[PATCH v3] PCI: Xilinx-NWL-PCIe: Added support for Xilinx NWL PCIe Host Controller

Marc Zyngier marc.zyngier at arm.com
Tue Oct 6 09:13:04 PDT 2015


Hi Bharat,

On 06/10/15 16:44, Bharat Kumar Gogada wrote:
> Adding PCIe Root Port driver for Xilinx PCIe NWL bridge IP.
> 
> Signed-off-by: Bharat Kumar Gogada <bharatku at xilinx.com>
> Signed-off-by: Ravi Kiran Gummaluri <rgummal at xilinx.com>
> ---
> Added interrupt-map, interrupt-map-mask properties
> ---
>  .../devicetree/bindings/pci/xilinx-nwl-pcie.txt    |   56 ++
>  drivers/pci/host/Kconfig                           |    9 +
>  drivers/pci/host/Makefile                          |    1 +
>  drivers/pci/host/pcie-xilinx-nwl.c                 | 1029 ++++++++++++++++++++
>  4 files changed, 1095 insertions(+), 0 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/pci/xilinx-nwl-pcie.txt
>  create mode 100644 drivers/pci/host/pcie-xilinx-nwl.c
> 
> diff --git a/Documentation/devicetree/bindings/pci/xilinx-nwl-pcie.txt b/Documentation/devicetree/bindings/pci/xilinx-nwl-pcie.txt
> new file mode 100644
> index 0000000..81006ab
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/pci/xilinx-nwl-pcie.txt
> @@ -0,0 +1,56 @@
> +* Xilinx NWL PCIe Root Port Bridge DT description
> +
> +Required properties:
> +- compatible: Should contain "xlnx,nwl-pcie-2.11"
> +- #address-cells: Address representation for root ports, set to <3>
> +- #size-cells: Size representation for root ports, set to <2>
> +- #interrupt-cells: specifies the number of cells needed to encode an
> +	interrupt source. The value must be 1.
> +- reg: Should contain Bridge, PCIe Controller registers location,
> +	configuration sapce, and length
> +- reg-names: Must include the following entries:
> +	"breg": bridge registers
> +	"pcireg": PCIe controller registers
> +	"cfg": configuration space region
> +- device_type: must be "pci"
> +- interrupts: Should contain NWL PCIe interrupt
> +- interrupt-names: Must include the following entries:
> +	"misc": interrupt asserted when miscellaneous is recieved
> +	"intx": interrupt that is asserted when an legacy interrupt is received
> +	"msi_1, msi_0": interrupt asserted when msi is recieved
> +- interrupt-map-mask and interrupt-map: standard PCI properties to define the
> +	mapping of the PCI interface to interrupt numbers.
> +- ranges: ranges for the PCI memory regions (I/O space region is not
> +	supported by hardware)
> +	Please refer to the standard PCI bus binding document for a more
> +	detailed explanation
> +
> +Optional properties:
> +- xlnx,msi-fifo: To enable MSI FIFO mode
> +	- This feature can be used to queue multiple MSI interrupts
> +
> +Example:
> +++++++++
> +nwl_pcie: pcie at fd0e0000 {
> +	compatible = "xlnx,nwl-pcie-2.11";
> +	#address-cells = <3>;
> +	#size-cells = <2>;
> +	#interrupt-cells = <1>;
> +	device_type = "pci";
> +	interrupt-parent = <&gic>;
> +	interrupts = < 0 118 4
> +		       0 116 4
> +		       0 115 4		// MSI_1 [63...32]
> +		       0 114 4 >;	// MSI_0 [31...0]
> +	interrupt-names = "misc", "intx", "msi_1", "msi_0";
> +	interrupt-map-mask = <0x0 0x0 0x0 0x7>;
> +	interrupt-map = <0x0 0x0 0x0 0x1 &gic 0x0 116 0x4
> +			0x0 0x0 0x0 0x2 &gic 0x0 116 0x4
> +			0x0 0x0 0x0 0x3 &gic 0x0 116 0x4
> +			0x0 0x0 0x0 0x4 &gic 0x0 116 0x4>;
> +	reg = <0x0 0xfd0e0000 0x1000
> +	       0x0 0xfd480000 0x1000
> +	       0x0 0xE0000000 0x1000000>;
> +	reg-names = "breg", "pcireg", "cfg";
> +	ranges = <0x02000000 0x00000000 0xE1000000 0x00000000 0xE1000000 0 0x0F000000>;
> +};

Please move this to a separate patch. This is big enough, and hard
enough to review.

> diff --git a/drivers/pci/host/Kconfig b/drivers/pci/host/Kconfig
> index c132bdd..7f5f35e 100644
> --- a/drivers/pci/host/Kconfig
> +++ b/drivers/pci/host/Kconfig
> @@ -15,6 +15,15 @@ config PCI_MVEBU
> 	depends on ARCH_MVEBU || ARCH_DOVE
> 	depends on OF
> 
> +config PCIE_XILINX_NWL
> +	bool "NWL PCIe Core && PCI_MSI"
> +	depends on ARCH_ZYNQMP
> +	help
> +	 Say 'Y' here if you want kernel to support for Xilinx
> +	 NWL PCIe controller.The controller can act as Root Port
> +	 or End Point.The current option selection will only

Add a space after the dot.

> +	 support root port enabling.
> +
>  config PCIE_DW
> 	bool
> 
> diff --git a/drivers/pci/host/Makefile b/drivers/pci/host/Makefile
> index 140d66f..6a56df7 100644
> --- a/drivers/pci/host/Makefile
> +++ b/drivers/pci/host/Makefile
> @@ -10,6 +10,7 @@ obj-$(CONFIG_PCI_HOST_GENERIC) += pci-host-generic.o
>  obj-$(CONFIG_PCIE_SPEAR13XX) += pcie-spear13xx.o
>  obj-$(CONFIG_PCI_KEYSTONE) += pci-keystone-dw.o pci-keystone.o
>  obj-$(CONFIG_PCIE_XILINX) += pcie-xilinx.o
> +obj-$(CONFIG_PCIE_XILINX_NWL) += pcie-xilinx-nwl.o
>  obj-$(CONFIG_PCI_XGENE) += pci-xgene.o
>  obj-$(CONFIG_PCI_XGENE_MSI) += pci-xgene-msi.o
>  obj-$(CONFIG_PCI_LAYERSCAPE) += pci-layerscape.o
> diff --git a/drivers/pci/host/pcie-xilinx-nwl.c b/drivers/pci/host/pcie-xilinx-nwl.c
> new file mode 100644
> index 0000000..ff25ec1
> --- /dev/null
> +++ b/drivers/pci/host/pcie-xilinx-nwl.c
> @@ -0,0 +1,1029 @@
> +/*
> + * PCIe host controller driver for NWL PCIe Bridge
> + * Based on pci-xilinx.c, pci-tegra.c
> + *
> + * (C) Copyright 2014 - 2015, Xilinx, Inc.
> + *
> + * This program is free software: you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation, either version 2 of the License, or
> + * (at your option) any later version.
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/interrupt.h>
> +#include <linux/irq.h>
> +#include <linux/irqdomain.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/msi.h>
> +#include <linux/of_address.h>
> +#include <linux/of_pci.h>
> +#include <linux/of_platform.h>
> +#include <linux/of_irq.h>
> +#include <linux/pci.h>
> +#include <linux/platform_device.h>
> +
> +/* Bridge core config registers */
> +#define BRCFG_PCIE_RX0			0x00000000
> +#define BRCFG_PCIE_RX1			0x00000004
> +#define BRCFG_AXI_MASTER		0x00000008
> +#define BRCFG_PCIE_TX			0x0000000C
> +#define BRCFG_INTERRUPT			0x00000010
> +#define BRCFG_RAM_DISABLE0		0x00000014
> +#define BRCFG_RAM_DISABLE1		0x00000018
> +#define BRCFG_PCIE_RELAXED_ORDER	0x0000001C
> +#define BRCFG_PCIE_RX_MSG_FILTER	0x00000020
> +
> +/* Attribute registers */
> +#define NWL_ATTRIB_100			0x00000190
> +
> +/* Egress - Bridge translation registers */
> +#define E_BREG_CAPABILITIES		0x00000200
> +#define E_BREG_STATUS			0x00000204
> +#define E_BREG_CONTROL			0x00000208
> +#define E_BREG_BASE_LO			0x00000210
> +#define E_BREG_BASE_HI			0x00000214
> +#define E_ECAM_CAPABILITIES		0x00000220
> +#define E_ECAM_STATUS			0x00000224
> +#define E_ECAM_CONTROL			0x00000228
> +#define E_ECAM_BASE_LO			0x00000230
> +#define E_ECAM_BASE_HI			0x00000234
> +
> +/* Ingress - address translations */
> +#define I_MSII_CAPABILITIES		0x00000300
> +#define I_MSII_CONTROL			0x00000308
> +#define I_MSII_BASE_LO			0x00000310
> +#define I_MSII_BASE_HI			0x00000314
> +
> +#define I_ISUB_CONTROL			0x000003E8
> +#define SET_ISUB_CONTROL		BIT(0)
> +/* Rxed msg fifo  - Interrupt status registers */
> +#define MSGF_MISC_STATUS		0x00000400
> +#define MSGF_MISC_MASK			0x00000404
> +#define MSGF_LEG_STATUS			0x00000420
> +#define MSGF_LEG_MASK			0x00000424
> +#define MSGF_MSI_STATUS_LO		0x00000440
> +#define MSGF_MSI_STATUS_HI		0x00000444
> +#define MSGF_MSI_MASK_LO		0x00000448
> +#define MSGF_MSI_MASK_HI		0x0000044C
> +#define MSGF_RX_FIFO_POP		0x00000484
> +#define MSGF_RX_FIFO_TYPE		0x00000488
> +#define MSGF_RX_FIFO_ADDRLO		0x00000490
> +#define MSGF_RX_FIFO_ADDRHI		0x00000494
> +#define MSGF_RX_FIFO_DATA		0x00000498
> +
> +/* Msg filter mask bits */
> +#define CFG_ENABLE_PM_MSG_FWD		BIT(1)
> +#define CFG_ENABLE_INT_MSG_FWD		BIT(2)
> +#define CFG_ENABLE_ERR_MSG_FWD		BIT(3)
> +#define CFG_ENABLE_SLT_MSG_FWD		BIT(5)
> +#define CFG_ENABLE_VEN_MSG_FWD		BIT(7)
> +#define CFG_ENABLE_OTH_MSG_FWD		BIT(13)
> +#define CFG_ENABLE_VEN_MSG_EN		BIT(14)
> +#define CFG_ENABLE_VEN_MSG_VEN_INV	BIT(15)
> +#define CFG_ENABLE_VEN_MSG_VEN_ID	GENMASK(31, 16)
> +#define CFG_ENABLE_MSG_FILTER_MASK	(CFG_ENABLE_PM_MSG_FWD | \
> +					CFG_ENABLE_INT_MSG_FWD | \
> +					CFG_ENABLE_ERR_MSG_FWD | \
> +					CFG_ENABLE_SLT_MSG_FWD | \
> +					CFG_ENABLE_VEN_MSG_FWD | \
> +					CFG_ENABLE_OTH_MSG_FWD | \
> +					CFG_ENABLE_VEN_MSG_EN | \
> +					CFG_ENABLE_VEN_MSG_VEN_INV | \
> +					CFG_ENABLE_VEN_MSG_VEN_ID)
> +
> +/* Misc interrupt status mask bits */
> +#define MSGF_MISC_SR_RXMSG_AVAIL	BIT(0)
> +#define MSGF_MISC_SR_RXMSG_OVER		BIT(1)
> +#define MSGF_MISC_SR_SLAVE_ERR		BIT(4)
> +#define MSGF_MISC_SR_MASTER_ERR		BIT(5)
> +#define MSGF_MISC_SR_I_ADDR_ERR		BIT(6)
> +#define MSGF_MISC_SR_E_ADDR_ERR		BIT(7)
> +
> +#define MSGF_MISC_SR_PCIE_CORE		GENMASK(18, 16)
> +#define MSGF_MISC_SR_PCIE_CORE_ERR	GENMASK(31, 20)
> +
> +#define MSGF_MISC_SR_MASKALL		(MSGF_MISC_SR_RXMSG_AVAIL | \
> +					MSGF_MISC_SR_RXMSG_OVER | \
> +					MSGF_MISC_SR_SLAVE_ERR | \
> +					MSGF_MISC_SR_MASTER_ERR | \
> +					MSGF_MISC_SR_I_ADDR_ERR | \
> +					MSGF_MISC_SR_E_ADDR_ERR | \
> +					MSGF_MISC_SR_PCIE_CORE | \
> +					MSGF_MISC_SR_PCIE_CORE_ERR)
> +
> +/* Message rx fifo type mask bits */
> +#define MSGF_RX_FIFO_TYPE_MSI	(1)
> +#define MSGF_RX_FIFO_TYPE_TYPE	GENMASK(1, 0)
> +
> +/* Legacy interrupt status mask bits */
> +#define MSGF_LEG_SR_INTA		BIT(0)
> +#define MSGF_LEG_SR_INTB		BIT(1)
> +#define MSGF_LEG_SR_INTC		BIT(2)
> +#define MSGF_LEG_SR_INTD		BIT(3)
> +#define MSGF_LEG_SR_MASKALL		(MSGF_LEG_SR_INTA | MSGF_LEG_SR_INTB | \
> +					MSGF_LEG_SR_INTC | MSGF_LEG_SR_INTD)
> +
> +/* MSI interrupt status mask bits */
> +#define MSGF_MSI_SR_LO_MASK		BIT(0)
> +#define MSGF_MSI_SR_HI_MASK		BIT(0)
> +
> +#define MSII_PRESENT			BIT(0)
> +#define MSII_ENABLE			BIT(0)
> +#define MSII_STATUS_ENABLE		BIT(15)
> +
> +/* Bridge config interrupt mask */
> +#define BRCFG_INTERRUPT_MASK		BIT(0)
> +#define BREG_PRESENT			BIT(0)
> +#define BREG_ENABLE			BIT(0)
> +#define BREG_ENABLE_FORCE		BIT(1)
> +
> +/* E_ECAM status mask bits */
> +#define E_ECAM_PRESENT			BIT(0)
> +#define E_ECAM_SR_WR_PEND		BIT(16)
> +#define E_ECAM_SR_RD_PEND		BIT(0)
> +#define E_ECAM_SR_MASKALL		(E_ECAM_SR_WR_PEND | E_ECAM_SR_RD_PEND)
> +#define E_ECAM_CR_ENABLE		BIT(0)
> +#define E_ECAM_SIZE_LOC			GENMASK(20, 16)
> +#define E_ECAM_SIZE_SHIFT		16
> +#define ECAM_BUS_LOC_SHIFT		20
> +#define ECAM_DEV_LOC_SHIFT		12
> +#define NWL_ECAM_VALUE_DEFAULT		12
> +#define NWL_ECAM_SIZE_MIN		4096
> +
> +#define ATTR_UPSTREAM_FACING		BIT(6)
> +#define CFG_DMA_REG_BAR			GENMASK(2, 0)
> +
> +/* msgf_rx_fifo_pop bits */
> +#define MSGF_RX_FIFO_POP_POP	BIT(0)
> +
> +#define INT_PCI_MSI_NR			(2 * 32)
> +
> +/* Readin the PS_LINKUP */
> +#define PS_LINKUP_OFFSET			0x00000238
> +#define PCIE_PHY_LINKUP_BIT			BIT(0)
> +#define PHY_RDY_LINKUP_BIT			BIT(1)
> +#define PCIE_USER_LINKUP			0
> +#define PHY_RDY_LINKUP				1
> +#define LINKUP_ITER_CHECK			5
> +
> +/* PCIE Message Request */
> +#define TX_PCIE_MSG				0x00000620
> +#define TX_PCIE_MSG_CNTL			0x00000004
> +#define TX_PCIE_MSG_SPEC_LO			0x00000008
> +#define TX_PCIE_MSG_SPEC_HI			0x0000000C
> +#define TX_PCIE_MSG_DATA			0x00000010
> +
> +#define MSG_BUSY_BIT				BIT(8)
> +#define MSG_EXECUTE_BIT				BIT(0)
> +#define MSG_DONE_BIT				BIT(16)
> +#define MSG_DONE_STATUS_BIT			(BIT(25) | BIT(24))
> +#define RANDOM_DIGIT				0x11223344
> +#define PATTRN_SSLP_TLP				0x01005074
> +
> +#define EXP_CAP_BASE				0x60
> +
> +/* SSPL ERROR */
> +#define SLVERR					0x02
> +#define DECERR					0x03
> +
> +struct nwl_msi {			/* struct nwl_msi - MSI information */
> +	struct msi_controller chip;	/* chip: MSI controller */

We're moving away from msi_controller altogether, as the kernel now has
all the necessary infrastructure to do this properly.

Please convert this driver to msi domains (see
drivers/pci/host/pci-xgene-msi.c or the gic-v2m driver as examples of
how this is being done).

> +	DECLARE_BITMAP(used, INT_PCI_MSI_NR);	/* used: Declare Bitmap
> +						for MSI	*/
> +	struct irq_domain *domain;	/* domain: IRQ domain pointer */
> +	unsigned long pages;		/* pages: MSI pages */
> +	struct mutex lock;		/* lock: mutex lock */
> +	int irq_msi0;			/* irq_msi0: msi0 interrupt number */
> +	int irq_msi1;			/* irq_msi1: msi1 interrupt number */
> +};

[...]

> +static irqreturn_t nwl_pcie_misc_handler(int irq, void *data)
> +{
> +	struct nwl_pcie *pcie = (struct nwl_pcie *)data;
> +	u32 misc_stat;
> +
> +	/* Checking for misc interrupts */
> +	misc_stat = nwl_bridge_readl(pcie, MSGF_MISC_STATUS) &
> +				     MSGF_MISC_SR_MASKALL;
> +	if (!misc_stat)
> +		return IRQ_NONE;
> +
> +	if (misc_stat & MSGF_MISC_SR_RXMSG_OVER)
> +		dev_err(pcie->dev, "Received Message FIFO Overflow\n");
> +
> +	if (misc_stat & MSGF_MISC_SR_SLAVE_ERR)
> +		dev_err(pcie->dev, "Slave error\n");
> +
> +	if (misc_stat & MSGF_MISC_SR_MASTER_ERR)
> +		dev_err(pcie->dev, "Master error\n");
> +
> +	if (misc_stat & MSGF_MISC_SR_I_ADDR_ERR)
> +		dev_err(pcie->dev,
> +			"In Misc Ingress address translation error\n");
> +
> +	if (misc_stat & MSGF_MISC_SR_E_ADDR_ERR)
> +		dev_err(pcie->dev,
> +			"In Misc Egress address translation error\n");
> +
> +	if (misc_stat & MSGF_MISC_SR_PCIE_CORE_ERR)
> +		dev_err(pcie->dev, "PCIe Core error\n");
> +
> +	if (pcie->enable_msi_fifo) {
> +		if (misc_stat & MSGF_MISC_SR_RXMSG_AVAIL) {
> +			u32 msg_type = nwl_bridge_readl(pcie,
> +							MSGF_RX_FIFO_TYPE) &
> +							MSGF_RX_FIFO_TYPE_TYPE;
> +
> +			if (msg_type == MSGF_RX_FIFO_TYPE_MSI) {
> +				u32 irq_msi;
> +				struct nwl_msi *msi = &pcie->msi;
> +				u32 msi_data = nwl_bridge_readl(pcie,
> +							MSGF_RX_FIFO_DATA);
> +				/* Let all ready be completed before write */
> +				rmb();
> +				/* POP the FIFO */
> +				nwl_bridge_writel(pcie, MSGF_RX_FIFO_POP_POP,
> +						  MSGF_RX_FIFO_POP);
> +
> +				/* Handle the msi virtual interrupt */
> +				irq_msi = irq_find_mapping(msi->domain,
> +							   msi_data);
> +
> +				if (irq_msi) {
> +					if (test_bit(msi_data, msi->used))
> +						generic_handle_irq(irq_msi);
> +					else
> +						dev_info(pcie->dev,
> +							 "unhandled MSI %d\n",
> +							 irq_msi);

No way. This implements a chained irqchip, not a normal IRQ handler. You
can't just reenter the core code like this.

Please convert this to a full chained irqchip.

> +				} else {
> +					dev_info(pcie->dev, "unexpected MSI\n");
> +				}
> +			}
> +		}
> +	}
> +	/* Clear misc interrupt status */
> +	nwl_bridge_writel(pcie, misc_stat, MSGF_MISC_STATUS);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t nwl_pcie_leg_handler(int irq, void *data)
> +{
> +	struct nwl_pcie *pcie = (struct nwl_pcie *)data;
> +	u32 leg_stat;
> +
> +	/* Checking for legacy interrupts */
> +	leg_stat = nwl_bridge_readl(pcie, MSGF_LEG_STATUS) &
> +				MSGF_LEG_SR_MASKALL;
> +	if (!leg_stat)
> +		return IRQ_NONE;
> +
> +	if (leg_stat & MSGF_LEG_SR_INTA)
> +		dev_dbg(pcie->dev, "legacy interruptA\n");
> +
> +	if (leg_stat & MSGF_LEG_SR_INTB)
> +		dev_dbg(pcie->dev, "legacy interruptB\n");
> +
> +	if (leg_stat & MSGF_LEG_SR_INTC)
> +		dev_dbg(pcie->dev, "legacy interruptC\n");
> +
> +	if (leg_stat & MSGF_LEG_SR_INTD)
> +		dev_dbg(pcie->dev, "legacy interruptD\n");
> +
> +	return IRQ_HANDLED;

And that's it? How useful is that? How do you make sure the line has
been lowered (if I remember well, legacy interrupts are LEVEL).

> +}
> +
> +static void __nwl_pcie_msi_handler(struct nwl_pcie *pcie,
> +					unsigned long reg, u32 val)
> +{
> +	struct nwl_msi *msi = &pcie->msi;
> +	unsigned int offset, index;
> +	int irq_msi;
> +
> +	offset = find_first_bit(&reg, 32);
> +	index = offset;
> +
> +	/* Clear the interrupt */
> +	nwl_bridge_writel(pcie, 1 << offset, val);
> +
> +	/* Handle the msi virtual interrupt */
> +	irq_msi = irq_find_mapping(msi->domain, index);
> +	if (irq_msi) {
> +		if (test_bit(index, msi->used))
> +			generic_handle_irq(irq_msi);
> +		else
> +			dev_info(pcie->dev, "unhandled MSI\n");
> +	} else {
> +		dev_info(pcie->dev, "unexpected MSI\n");
> +	}
> +}

I already commented on that, and on the need to using msi domains.

> +
> +static irqreturn_t nwl_pcie_msi_handler(int irq, void *data)
> +{
> +	struct nwl_pcie *pcie = data;
> +	unsigned long reg;
> +	int processed = 0;
> +
> +	reg = nwl_bridge_readl(pcie, MSGF_MSI_STATUS_LO);
> +	if (reg) {
> +		__nwl_pcie_msi_handler(pcie, reg, MSGF_MSI_STATUS_LO);
> +		processed++;
> +	}
> +
> +	reg = nwl_bridge_readl(pcie, MSGF_MSI_STATUS_HI);
> +	if (reg) {
> +		__nwl_pcie_msi_handler(pcie, reg, MSGF_MSI_STATUS_HI);
> +		processed++;
> +	}
> +
> +	return processed > 0 ? IRQ_HANDLED : IRQ_NONE;
> +}

I think you really need to document what all these handlers are...

> +
> +static int nwl_msi_alloc(struct nwl_msi *chip)
> +{
> +	int msi;
> +
> +	mutex_lock(&chip->lock);
> +
> +	msi = find_first_zero_bit(chip->used, INT_PCI_MSI_NR);
> +	if (msi < INT_PCI_MSI_NR)
> +		set_bit(msi, chip->used);
> +	else
> +		msi = -ENOSPC;
> +
> +	mutex_unlock(&chip->lock);
> +
> +	return msi;
> +}
> +
> +static void nwl_msi_free(struct nwl_msi *chip, unsigned long irq)
> +{
> +	struct device *dev = chip->chip.dev;
> +
> +	mutex_lock(&chip->lock);
> +
> +	if (!test_bit(irq, chip->used))
> +		dev_err(dev, "trying to free unused MSI#%lu\n", irq);
> +	else
> +		clear_bit(irq, chip->used);
> +
> +	mutex_unlock(&chip->lock);
> +}
> +
> +static int nwl_msi_setup_irq(struct msi_controller *chip, struct pci_dev *pdev,
> +			       struct msi_desc *desc)
> +{
> +	struct nwl_msi *msi = to_nwl_msi(chip);
> +	struct msi_msg msg;
> +	unsigned int irq;
> +	int hwirq;
> +
> +	/* currently we are not supporting MSIx */
> +	if (desc->msi_attrib.is_msix)
> +		return -ENOSPC;
> +
> +	hwirq = nwl_msi_alloc(msi);
> +	if (hwirq < 0)
> +		return hwirq;
> +
> +	irq = irq_create_mapping(msi->domain, hwirq);
> +	if (!irq)
> +		return -EINVAL;
> +
> +	irq_set_msi_desc(irq, desc);
> +
> +	msg.address_lo = virt_to_phys((void *)msi->pages);
> +	/* 32 bit address only */
> +	msg.address_hi = 0;
> +	msg.data = hwirq;
> +
> +	write_msi_msg(irq, &msg);
> +
> +	return 0;
> +}
> +
> +static void nwl_msi_teardown_irq(struct msi_controller *chip, unsigned int irq)
> +{
> +	struct nwl_msi *msi = to_nwl_msi(chip);
> +	struct irq_data *d = irq_get_irq_data(irq);
> +
> +	nwl_msi_free(msi, d->hwirq);
> +}
> +
> +static struct irq_chip nwl_msi_irq_chip = {
> +	.name = "nwl_pcie:msi",
> +	.irq_enable = unmask_msi_irq,
> +	.irq_disable = mask_msi_irq,
> +	.irq_mask = mask_msi_irq,
> +	.irq_unmask = unmask_msi_irq,
> +};

All that needs to go.

> +
> +static int nwl_msi_map(struct irq_domain *domain, unsigned int irq,
> +			 irq_hw_number_t hwirq)
> +{
> +	irq_set_chip_and_handler(irq, &nwl_msi_irq_chip, handle_simple_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 = nwl_msi_map,
> +};
> +
> +static int nwl_pcie_enable_msi(struct nwl_pcie *pcie, struct pci_bus *bus)
> +{
> +	struct platform_device *pdev = to_platform_device(pcie->dev);
> +	struct nwl_msi *msi = &pcie->msi;
> +	unsigned long base;
> +	int ret;
> +
> +	mutex_init(&msi->lock);
> +
> +	/* Assign msi chip hooks */
> +	msi->chip.dev = pcie->dev;
> +	msi->chip.setup_irq = nwl_msi_setup_irq;
> +	msi->chip.teardown_irq = nwl_msi_teardown_irq;
> +
> +	bus->msi = &msi->chip;
> +	msi->domain = irq_domain_add_linear(pcie->dev->of_node, INT_PCI_MSI_NR,
> +					    &msi_domain_ops, &msi->chip);
> +	if (!msi->domain) {
> +		dev_err(&pdev->dev, "failed to create IRQ domain\n");
> +		return -ENOMEM;
> +	}
> +
> +	/* Check for msii_present bit */
> +	ret = nwl_bridge_readl(pcie, I_MSII_CAPABILITIES) & MSII_PRESENT;
> +	if (!ret) {
> +		dev_err(pcie->dev, "MSI not present\n");
> +		ret = -EIO;
> +		goto err;
> +	}
> +
> +	/* Enable MSII */
> +	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, I_MSII_CONTROL) |
> +			  MSII_ENABLE, I_MSII_CONTROL);
> +	if (!pcie->enable_msi_fifo)
> +		/* Enable MSII status */
> +		nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, I_MSII_CONTROL) |
> +				  MSII_STATUS_ENABLE, I_MSII_CONTROL);
> +
> +	/* setup AFI/FPCI range */
> +	msi->pages = __get_free_pages(GFP_KERNEL, 0);
> +	base = virt_to_phys((void *)msi->pages);
> +	nwl_bridge_writel(pcie, base, I_MSII_BASE_LO);
> +	nwl_bridge_writel(pcie, 0x0, I_MSII_BASE_HI);
> +
> +	/* Disable high range msi interrupts */
> +	nwl_bridge_writel(pcie, (u32)~MSGF_MSI_SR_HI_MASK, MSGF_MSI_MASK_HI);
> +
> +	/* Clear pending high range msi interrupts */
> +	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie,  MSGF_MSI_STATUS_HI) &
> +			  MSGF_MSI_SR_HI_MASK, MSGF_MSI_STATUS_HI);
> +	/* Get msi_1 IRQ number */
> +	msi->irq_msi1 = platform_get_irq_byname(pdev, "msi_1");
> +	if (msi->irq_msi1 < 0) {
> +		dev_err(&pdev->dev, "failed to get IRQ#%d\n", msi->irq_msi1);
> +		goto err;
> +	}
> +	/* Register msi handler */
> +	ret = devm_request_irq(pcie->dev, msi->irq_msi1, nwl_pcie_msi_handler,
> +			       0, nwl_msi_irq_chip.name, pcie);
> +	if (ret < 0) {
> +		dev_err(&pdev->dev, "failed to request IRQ#%d\n",
> +					msi->irq_msi1);
> +		goto err;
> +	}
> +
> +	/* Enable all high range msi interrupts */
> +	nwl_bridge_writel(pcie, MSGF_MSI_SR_HI_MASK, MSGF_MSI_MASK_HI);
> +
> +	/* Disable low range msi interrupts */
> +	nwl_bridge_writel(pcie, (u32)~MSGF_MSI_SR_LO_MASK, MSGF_MSI_MASK_LO);
> +
> +	/* Clear pending low range msi interrupts */
> +	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, MSGF_MSI_STATUS_LO) &
> +			  MSGF_MSI_SR_LO_MASK, MSGF_MSI_STATUS_LO);
> +	/* Get msi_0 IRQ number */
> +	msi->irq_msi0 = platform_get_irq_byname(pdev, "msi_0");
> +	if (msi->irq_msi0 < 0) {
> +		dev_err(&pdev->dev, "failed to get IRQ#%d\n", msi->irq_msi0);
> +		goto err;
> +	}
> +	/* Register msi handler */
> +	ret = devm_request_irq(pcie->dev, msi->irq_msi0, nwl_pcie_msi_handler,
> +			       0, nwl_msi_irq_chip.name, pcie);
> +	if (ret < 0) {
> +		dev_err(&pdev->dev, "failed to request IRQ#%d\n",
> +					msi->irq_msi0);
> +		goto err;
> +	}
> +	/* Enable all low range msi interrupts */
> +	nwl_bridge_writel(pcie, MSGF_MSI_SR_LO_MASK, MSGF_MSI_MASK_LO);
> +
> +	return 0;
> +err:
> +	irq_domain_remove(msi->domain);
> +	return ret;
> +}
> +
> +static int nwl_pcie_bridge_init(struct nwl_pcie *pcie)
> +{
> +	struct platform_device *pdev = to_platform_device(pcie->dev);
> +	u32 breg_val, ecam_val, first_busno = 0;
> +	int err;
> +	int check_link_up = 0;
> +
> +	/* Check for BREG present bit */
> +	breg_val = nwl_bridge_readl(pcie, E_BREG_CAPABILITIES) & BREG_PRESENT;
> +	if (!breg_val) {
> +		dev_err(pcie->dev, "BREG is not present\n");
> +		return breg_val;
> +	}
> +	/* Write bridge_off to breg base */
> +	nwl_bridge_writel(pcie, (u32)(pcie->phys_breg_base),
> +			  E_BREG_BASE_LO);
> +
> +	/* Enable BREG */
> +	nwl_bridge_writel(pcie, ~BREG_ENABLE_FORCE & BREG_ENABLE,
> +			  E_BREG_CONTROL);
> +
> +	/* Disable DMA channel registers */
> +	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, BRCFG_PCIE_RX0) |
> +			  CFG_DMA_REG_BAR, BRCFG_PCIE_RX0);
> +
> +	/* Enable the bridge config interrupt */
> +	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, BRCFG_INTERRUPT) |
> +			  BRCFG_INTERRUPT_MASK, BRCFG_INTERRUPT);
> +	/* Enable Ingress subtractive decode translation */
> +	nwl_bridge_writel(pcie, SET_ISUB_CONTROL, I_ISUB_CONTROL);
> +
> +	/* Enable msg filtering details */
> +	nwl_bridge_writel(pcie, CFG_ENABLE_MSG_FILTER_MASK,
> +			  BRCFG_PCIE_RX_MSG_FILTER);
> +	do {
> +		err = nwl_pcie_link_up(pcie, PHY_RDY_LINKUP);
> +		if (err != 1) {
> +			check_link_up++;
> +			if (check_link_up > LINKUP_ITER_CHECK)
> +				return -ENODEV;
> +			mdelay(1000);
> +		}
> +	} while (!err);
> +
> +	/* Check for ECAM present bit */
> +	ecam_val = nwl_bridge_readl(pcie, E_ECAM_CAPABILITIES) & E_ECAM_PRESENT;
> +	if (!ecam_val) {
> +		dev_err(pcie->dev, "ECAM is not present\n");
> +		return ecam_val;
> +	}
> +
> +	/* Enable ECAM */
> +	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, E_ECAM_CONTROL) |
> +			  E_ECAM_CR_ENABLE, E_ECAM_CONTROL);
> +	/* Write ecam_value on ecam_control */
> +	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, E_ECAM_CONTROL) |
> +			  (pcie->ecam_value << E_ECAM_SIZE_SHIFT),
> +			  E_ECAM_CONTROL);
> +	/* Write phy_reg_base to ecam base */
> +	nwl_bridge_writel(pcie, (u32)pcie->phys_ecam_base, E_ECAM_BASE_LO);
> +
> +	/* Get bus range */
> +	ecam_val = nwl_bridge_readl(pcie, E_ECAM_CONTROL);
> +	pcie->last_busno = (ecam_val & E_ECAM_SIZE_LOC) >> E_ECAM_SIZE_SHIFT;
> +	/* Write primary, secondary and subordinate bus numbers */
> +	ecam_val = first_busno;
> +	ecam_val |= (first_busno + 1) << 8;
> +	ecam_val |= (pcie->last_busno << E_ECAM_SIZE_SHIFT);
> +	writel(ecam_val, (pcie->ecam_base + PCI_PRIMARY_BUS));
> +
> +	/* Check if PCIe link is up? */
> +	pcie->link_up = nwl_pcie_link_up(pcie, PCIE_USER_LINKUP);
> +	if (!pcie->link_up)
> +		dev_info(pcie->dev, "Link is DOWN\n");
> +	else
> +		dev_info(pcie->dev, "Link is UP\n");
> +
> +	/* Disable all misc interrupts */
> +	nwl_bridge_writel(pcie, (u32)~MSGF_MISC_SR_MASKALL, MSGF_MISC_MASK);
> +
> +	/* Clear pending misc interrupts */
> +	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, MSGF_MISC_STATUS) &
> +			  MSGF_MISC_SR_MASKALL, MSGF_MISC_STATUS);
> +
> +	/* Get misc IRQ number */
> +	pcie->irq_misc = platform_get_irq_byname(pdev, "misc");
> +	if (pcie->irq_misc < 0) {
> +		dev_err(&pdev->dev, "failed to get misc IRQ#%d\n",
> +			pcie->irq_misc);
> +		return pcie->irq_misc;
> +	}
> +	/* Register misc handler */
> +	err = devm_request_irq(pcie->dev, pcie->irq_misc,
> +			       nwl_pcie_misc_handler, IRQF_SHARED,
> +			       "nwl_pcie:misc", pcie);
> +	if (err) {
> +		dev_err(pcie->dev, "fail to register misc IRQ#%d\n",
> +			pcie->irq_misc);
> +		return err;
> +	}
> +	/* Enable all misc interrupts */
> +	nwl_bridge_writel(pcie, MSGF_MISC_SR_MASKALL, MSGF_MISC_MASK);
> +
> +	/* Disable all legacy interrupts */
> +	nwl_bridge_writel(pcie, (u32)~MSGF_LEG_SR_MASKALL, MSGF_LEG_MASK);
> +
> +	/* Clear pending legacy interrupts */
> +	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, MSGF_LEG_STATUS) &
> +			  MSGF_LEG_SR_MASKALL, MSGF_LEG_STATUS);
> +	/* Get intx IRQ number */
> +	pcie->irq_intx = platform_get_irq_byname(pdev, "intx");
> +	if (pcie->irq_intx < 0) {
> +		dev_err(&pdev->dev, "failed to get intx IRQ#%d\n",
> +			pcie->irq_intx);
> +		return pcie->irq_intx;
> +	}
> +
> +	/* Register intx handler */
> +	err = devm_request_irq(pcie->dev, pcie->irq_intx,
> +			       nwl_pcie_leg_handler, IRQF_SHARED,
> +			       "nwl_pcie:intx", pcie);
> +	if (err) {
> +		dev_err(pcie->dev, "fail to register intx IRQ#%d\n",
> +			pcie->irq_intx);
> +		return err;
> +	}
> +	/* Enable all legacy interrupts */
> +	nwl_bridge_writel(pcie, MSGF_LEG_SR_MASKALL, MSGF_LEG_MASK);
> +
> +	return 0;
> +}
> +
> +static int nwl_pcie_parse_dt(struct nwl_pcie *pcie,
> +					struct platform_device *pdev)
> +{
> +	struct device_node *node = pcie->dev->of_node;
> +	struct resource *res;
> +	const char *type;
> +
> +	/* Check for device type */
> +	type = of_get_property(node, "device_type", NULL);
> +	if (!type || strcmp(type, "pci")) {
> +		dev_err(pcie->dev, "invalid \"device_type\" %s\n", type);
> +		return -EINVAL;
> +	}

How can this fail?

> +
> +	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "breg");
> +	pcie->breg_base = devm_ioremap_resource(pcie->dev, res);
> +	if (IS_ERR(pcie->breg_base))
> +		return PTR_ERR(pcie->breg_base);
> +	pcie->phys_breg_base = res->start;
> +
> +	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "pcireg");
> +	pcie->pcireg_base = devm_ioremap_resource(pcie->dev, res);
> +	if (IS_ERR(pcie->pcireg_base))
> +		return PTR_ERR(pcie->pcireg_base);
> +	pcie->phys_pcie_reg_base = res->start;
> +
> +	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg");
> +	pcie->ecam_base = devm_ioremap_resource(pcie->dev, res);
> +	if (IS_ERR(pcie->ecam_base))
> +		return PTR_ERR(pcie->ecam_base);
> +	pcie->phys_ecam_base = res->start;
> +
> +	pcie->enable_msi_fifo = of_property_read_bool(node, "xlnx,msi-fifo");
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id nwl_pcie_of_match[] = {
> +	{ .compatible = "xlnx,nwl-pcie-2.11", },
> +	{}
> +};
> +
> +static int nwl_pcie_probe(struct platform_device *pdev)
> +{
> +	struct device_node *node = pdev->dev.of_node;
> +	struct nwl_pcie *pcie;
> +	struct pci_bus *bus;
> +	int err;
> +
> +	resource_size_t iobase = 0;
> +	LIST_HEAD(res);
> +
> +	pcie = devm_kzalloc(&pdev->dev, sizeof(*pcie), GFP_KERNEL);
> +	if (!pcie)
> +		return -ENOMEM;
> +
> +	pcie->ecam_value = NWL_ECAM_VALUE_DEFAULT;
> +
> +	pcie->dev = &pdev->dev;
> +
> +	err = nwl_pcie_parse_dt(pcie, pdev);
> +	if (err) {
> +		dev_err(pcie->dev, "Parsing DT failed\n");
> +		return err;
> +	}
> +	/* Bridge initialization */
> +	err = nwl_pcie_bridge_init(pcie);
> +	if (err) {
> +		dev_err(pcie->dev, "HW Initalization failed\n");
> +		return err;
> +	}
> +
> +	err = of_pci_get_host_bridge_resources(node, 0, 0xff, &res, &iobase);
> +	if (err) {
> +		pr_err("Getting bridge resources failed\n");
> +		return err;
> +	}
> +	bus = pci_create_root_bus(&pdev->dev, 0,
> +				  &nwl_pcie_ops, pcie, &res);
> +	if (!bus)
> +		return -ENOMEM;
> +
> +	/* Enable MSI */
> +	if (IS_ENABLED(CONFIG_PCI_MSI)) {
> +		err = nwl_pcie_enable_msi(pcie, bus);
> +		if (err < 0) {
> +			dev_err(&pdev->dev,
> +				"failed to enable MSI support: %d\n",
> +				err);
> +			return err;
> +		}
> +	}
> +	pci_scan_child_bus(bus);
> +	pci_assign_unassigned_bus_resources(bus);
> +	pci_bus_add_devices(bus);
> +	platform_set_drvdata(pdev, pcie);
> +
> +	return 0;
> +}
> +
> +static int nwl_pcie_remove(struct platform_device *pdev)
> +{
> +	platform_set_drvdata(pdev, NULL);
> +
> +	return 0;
> +}
> +
> +static struct platform_driver nwl_pcie_driver = {
> +	.driver = {
> +		.name = "nwl-pcie",
> +		.of_match_table = nwl_pcie_of_match,
> +	},
> +	.probe = nwl_pcie_probe,
> +	.remove = nwl_pcie_remove,
> +};
> +module_platform_driver(nwl_pcie_driver);
> +
> +MODULE_AUTHOR("Xilinx, Inc");
> +MODULE_DESCRIPTION("NWL PCIe driver");
> +MODULE_LICENSE("GPL");
> --
> 1.7.1

Overall, I think it would make sense to split the PCIe controller driver
and the MSI controller (in separate files as well).

Please keep me posted on the updates.

Thanks,

	M.
-- 
Jazz is not dead. It just smells funny...



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