+#define   PORT_INT_CPL_ABORT		21
+#define   PORT_INT_MSI_BAD_DATA		19
+#define   PORT_INT_MSI_ERR		18
+#define   PORT_INT_REQADDR_GT32		17
+#define   PORT_INT_AF_TIMEOUT		15
+#define   PORT_INT_LINK_DOWN		14
+#define   PORT_INT_LINK_UP		12
+#define   PORT_INT_LINK_BWMGMT		11
+#define   PORT_INT_AER_MASK		(15 << 4)
+#define   PORT_INT_PORT_ERR		4
+#define   PORT_INT_INTx(i)		i
+#define   PORT_INT_INTx_MASK		15
+#define PORT_INTMSK			0x00104
+#define PORT_INTMSKSET			0x00108
+#define PORT_INTMSKCLR			0x0010c
+#define PORT_MSICFG			0x00124
+#define   PORT_MSICFG_EN		BIT(0)
+#define   PORT_MSICFG_L2MSINUM_SHIFT	4
+#define PORT_MSIBASE			0x00128
+#define   PORT_MSIBASE_1_SHIFT		16
+#define PORT_MSIADDR			0x00168
+#define PORT_LINKSTS			0x00208
+#define   PORT_LINKSTS_UP		BIT(0)
+#define   PORT_LINKSTS_BUSY		BIT(2)
+#define PORT_LINKCMDSTS			0x00210
+#define PORT_OUTS_NPREQS		0x00284
+#define   PORT_OUTS_NPREQS_REQ		BIT(24)
+#define   PORT_OUTS_NPREQS_CPL		BIT(16)
+#define PORT_RXWR_FIFO			0x00288
+#define   PORT_RXWR_FIFO_HDR		GENMASK(15, 10)
+#define   PORT_RXWR_FIFO_DATA		GENMASK(9, 0)
+#define PORT_RXRD_FIFO			0x0028C
+#define   PORT_RXRD_FIFO_REQ		GENMASK(6, 0)
+#define PORT_OUTS_CPLS			0x00290
+#define   PORT_OUTS_CPLS_SHRD		GENMASK(14, 8)
+#define   PORT_OUTS_CPLS_WAIT		GENMASK(6, 0)
+#define PORT_APPCLK			0x00800
+#define   PORT_APPCLK_EN		BIT(0)
+#define   PORT_APPCLK_CGDIS		BIT(8)
+#define PORT_STATUS			0x00804
+#define   PORT_STATUS_READY		BIT(0)
+#define PORT_REFCLK			0x00810
+#define   PORT_REFCLK_EN		BIT(0)
+#define   PORT_REFCLK_CGDIS		BIT(8)
+#define PORT_PERST			0x00814
+#define   PORT_PERST_OFF		BIT(0)
+#define PORT_RID2SID(i16)		(0x00828 + 4 * (i16))
+#define   PORT_RID2SID_VALID		BIT(31)
+#define   PORT_RID2SID_SID_SHIFT	16
+#define   PORT_RID2SID_BUS_SHIFT	8
+#define   PORT_RID2SID_DEV_SHIFT	3
+#define   PORT_RID2SID_FUNC_SHIFT	0
+#define PORT_OUTS_PREQS_HDR		0x00980
+#define   PORT_OUTS_PREQS_HDR_MASK	GENMASK(9, 0)
+#define PORT_OUTS_PREQS_DATA		0x00984
+#define   PORT_OUTS_PREQS_DATA_MASK	GENMASK(15, 0)
+#define PORT_TUNCTRL			0x00988
+#define   PORT_TUNCTRL_PERST_ON		BIT(0)
+#define   PORT_TUNCTRL_PERST_ACK_REQ	BIT(1)
+#define PORT_TUNSTAT			0x0098c
+#define   PORT_TUNSTAT_PERST_ON		BIT(0)
+#define   PORT_TUNSTAT_PERST_ACK_PEND	BIT(1)
+#define PORT_PREFMEM_ENABLE		0x00994
+
+struct apple_pcie {
+	struct device		*dev;
+	void __iomem            *base;
+};
+
+struct apple_pcie_port {
+	struct apple_pcie	*pcie;
+	struct device_node	*np;
+	void __iomem		*base;
+	int			idx;
+};
+
+static inline void rmwl(u32 clr, u32 set, void __iomem *addr)
+{
+	writel_relaxed((readl_relaxed(addr) & ~clr) | set, addr);
+}
+
+static int apple_pcie_setup_port(struct apple_pcie *pcie,
+				 struct device_node *np)
+{
+	struct platform_device *platform = to_platform_device(pcie->dev);
+	struct apple_pcie_port *port;
+	struct gpio_desc *reset;
+	u32 stat, idx;
+	int ret;
+
+	reset = gpiod_get_from_of_node(np, "reset-gpios", 0,
+				       GPIOD_OUT_LOW, "#PERST");
+	if (IS_ERR(reset))
+		return PTR_ERR(reset);
+
+	port = devm_kzalloc(pcie->dev, sizeof(*port), GFP_KERNEL);
+	if (!port)
+		return -ENOMEM;
+
+	ret = of_property_read_u32_index(np, "reg", 0, &idx);
+	if (ret)
+		return ret;
+
+	/* Use the first reg entry to work out the port index */
+	port->idx = idx >> 11;
+	port->pcie = pcie;
+	port->np = np;
+
+	port->base = devm_platform_ioremap_resource(platform, port->idx + 2);
+	if (IS_ERR(port->base))
+		return -ENODEV;
+
+	rmwl(0, PORT_APPCLK_EN, port + PORT_APPCLK);
+
+	rmwl(0, PORT_PERST_OFF, port->base + PORT_PERST);
+	gpiod_set_value(reset, 1);
+
+	ret = readl_relaxed_poll_timeout(port->base + PORT_STATUS, stat,
+					 stat & PORT_STATUS_READY, 100, 250000);
+	if (ret < 0) {
+		dev_err(pcie->dev, "port %pOF ready wait timeout\n", np);
+		return ret;
+	}
+
+	/* Flush writes and enable the link */
+	dma_wmb();
+
+	writel_relaxed(PORT_LTSSMCTL_START, port->base + PORT_LTSSMCTL);
+
+	return 0;
+}
+
+static int apple_pcie_init(struct pci_config_window *cfg)
+{
+	struct device *dev = cfg->parent;
+	struct platform_device *platform = to_platform_device(dev);
+	struct device_node *of_port;
+	struct apple_pcie *pcie;
+	int ret;
+
+	pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL);
+	if (!pcie)
+		return -ENOMEM;
+
+	pcie->dev = dev;
+
+	mutex_init(&pcie->lock);
+
+	pcie->base = devm_platform_ioremap_resource(platform, 1);
+
+	if (IS_ERR(pcie->base))
+		return -ENODEV;
+
+	for_each_child_of_node(dev->of_node, of_port) {
+		ret = apple_pcie_setup_port(pcie, of_port);
+		if (ret) {
+			dev_err(pcie->dev, "Port %pOF setup fail: %d\n", of_port, ret);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static const struct pci_ecam_ops apple_pcie_cfg_ecam_ops = {
+	.init		= apple_pcie_init,
+	.pci_ops	= {
+		.map_bus	= pci_ecam_map_bus,
+		.read		= pci_generic_config_read,
+		.write		= pci_generic_config_write,
+	}
+};
+
+static const struct of_device_id apple_pcie_of_match[] = {
+	{ .compatible = "apple,pcie", .data = &apple_pcie_cfg_ecam_ops },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, apple_pcie_of_match);
+
+static struct platform_driver apple_pcie_driver = {
+	.probe	= pci_host_common_probe,
+	.driver	= {
+		.name			= "pcie-apple",
+		.of_match_table		= apple_pcie_of_match,
+		.suppress_bind_attrs	= true,
+	},
+};
+module_platform_driver(apple_pcie_driver);
+
+MODULE_LICENSE("GPL v2");