[PATCH v7 3/3] PCI: xilinx-xdma: Add Xilinx XDMA Root Port driver

From: Thippeswamy Havalige
Date: Wed Aug 30 2023 - 15:16:41 EST


Add support for Xilinx XDMA Soft IP core as Root Port.

The Zynq UltraScale+ MPSoCs devices support XDMA soft IP module in
programmable logic.

The integrated XDMA soft IP block has integrated bridge function that
can act as PCIe Root Port.

Signed-off-by: Thippeswamy Havalige <thippeswamy.havalige@xxxxxxx>
Signed-off-by: Bharat Kumar Gogada <bharat.kumar.gogada@xxxxxxx>
---
changes in v7:
- Modify link-up check comments.
- Wrap few lines to 80 columns.
changes in v6:
- Replaced chained irq's with regular interrupts.
- Modified interrupt names.
- Aligned to 80 columns
changes in v5:
- Added detailed comments for link_up check.
- Modified upper case hex values to lower case.
changes in v4:
- Fixed unsigned integer to integer.
- Fixed return type to EINVAL.
changes in v3:
- Changed license to 2023.
- Added bitfield header to avoid implicit warning.
- Fixed indentation issue.
- Fixed code-style.
changes in v2:
- Remove unnecessary inclusion of headerfiles.
- Added a subset of interrupt error bits to common header files.
- Added pci_is_root_bus function.
- Removed kerneldoc comments of private function.
- Modified of_get_next_child API to of_get_child_by_name.
- Modified of_address_to_resource API to platform_get_resource.
- Modified return value.
---
drivers/pci/controller/Kconfig | 11 +
drivers/pci/controller/Makefile | 1 +
drivers/pci/controller/pcie-xilinx-common.h | 1 +
drivers/pci/controller/pcie-xilinx-dma-pl.c | 803 ++++++++++++++++++++++++++++
4 files changed, 816 insertions(+)
create mode 100644 drivers/pci/controller/pcie-xilinx-dma-pl.c

diff --git a/drivers/pci/controller/Kconfig b/drivers/pci/controller/Kconfig
index 0859be8..b9e8fb7 100644
--- a/drivers/pci/controller/Kconfig
+++ b/drivers/pci/controller/Kconfig
@@ -324,6 +324,17 @@ config PCIE_XILINX
Say 'Y' here if you want kernel to support the Xilinx AXI PCIe
Host Bridge driver.

+config PCIE_XILINX_DMA_PL
+ bool "Xilinx DMA PL PCIe host bridge support"
+ depends on ARCH_ZYNQMP || COMPILE_TEST
+ depends on PCI_MSI
+ select PCI_HOST_COMMON
+ help
+ Add support for the Xilinx PL DMA PCIe host bridge,
+ The controller is soft IP which can act as Root Port.
+ If you know your system provides Xilinx PCIe host controller
+ bridge DMA as soft IP say Y; if you are not sure, say N.
+
config PCIE_XILINX_NWL
bool "Xilinx NWL PCIe controller"
depends on ARCH_ZYNQMP || COMPILE_TEST
diff --git a/drivers/pci/controller/Makefile b/drivers/pci/controller/Makefile
index 37c8663..f2b19e6 100644
--- a/drivers/pci/controller/Makefile
+++ b/drivers/pci/controller/Makefile
@@ -17,6 +17,7 @@ obj-$(CONFIG_PCI_HOST_THUNDER_PEM) += pci-thunder-pem.o
obj-$(CONFIG_PCIE_XILINX) += pcie-xilinx.o
obj-$(CONFIG_PCIE_XILINX_NWL) += pcie-xilinx-nwl.o
obj-$(CONFIG_PCIE_XILINX_CPM) += pcie-xilinx-cpm.o
+obj-$(CONFIG_PCIE_XILINX_DMA_PL) += pcie-xilinx-dma-pl.o
obj-$(CONFIG_PCI_V3_SEMI) += pci-v3-semi.o
obj-$(CONFIG_PCI_XGENE) += pci-xgene.o
obj-$(CONFIG_PCI_XGENE_MSI) += pci-xgene-msi.o
diff --git a/drivers/pci/controller/pcie-xilinx-common.h b/drivers/pci/controller/pcie-xilinx-common.h
index e97d272..1832770 100644
--- a/drivers/pci/controller/pcie-xilinx-common.h
+++ b/drivers/pci/controller/pcie-xilinx-common.h
@@ -19,6 +19,7 @@
#define XILINX_PCIE_INTR_PME_TO_ACK_RCVD 15
#define XILINX_PCIE_INTR_INTX 16
#define XILINX_PCIE_INTR_PM_PME_RCVD 17
+#define XILINX_PCIE_INTR_MSI 17
#define XILINX_PCIE_INTR_SLV_UNSUPP 20
#define XILINX_PCIE_INTR_SLV_UNEXP 21
#define XILINX_PCIE_INTR_SLV_COMPL 22
diff --git a/drivers/pci/controller/pcie-xilinx-dma-pl.c b/drivers/pci/controller/pcie-xilinx-dma-pl.c
new file mode 100644
index 0000000..96639fe
--- /dev/null
+++ b/drivers/pci/controller/pcie-xilinx-dma-pl.c
@@ -0,0 +1,803 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * PCIe host controller driver for Xilinx XDMA PCIe Bridge
+ *
+ * Copyright (C) 2023 Xilinx, Inc. All rights reserved.
+ */
+#include <linux/bitfield.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 "../pci.h"
+#include "pcie-xilinx-common.h"
+
+/* Register definitions */
+#define XILINX_PCIE_DMA_REG_IDR 0x00000138
+#define XILINX_PCIE_DMA_REG_IMR 0x0000013c
+#define XILINX_PCIE_DMA_REG_PSCR 0x00000144
+#define XILINX_PCIE_DMA_REG_RPSC 0x00000148
+#define XILINX_PCIE_DMA_REG_MSIBASE1 0x0000014c
+#define XILINX_PCIE_DMA_REG_MSIBASE2 0x00000150
+#define XILINX_PCIE_DMA_REG_RPEFR 0x00000154
+#define XILINX_PCIE_DMA_REG_IDRN 0x00000160
+#define XILINX_PCIE_DMA_REG_IDRN_MASK 0x00000164
+#define XILINX_PCIE_DMA_REG_MSI_LOW 0x00000170
+#define XILINX_PCIE_DMA_REG_MSI_HI 0x00000174
+#define XILINX_PCIE_DMA_REG_MSI_LOW_MASK 0x00000178
+#define XILINX_PCIE_DMA_REG_MSI_HI_MASK 0x0000017c
+
+#define IMR(x) BIT(XILINX_PCIE_INTR_ ##x)
+
+#define XILINX_PCIE_INTR_IMR_ALL_MASK \
+ ( \
+ IMR(LINK_DOWN) | \
+ IMR(HOT_RESET) | \
+ IMR(CFG_TIMEOUT) | \
+ IMR(CORRECTABLE) | \
+ IMR(NONFATAL) | \
+ IMR(FATAL) | \
+ IMR(INTX) | \
+ IMR(MSI) | \
+ IMR(SLV_UNSUPP) | \
+ IMR(SLV_UNEXP) | \
+ IMR(SLV_COMPL) | \
+ IMR(SLV_ERRP) | \
+ IMR(SLV_CMPABT) | \
+ IMR(SLV_ILLBUR) | \
+ IMR(MST_DECERR) | \
+ IMR(MST_SLVERR) | \
+ )
+
+#define XILINX_PCIE_DMA_IMR_ALL_MASK 0x0ff30fe9
+#define XILINX_PCIE_DMA_IDR_ALL_MASK 0xffffffff
+#define XILINX_PCIE_DMA_IDRN_MASK GENMASK(19, 16)
+
+/* Root Port Error Register definitions */
+#define XILINX_PCIE_DMA_RPEFR_ERR_VALID BIT(18)
+#define XILINX_PCIE_DMA_RPEFR_REQ_ID GENMASK(15, 0)
+#define XILINX_PCIE_DMA_RPEFR_ALL_MASK 0xffffffff
+
+/* Root Port Interrupt Register definitions */
+#define XILINX_PCIE_DMA_IDRN_SHIFT 16
+
+/* Root Port Status/control Register definitions */
+#define XILINX_PCIE_DMA_REG_RPSC_BEN BIT(0)
+
+/* Phy Status/Control Register definitions */
+#define XILINX_PCIE_DMA_REG_PSCR_LNKUP BIT(11)
+
+/* Number of MSI IRQs */
+#define XILINX_NUM_MSI_IRQS 64
+
+struct xilinx_msi {
+ struct irq_domain *msi_domain;
+ unsigned long *bitmap;
+ struct irq_domain *dev_domain;
+ struct mutex lock; /* protect bitmap variable */
+ int irq_msi0;
+ int irq_msi1;
+};
+
+/**
+ * struct pl_dma_pcie - PCIe port information
+ * @dev: Device pointer
+ * @reg_base: IO Mapped Register Base
+ * @irq: Interrupt number
+ * @cfg: Holds mappings of config space window
+ * @phys_reg_base: Physical address of reg base
+ * @intx_domain: Legacy IRQ domain pointer
+ * @pldma_domain: PL DMA IRQ domain pointer
+ * @resources: Bus Resources
+ * @msi: MSI information
+ * @intx_irq: INTx error interrupt number
+ * @lock: Lock protecting shared register access
+ */
+struct pl_dma_pcie {
+ struct device *dev;
+ void __iomem *reg_base;
+ int irq;
+ struct pci_config_window *cfg;
+ phys_addr_t phys_reg_base;
+ struct irq_domain *intx_domain;
+ struct irq_domain *pldma_domain;
+ struct list_head resources;
+ struct xilinx_msi msi;
+ int intx_irq;
+ raw_spinlock_t lock;
+};
+
+static inline u32 pcie_read(struct pl_dma_pcie *port, u32 reg)
+{
+ return readl(port->reg_base + reg);
+}
+
+static inline void pcie_write(struct pl_dma_pcie *port, u32 val, u32 reg)
+{
+ writel(val, port->reg_base + reg);
+}
+
+static inline bool xilinx_pl_dma_pcie_link_up(struct pl_dma_pcie *port)
+{
+ return (pcie_read(port, XILINX_PCIE_DMA_REG_PSCR) &
+ XILINX_PCIE_DMA_REG_PSCR_LNKUP) ? true : false;
+}
+
+static void xilinx_pl_dma_pcie_clear_err_interrupts(struct pl_dma_pcie *port)
+{
+ unsigned long val = pcie_read(port, XILINX_PCIE_DMA_REG_RPEFR);
+
+ if (val & XILINX_PCIE_DMA_RPEFR_ERR_VALID) {
+ dev_dbg(port->dev, "Requester ID %lu\n",
+ val & XILINX_PCIE_DMA_RPEFR_REQ_ID);
+ pcie_write(port, XILINX_PCIE_DMA_RPEFR_ALL_MASK,
+ XILINX_PCIE_DMA_REG_RPEFR);
+ }
+}
+
+static bool xilinx_pl_dma_pcie_valid_device(struct pci_bus *bus,
+ unsigned int devfn)
+{
+ struct pl_dma_pcie *port = bus->sysdata;
+
+ if (!pci_is_root_bus(bus)) {
+ /* Checking whether the link is up is the last line of
+ * defense, and this check is inherently racy by definition.
+ * Sending a PIO request to a downstream device when the link is
+ * down causes an unrecoverable error, and a reset of the entire
+ * PCIe controller will be needed. We can reduce the likelihood
+ * of that unrecoverable error by checking whether the link is
+ * up, but we can't completely prevent it because the link may
+ * go down between the link-up check and the PIO request.
+ */
+ if (!xilinx_pl_dma_pcie_link_up(port))
+ return false;
+ } else if (devfn > 0)
+ /* Only one device down on each root port */
+ return false;
+
+ return true;
+}
+
+static void __iomem *xilinx_pl_dma_pcie_map_bus(struct pci_bus *bus,
+ unsigned int devfn, int where)
+{
+ struct pl_dma_pcie *port = bus->sysdata;
+
+ if (!xilinx_pl_dma_pcie_valid_device(bus, devfn))
+ return NULL;
+
+ return port->reg_base + PCIE_ECAM_OFFSET(bus->number, devfn, where);
+}
+
+/* PCIe operations */
+static struct pci_ecam_ops xilinx_pl_dma_pcie_ops = {
+ .pci_ops = {
+ .map_bus = xilinx_pl_dma_pcie_map_bus,
+ .read = pci_generic_config_read,
+ .write = pci_generic_config_write,
+ }
+};
+
+static void xilinx_pl_dma_pcie_enable_msi(struct pl_dma_pcie *port)
+{
+ phys_addr_t msi_addr = port->phys_reg_base;
+
+ pcie_write(port, upper_32_bits(msi_addr), XILINX_PCIE_DMA_REG_MSIBASE1);
+ pcie_write(port, lower_32_bits(msi_addr), XILINX_PCIE_DMA_REG_MSIBASE2);
+}
+
+static void xilinx_mask_intx_irq(struct irq_data *data)
+{
+ struct pl_dma_pcie *port = irq_data_get_irq_chip_data(data);
+ unsigned long flags;
+ u32 mask, val;
+
+ mask = BIT(data->hwirq + XILINX_PCIE_DMA_IDRN_SHIFT);
+ raw_spin_lock_irqsave(&port->lock, flags);
+ val = pcie_read(port, XILINX_PCIE_DMA_REG_IDRN_MASK);
+ pcie_write(port, (val & (~mask)), XILINX_PCIE_DMA_REG_IDRN_MASK);
+ raw_spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static void xilinx_unmask_intx_irq(struct irq_data *data)
+{
+ struct pl_dma_pcie *port = irq_data_get_irq_chip_data(data);
+ unsigned long flags;
+ u32 mask, val;
+
+ mask = BIT(data->hwirq + XILINX_PCIE_DMA_IDRN_SHIFT);
+ raw_spin_lock_irqsave(&port->lock, flags);
+ val = pcie_read(port, XILINX_PCIE_DMA_REG_IDRN_MASK);
+ pcie_write(port, (val | mask), XILINX_PCIE_DMA_REG_IDRN_MASK);
+ raw_spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static struct irq_chip xilinx_leg_irq_chip = {
+ .name = "pl_dma:INTx",
+ .irq_mask = xilinx_mask_intx_irq,
+ .irq_unmask = xilinx_unmask_intx_irq,
+};
+
+static int xilinx_pl_dma_pcie_intx_map(struct irq_domain *domain,
+ unsigned int irq, irq_hw_number_t hwirq)
+{
+ irq_set_chip_and_handler(irq, &xilinx_leg_irq_chip, handle_level_irq);
+ irq_set_chip_data(irq, domain->host_data);
+ irq_set_status_flags(irq, IRQ_LEVEL);
+
+ return 0;
+}
+
+/* INTx IRQ Domain operations */
+static const struct irq_domain_ops intx_domain_ops = {
+ .map = xilinx_pl_dma_pcie_intx_map,
+};
+
+static irqreturn_t xilinx_pl_dma_pcie_msi_handler_high(int irq, void *args)
+{
+ struct xilinx_msi *msi;
+ unsigned long status;
+ u32 bit, virq;
+ struct pl_dma_pcie *port = args;
+
+ msi = &port->msi;
+
+ while ((status = pcie_read(port, XILINX_PCIE_DMA_REG_MSI_HI)) != 0) {
+ for_each_set_bit(bit, &status, 32) {
+ pcie_write(port, 1 << bit, XILINX_PCIE_DMA_REG_MSI_HI);
+ bit = bit + 32;
+ virq = irq_find_mapping(msi->dev_domain, bit);
+ if (virq)
+ generic_handle_irq(virq);
+ }
+ }
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t xilinx_pl_dma_pcie_msi_handler_low(int irq, void *args)
+{
+ struct pl_dma_pcie *port = args;
+ struct xilinx_msi *msi;
+ unsigned long status;
+ u32 bit, virq;
+
+ msi = &port->msi;
+
+ while ((status = pcie_read(port, XILINX_PCIE_DMA_REG_MSI_LOW)) != 0) {
+ for_each_set_bit(bit, &status, 32) {
+ pcie_write(port, 1 << bit, XILINX_PCIE_DMA_REG_MSI_LOW);
+ virq = irq_find_mapping(msi->dev_domain, bit);
+ if (virq)
+ generic_handle_irq(virq);
+ }
+ }
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t xilinx_pl_dma_pcie_event_flow(int irq, void *args)
+{
+ struct pl_dma_pcie *port = args;
+ unsigned long val;
+ int i;
+
+ val = pcie_read(port, XILINX_PCIE_DMA_REG_IDR);
+ val &= pcie_read(port, XILINX_PCIE_DMA_REG_IMR);
+ for_each_set_bit(i, &val, 32)
+ generic_handle_domain_irq(port->pldma_domain, i);
+
+ pcie_write(port, val, XILINX_PCIE_DMA_REG_IDR);
+
+ return IRQ_HANDLED;
+}
+
+#define _IC(x, s) \
+ [XILINX_PCIE_INTR_ ## x] = { __stringify(x), s }
+
+static const struct {
+ const char *sym;
+ const char *str;
+} intr_cause[32] = {
+ _IC(LINK_DOWN, "Link Down"),
+ _IC(HOT_RESET, "Hot reset"),
+ _IC(CFG_TIMEOUT, "ECAM access timeout"),
+ _IC(CORRECTABLE, "Correctable error message"),
+ _IC(NONFATAL, "Non fatal error message"),
+ _IC(FATAL, "Fatal error message"),
+ _IC(SLV_UNSUPP, "Slave unsupported request"),
+ _IC(SLV_UNEXP, "Slave unexpected completion"),
+ _IC(SLV_COMPL, "Slave completion timeout"),
+ _IC(SLV_ERRP, "Slave Error Poison"),
+ _IC(SLV_CMPABT, "Slave Completer Abort"),
+ _IC(SLV_ILLBUR, "Slave Illegal Burst"),
+ _IC(MST_DECERR, "Master decode error"),
+ _IC(MST_SLVERR, "Master slave error"),
+};
+
+static irqreturn_t xilinx_pl_dma_pcie_intr_handler(int irq, void *dev_id)
+{
+ struct pl_dma_pcie *port = (struct pl_dma_pcie *)dev_id;
+ struct device *dev = port->dev;
+ struct irq_data *d;
+
+ d = irq_domain_get_irq_data(port->pldma_domain, irq);
+ switch (d->hwirq) {
+ case XILINX_PCIE_INTR_CORRECTABLE:
+ case XILINX_PCIE_INTR_NONFATAL:
+ case XILINX_PCIE_INTR_FATAL:
+ xilinx_pl_dma_pcie_clear_err_interrupts(port);
+ fallthrough;
+
+ default:
+ if (intr_cause[d->hwirq].str)
+ dev_warn(dev, "%s\n", intr_cause[d->hwirq].str);
+ else
+ dev_warn(dev, "Unknown IRQ %ld\n", d->hwirq);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static struct irq_chip xilinx_msi_irq_chip = {
+ .name = "pl_dma:PCIe MSI",
+ .irq_enable = pci_msi_unmask_irq,
+ .irq_disable = pci_msi_mask_irq,
+ .irq_mask = pci_msi_mask_irq,
+ .irq_unmask = pci_msi_unmask_irq,
+};
+
+static struct msi_domain_info xilinx_msi_domain_info = {
+ .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
+ MSI_FLAG_MULTI_PCI_MSI),
+ .chip = &xilinx_msi_irq_chip,
+};
+
+static void xilinx_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
+{
+ struct pl_dma_pcie *pcie = irq_data_get_irq_chip_data(data);
+ phys_addr_t msi_addr = pcie->phys_reg_base;
+
+ msg->address_lo = lower_32_bits(msi_addr);
+ msg->address_hi = upper_32_bits(msi_addr);
+ msg->data = data->hwirq;
+}
+
+static int xilinx_msi_set_affinity(struct irq_data *irq_data,
+ const struct cpumask *mask, bool force)
+{
+ return -EINVAL;
+}
+
+static struct irq_chip xilinx_irq_chip = {
+ .name = "pl_dma:MSI",
+ .irq_compose_msi_msg = xilinx_compose_msi_msg,
+ .irq_set_affinity = xilinx_msi_set_affinity,
+};
+
+static int xilinx_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs, void *args)
+{
+ struct pl_dma_pcie *pcie = domain->host_data;
+ struct xilinx_msi *msi = &pcie->msi;
+ int bit, i;
+
+ mutex_lock(&msi->lock);
+ bit = bitmap_find_free_region(msi->bitmap, XILINX_NUM_MSI_IRQS,
+ get_count_order(nr_irqs));
+ if (bit < 0) {
+ mutex_unlock(&msi->lock);
+ return -ENOSPC;
+ }
+
+ for (i = 0; i < nr_irqs; i++) {
+ irq_domain_set_info(domain, virq + i, bit + i, &xilinx_irq_chip,
+ domain->host_data, handle_simple_irq,
+ NULL, NULL);
+ }
+ mutex_unlock(&msi->lock);
+ return 0;
+}
+
+static void xilinx_irq_domain_free(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs)
+{
+ struct irq_data *data = irq_domain_get_irq_data(domain, virq);
+ struct pl_dma_pcie *pcie = irq_data_get_irq_chip_data(data);
+ struct xilinx_msi *msi = &pcie->msi;
+
+ mutex_lock(&msi->lock);
+ bitmap_release_region(msi->bitmap, data->hwirq,
+ get_count_order(nr_irqs));
+ mutex_unlock(&msi->lock);
+}
+
+static const struct irq_domain_ops dev_msi_domain_ops = {
+ .alloc = xilinx_irq_domain_alloc,
+ .free = xilinx_irq_domain_free,
+};
+
+static void xilinx_pl_dma_pcie_free_irq_domains(struct pl_dma_pcie *port)
+{
+ struct xilinx_msi *msi = &port->msi;
+
+ if (port->intx_domain) {
+ irq_domain_remove(port->intx_domain);
+ port->intx_domain = NULL;
+ }
+
+ if (msi->dev_domain) {
+ irq_domain_remove(msi->dev_domain);
+ msi->dev_domain = NULL;
+ }
+
+ if (msi->msi_domain) {
+ irq_domain_remove(msi->msi_domain);
+ msi->msi_domain = NULL;
+ }
+}
+
+static int xilinx_pl_dma_pcie_init_msi_irq_domain(struct pl_dma_pcie *port)
+{
+ struct device *dev = port->dev;
+ struct xilinx_msi *msi = &port->msi;
+ int size = BITS_TO_LONGS(XILINX_NUM_MSI_IRQS) * sizeof(long);
+ struct fwnode_handle *fwnode = of_node_to_fwnode(port->dev->of_node);
+
+ msi->dev_domain = irq_domain_add_linear(NULL, XILINX_NUM_MSI_IRQS,
+ &dev_msi_domain_ops, port);
+ if (!msi->dev_domain)
+ goto out;
+
+ msi->msi_domain = pci_msi_create_irq_domain(fwnode,
+ &xilinx_msi_domain_info,
+ msi->dev_domain);
+ if (!msi->msi_domain)
+ goto out;
+
+ mutex_init(&msi->lock);
+ msi->bitmap = kzalloc(size, GFP_KERNEL);
+ if (!msi->bitmap)
+ goto out;
+
+ raw_spin_lock_init(&port->lock);
+ xilinx_pl_dma_pcie_enable_msi(port);
+
+ return 0;
+
+out:
+ xilinx_pl_dma_pcie_free_irq_domains(port);
+ dev_err(dev, "Failed to allocate MSI IRQ domains\n");
+ return -ENOMEM;
+}
+
+/* INTx error interrupts are Xilinx controller specific interrupt, used to
+ * notify user about errors such as cfg timeout, slave unsupported requests,
+ * fatal and non fatal error etc.
+ */
+
+static irqreturn_t xilinx_pl_dma_pcie_intx_flow(int irq, void *args)
+{
+ unsigned long val;
+ int i;
+ struct pl_dma_pcie *port = args;
+
+ val = FIELD_GET(XILINX_PCIE_DMA_IDRN_MASK,
+ pcie_read(port, XILINX_PCIE_DMA_REG_IDRN));
+
+ for_each_set_bit(i, &val, PCI_NUM_INTX)
+ generic_handle_domain_irq(port->intx_domain, i);
+ return IRQ_HANDLED;
+}
+
+static void xilinx_pl_dma_pcie_mask_event_irq(struct irq_data *d)
+{
+ struct pl_dma_pcie *port = irq_data_get_irq_chip_data(d);
+ u32 val;
+
+ raw_spin_lock(&port->lock);
+ val = pcie_read(port, XILINX_PCIE_DMA_REG_IMR);
+ val &= ~BIT(d->hwirq);
+ pcie_write(port, val, XILINX_PCIE_DMA_REG_IMR);
+ raw_spin_unlock(&port->lock);
+}
+
+static void xilinx_pl_dma_pcie_unmask_event_irq(struct irq_data *d)
+{
+ struct pl_dma_pcie *port = irq_data_get_irq_chip_data(d);
+ u32 val;
+
+ raw_spin_lock(&port->lock);
+ val = pcie_read(port, XILINX_PCIE_DMA_REG_IMR);
+ val |= BIT(d->hwirq);
+ pcie_write(port, val, XILINX_PCIE_DMA_REG_IMR);
+ raw_spin_unlock(&port->lock);
+}
+
+static struct irq_chip xilinx_pl_dma_pcie_event_irq_chip = {
+ .name = "pl_dma:RC-Event",
+ .irq_mask = xilinx_pl_dma_pcie_mask_event_irq,
+ .irq_unmask = xilinx_pl_dma_pcie_unmask_event_irq,
+};
+
+static int xilinx_pl_dma_pcie_event_map(struct irq_domain *domain,
+ unsigned int irq, irq_hw_number_t hwirq)
+{
+ irq_set_chip_and_handler(irq, &xilinx_pl_dma_pcie_event_irq_chip,
+ handle_level_irq);
+ irq_set_chip_data(irq, domain->host_data);
+ irq_set_status_flags(irq, IRQ_LEVEL);
+
+ return 0;
+}
+
+static const struct irq_domain_ops event_domain_ops = {
+ .map = xilinx_pl_dma_pcie_event_map,
+};
+
+/**
+ * xilinx_pl_dma_pcie_init_irq_domain - Initialize IRQ domain
+ * @port: PCIe port information
+ *
+ * Return: '0' on success and error value on failure
+ */
+static int xilinx_pl_dma_pcie_init_irq_domain(struct pl_dma_pcie *port)
+{
+ struct device *dev = port->dev;
+ struct device_node *node = dev->of_node;
+ struct device_node *pcie_intc_node;
+ int ret;
+
+ /* Setup INTx */
+ pcie_intc_node = of_get_child_by_name(node, "interrupt-controller");
+ if (!pcie_intc_node) {
+ dev_err(dev, "No PCIe Intc node found\n");
+ return -EINVAL;
+ }
+
+ port->pldma_domain = irq_domain_add_linear(pcie_intc_node, 32,
+ &event_domain_ops, port);
+ if (!port->pldma_domain)
+ return -ENOMEM;
+
+ irq_domain_update_bus_token(port->pldma_domain, DOMAIN_BUS_NEXUS);
+
+ port->intx_domain = irq_domain_add_linear(pcie_intc_node, PCI_NUM_INTX,
+ &intx_domain_ops, port);
+ if (!port->intx_domain) {
+ dev_err(dev, "Failed to get a INTx IRQ domain\n");
+ return PTR_ERR(port->intx_domain);
+ }
+
+ irq_domain_update_bus_token(port->intx_domain, DOMAIN_BUS_WIRED);
+
+ ret = xilinx_pl_dma_pcie_init_msi_irq_domain(port);
+ if (ret != 0) {
+ irq_domain_remove(port->intx_domain);
+ return -ENOMEM;
+ }
+
+ of_node_put(pcie_intc_node);
+ raw_spin_lock_init(&port->lock);
+
+ return 0;
+}
+
+static int xilinx_pl_dma_pcie_setup_irq(struct pl_dma_pcie *port)
+{
+ struct device *dev = port->dev;
+ struct platform_device *pdev = to_platform_device(dev);
+ int i, irq, err;
+
+ port->irq = platform_get_irq(pdev, 0);
+ if (port->irq < 0)
+ return port->irq;
+
+ for (i = 0; i < ARRAY_SIZE(intr_cause); i++) {
+ int err;
+
+ if (!intr_cause[i].str)
+ continue;
+
+ irq = irq_create_mapping(port->pldma_domain, i);
+ if (!irq) {
+ dev_err(dev, "Failed to map interrupt\n");
+ return -ENXIO;
+ }
+
+ err = devm_request_irq(dev, irq,
+ xilinx_pl_dma_pcie_intr_handler,
+ IRQF_SHARED | IRQF_NO_THREAD,
+ intr_cause[i].sym, port);
+ if (err) {
+ dev_err(dev, "Failed to request IRQ %d\n", irq);
+ return err;
+ }
+ }
+
+ port->intx_irq = irq_create_mapping(port->pldma_domain,
+ XILINX_PCIE_INTR_INTX);
+ if (!port->intx_irq) {
+ dev_err(dev, "Failed to map INTx interrupt\n");
+ return -ENXIO;
+ }
+
+ err = devm_request_irq(dev, port->intx_irq, xilinx_pl_dma_pcie_intx_flow,
+ IRQF_SHARED | IRQF_NO_THREAD, NULL, port);
+ if (err) {
+ dev_err(dev, "Failed to request INTx IRQ %d\n", irq);
+ return err;
+ }
+ err = devm_request_irq(dev, port->irq, xilinx_pl_dma_pcie_event_flow,
+ IRQF_SHARED | IRQF_NO_THREAD, NULL, port);
+ if (err) {
+ dev_err(dev, "Failed to request event IRQ %d\n", irq);
+ return err;
+ }
+ return 0;
+}
+
+static void xilinx_pl_dma_pcie_init_port(struct pl_dma_pcie *port)
+{
+ if (xilinx_pl_dma_pcie_link_up(port))
+ dev_info(port->dev, "PCIe Link is UP\n");
+ else
+ dev_info(port->dev, "PCIe Link is DOWN\n");
+
+ /* Disable all interrupts */
+ pcie_write(port, ~XILINX_PCIE_DMA_IDR_ALL_MASK,
+ XILINX_PCIE_DMA_REG_IMR);
+
+ /* Clear pending interrupts */
+ pcie_write(port, pcie_read(port, XILINX_PCIE_DMA_REG_IDR) &
+ XILINX_PCIE_DMA_IMR_ALL_MASK,
+ XILINX_PCIE_DMA_REG_IDR);
+
+ /* Needed for MSI DECODE MODE */
+ pcie_write(port, XILINX_PCIE_DMA_IDR_ALL_MASK,
+ XILINX_PCIE_DMA_REG_MSI_LOW_MASK);
+ pcie_write(port, XILINX_PCIE_DMA_IDR_ALL_MASK,
+ XILINX_PCIE_DMA_REG_MSI_HI_MASK);
+
+ /* Set the Bridge enable bit */
+ pcie_write(port, pcie_read(port, XILINX_PCIE_DMA_REG_RPSC) |
+ XILINX_PCIE_DMA_REG_RPSC_BEN,
+ XILINX_PCIE_DMA_REG_RPSC);
+}
+
+static int xilinx_request_msi_irq(struct pl_dma_pcie *port)
+{
+ struct device *dev = port->dev;
+ struct platform_device *pdev = to_platform_device(dev);
+ int ret;
+
+ port->msi.irq_msi0 = platform_get_irq_byname(pdev, "msi0");
+ if (port->msi.irq_msi0 <= 0) {
+ dev_err(dev, "Unable to find msi0 IRQ line\n");
+ return port->msi.irq_msi0;
+ }
+ ret = devm_request_irq(dev, port->msi.irq_msi0, xilinx_pl_dma_pcie_msi_handler_low,
+ IRQF_SHARED | IRQF_NO_THREAD, "xlnx-pcie-dma-pl",
+ port);
+ if (ret) {
+ dev_err(dev, "Failed to register interrupt\n");
+ return ret;
+ }
+ port->msi.irq_msi1 = platform_get_irq_byname(pdev, "msi1");
+ if (port->msi.irq_msi1 <= 0) {
+ dev_err(dev, "Unable to find msi1 IRQ line\n");
+ return port->msi.irq_msi1;
+ }
+ ret = devm_request_irq(dev, port->msi.irq_msi1, xilinx_pl_dma_pcie_msi_handler_high,
+ IRQF_SHARED | IRQF_NO_THREAD, "xlnx-pcie-dma-pl",
+ port);
+ if (ret) {
+ dev_err(dev, "Failed to register interrupt\n");
+ return ret;
+ }
+ return 0;
+}
+
+static int xilinx_pl_dma_pcie_parse_dt(struct pl_dma_pcie *port,
+ struct resource *bus_range)
+{
+ struct device *dev = port->dev;
+ struct platform_device *pdev = to_platform_device(dev);
+ struct resource *res;
+ int err;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ dev_err(dev, "Missing \"reg\" property\n");
+ return -ENXIO;
+ }
+ port->phys_reg_base = res->start;
+
+ port->cfg = pci_ecam_create(dev, res, bus_range, &xilinx_pl_dma_pcie_ops);
+ if (IS_ERR(port->cfg))
+ return PTR_ERR(port->cfg);
+
+ port->reg_base = port->cfg->win;
+
+ err = xilinx_request_msi_irq(port);
+ if (err) {
+ pci_ecam_free(port->cfg);
+ return err;
+ }
+
+ return 0;
+}
+
+static int xilinx_pl_dma_pcie_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct pl_dma_pcie *port;
+ struct pci_host_bridge *bridge;
+ struct resource_entry *bus;
+ int err;
+
+ bridge = devm_pci_alloc_host_bridge(dev, sizeof(*port));
+ if (!bridge)
+ return -ENODEV;
+
+ port = pci_host_bridge_priv(bridge);
+
+ port->dev = dev;
+
+ bus = resource_list_first_type(&bridge->windows, IORESOURCE_BUS);
+ if (!bus)
+ return -ENODEV;
+
+ err = xilinx_pl_dma_pcie_parse_dt(port, bus->res);
+ if (err) {
+ dev_err(dev, "Parsing DT failed\n");
+ return err;
+ }
+
+ xilinx_pl_dma_pcie_init_port(port);
+
+ err = xilinx_pl_dma_pcie_init_irq_domain(port);
+ if (err)
+ goto err_irq_domain;
+
+ err = xilinx_pl_dma_pcie_setup_irq(port);
+
+ bridge->sysdata = port;
+ bridge->ops = &xilinx_pl_dma_pcie_ops.pci_ops;
+
+ err = pci_host_probe(bridge);
+ if (err < 0)
+ goto err_host_bridge;
+
+ return 0;
+
+err_host_bridge:
+ xilinx_pl_dma_pcie_free_irq_domains(port);
+
+err_irq_domain:
+ pci_ecam_free(port->cfg);
+ return err;
+}
+
+static const struct of_device_id xilinx_pl_dma_pcie_of_match[] = {
+ {
+ .compatible = "xlnx,xdma-host-3.00",
+ },
+ {}
+};
+
+static struct platform_driver xilinx_pl_dma_pcie_driver = {
+ .driver = {
+ .name = "xilinx-xdma-pcie",
+ .of_match_table = xilinx_pl_dma_pcie_of_match,
+ .suppress_bind_attrs = true,
+ },
+ .probe = xilinx_pl_dma_pcie_probe,
+};
+
+builtin_platform_driver(xilinx_pl_dma_pcie_driver);
--
1.8.3.1