Re: [PATCH v3 1/2] PCI: cadence: Refactor driver to use as a core library

From: Kishon Vijay Abraham I
Date: Thu Dec 05 2019 - 06:23:04 EST


Hi Tom,

On 29/10/19 5:15 pm, Tom Joseph wrote:
Cadence PCIe host and endpoint IP may be embedded into a variety of
SoCs/platforms. Let's extract the platform related APIs/Structures in the
current driver to a separate file (pcie-cadence-plat.c), such that the
common functionality can be used by future platforms.

Signed-off-by: Tom Joseph <tjoseph@xxxxxxxxxxx>
---
drivers/pci/controller/Kconfig | 31 +++--
drivers/pci/controller/Makefile | 1 +
drivers/pci/controller/pcie-cadence-ep.c | 96 +---------------
drivers/pci/controller/pcie-cadence-host.c | 95 ++--------------
drivers/pci/controller/pcie-cadence-plat.c | 174 +++++++++++++++++++++++++++++
drivers/pci/controller/pcie-cadence.h | 77 +++++++++++++
6 files changed, 287 insertions(+), 187 deletions(-)
create mode 100644 drivers/pci/controller/pcie-cadence-plat.c

.
.
<snip>
.
.> diff --git a/drivers/pci/controller/pcie-cadence-ep.c b/drivers/pci/controller/pcie-cadence-ep.c
index def7820..1c173da 100644
--- a/drivers/pci/controller/pcie-cadence-ep.c
+++ b/drivers/pci/controller/pcie-cadence-ep.c
@@ -17,35 +17,6 @@
#define CDNS_PCIE_EP_IRQ_PCI_ADDR_NONE 0x1
#define CDNS_PCIE_EP_IRQ_PCI_ADDR_LEGACY 0x3
-/**
- * struct cdns_pcie_ep - private data for this PCIe endpoint controller driver
- * @pcie: Cadence PCIe controller
- * @max_regions: maximum number of regions supported by hardware
- * @ob_region_map: bitmask of mapped outbound regions
- * @ob_addr: base addresses in the AXI bus where the outbound regions start
- * @irq_phys_addr: base address on the AXI bus where the MSI/legacy IRQ
- * dedicated outbound regions is mapped.
- * @irq_cpu_addr: base address in the CPU space where a write access triggers
- * the sending of a memory write (MSI) / normal message (legacy
- * IRQ) TLP through the PCIe bus.
- * @irq_pci_addr: used to save the current mapping of the MSI/legacy IRQ
- * dedicated outbound region.
- * @irq_pci_fn: the latest PCI function that has updated the mapping of
- * the MSI/legacy IRQ dedicated outbound region.
- * @irq_pending: bitmask of asserted legacy IRQs.
- */
-struct cdns_pcie_ep {
- struct cdns_pcie pcie;
- u32 max_regions;
- unsigned long ob_region_map;
- phys_addr_t *ob_addr;
- phys_addr_t irq_phys_addr;
- void __iomem *irq_cpu_addr;
- u64 irq_pci_addr;
- u8 irq_pci_fn;
- u8 irq_pending;
-};
-
static int cdns_pcie_ep_write_header(struct pci_epc *epc, u8 fn,
struct pci_epf_header *hdr)
{
@@ -424,28 +395,17 @@ static const struct pci_epc_ops cdns_pcie_epc_ops = {
.get_features = cdns_pcie_ep_get_features,
};
-static const struct of_device_id cdns_pcie_ep_of_match[] = {
- { .compatible = "cdns,cdns-pcie-ep" },
-
- { },
-};
-static int cdns_pcie_ep_probe(struct platform_device *pdev)
+int cdns_pcie_ep_setup(struct cdns_pcie_ep *ep)
{
- struct device *dev = &pdev->dev;
+ struct device *dev = ep->pcie.dev;
+ struct platform_device *pdev = to_platform_device(dev);
struct device_node *np = dev->of_node;
- struct cdns_pcie_ep *ep;
- struct cdns_pcie *pcie;
- struct pci_epc *epc;
+ struct cdns_pcie *pcie = &ep->pcie;
struct resource *res;
+ struct pci_epc *epc;
int ret;
- int phy_count;
-
- ep = devm_kzalloc(dev, sizeof(*ep), GFP_KERNEL);
- if (!ep)
- return -ENOMEM;
- pcie = &ep->pcie;
pcie->is_rc = false;
res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "reg");
@@ -474,19 +434,6 @@ static int cdns_pcie_ep_probe(struct platform_device *pdev)
if (!ep->ob_addr)
return -ENOMEM;
- ret = cdns_pcie_init_phy(dev, pcie);
- if (ret) {
- dev_err(dev, "failed to init phy\n");
- return ret;
- }
- platform_set_drvdata(pdev, pcie);
- pm_runtime_enable(dev);
- ret = pm_runtime_get_sync(dev);
- if (ret < 0) {
- dev_err(dev, "pm_runtime_get_sync() failed\n");
- goto err_get_sync;
- }
-
/* Disable all but function 0 (anyway BIT(0) is hardwired to 1). */
cdns_pcie_writel(pcie, CDNS_PCIE_LM_EP_FUNC_CFG, BIT(0));
@@ -528,38 +475,5 @@ static int cdns_pcie_ep_probe(struct platform_device *pdev)
err_init:
pm_runtime_put_sync(dev);

put_sync shouldn't be there. Please fix the error handling.
- err_get_sync:
- pm_runtime_disable(dev);
- cdns_pcie_disable_phy(pcie);
- phy_count = pcie->phy_count;
- while (phy_count--)
- device_link_del(pcie->link[phy_count]);
-
return ret;
}
-
-static void cdns_pcie_ep_shutdown(struct platform_device *pdev)
-{
- struct device *dev = &pdev->dev;
- struct cdns_pcie *pcie = dev_get_drvdata(dev);
- int ret;
-
- ret = pm_runtime_put_sync(dev);
- if (ret < 0)
- dev_dbg(dev, "pm_runtime_put_sync failed\n");
-
- pm_runtime_disable(dev);
-
- cdns_pcie_disable_phy(pcie);
-}
-
-static struct platform_driver cdns_pcie_ep_driver = {
- .driver = {
- .name = "cdns-pcie-ep",
- .of_match_table = cdns_pcie_ep_of_match,
- .pm = &cdns_pcie_pm_ops,
- },
- .probe = cdns_pcie_ep_probe,
- .shutdown = cdns_pcie_ep_shutdown,
-};
-builtin_platform_driver(cdns_pcie_ep_driver);
diff --git a/drivers/pci/controller/pcie-cadence-host.c b/drivers/pci/controller/pcie-cadence-host.c
index 97e2510..8a42afd 100644
--- a/drivers/pci/controller/pcie-cadence-host.c
+++ b/drivers/pci/controller/pcie-cadence-host.c
@@ -11,33 +11,6 @@
#include "pcie-cadence.h"
-/**
- * struct cdns_pcie_rc - private data for this PCIe Root Complex driver
- * @pcie: Cadence PCIe controller
- * @dev: pointer to PCIe device
- * @cfg_res: start/end offsets in the physical system memory to map PCI
- * configuration space accesses
- * @bus_range: first/last buses behind the PCIe host controller
- * @cfg_base: IO mapped window to access the PCI configuration space of a
- * single function at a time
- * @max_regions: maximum number of regions supported by the hardware
- * @no_bar_nbits: Number of bits to keep for inbound (PCIe -> CPU) address
- * translation (nbits sets into the "no BAR match" register)
- * @vendor_id: PCI vendor ID
- * @device_id: PCI device ID
- */
-struct cdns_pcie_rc {
- struct cdns_pcie pcie;
- struct device *dev;
- struct resource *cfg_res;
- struct resource *bus_range;
- void __iomem *cfg_base;
- u32 max_regions;
- u32 no_bar_nbits;
- u16 vendor_id;
- u16 device_id;
-};
-
static void __iomem *cdns_pci_map_bus(struct pci_bus *bus, unsigned int devfn,
int where)
{
@@ -92,11 +65,6 @@ static struct pci_ops cdns_pcie_host_ops = {
.write = pci_generic_config_write,
};
-static const struct of_device_id cdns_pcie_host_of_match[] = {
- { .compatible = "cdns,cdns-pcie-host" },
-
- { },
-};
static int cdns_pcie_host_init_root_port(struct cdns_pcie_rc *rc)
{
@@ -136,10 +104,10 @@ static int cdns_pcie_host_init_root_port(struct cdns_pcie_rc *rc)
static int cdns_pcie_host_init_address_translation(struct cdns_pcie_rc *rc)
{
struct cdns_pcie *pcie = &rc->pcie;
- struct resource *cfg_res = rc->cfg_res;
struct resource *mem_res = pcie->mem_res;
struct resource *bus_range = rc->bus_range;
- struct device *dev = rc->dev;
+ struct resource *cfg_res = rc->cfg_res;
+ struct device *dev = pcie->dev;
struct device_node *np = dev->of_node;
struct of_pci_range_parser parser;
struct of_pci_range range;
@@ -233,25 +201,21 @@ static int cdns_pcie_host_init(struct device *dev,
return err;
}
-static int cdns_pcie_host_probe(struct platform_device *pdev)
+int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
{
- struct device *dev = &pdev->dev;
+ struct device *dev = rc->pcie.dev;
+ struct platform_device *pdev = to_platform_device(dev);
struct device_node *np = dev->of_node;
struct pci_host_bridge *bridge;
struct list_head resources;
- struct cdns_pcie_rc *rc;
struct cdns_pcie *pcie;
struct resource *res;
int ret;
- int phy_count;
- bridge = devm_pci_alloc_host_bridge(dev, sizeof(*rc));
+ bridge = pci_host_bridge_from_priv(rc);
if (!bridge)
return -ENOMEM;
- rc = pci_host_bridge_priv(bridge);
- rc->dev = dev;
-
pcie = &rc->pcie;
pcie->is_rc = true;
@@ -287,21 +251,8 @@ static int cdns_pcie_host_probe(struct platform_device *pdev)
dev_err(dev, "missing \"mem\"\n");
return -EINVAL;
}
- pcie->mem_res = res;
- ret = cdns_pcie_init_phy(dev, pcie);
- if (ret) {
- dev_err(dev, "failed to init phy\n");
- return ret;
- }
- platform_set_drvdata(pdev, pcie);
-
- pm_runtime_enable(dev);
- ret = pm_runtime_get_sync(dev);
- if (ret < 0) {
- dev_err(dev, "pm_runtime_get_sync() failed\n");
- goto err_get_sync;
- }
+ pcie->mem_res = res;
ret = cdns_pcie_host_init(dev, &resources, rc);
if (ret)
@@ -326,37 +277,5 @@ static int cdns_pcie_host_probe(struct platform_device *pdev)
err_init:
pm_runtime_put_sync(dev);
- err_get_sync:
- pm_runtime_disable(dev);
- cdns_pcie_disable_phy(pcie);
- phy_count = pcie->phy_count;
- while (phy_count--)
- device_link_del(pcie->link[phy_count]);
-
return ret;
}
-
-static void cdns_pcie_shutdown(struct platform_device *pdev)
-{
- struct device *dev = &pdev->dev;
- struct cdns_pcie *pcie = dev_get_drvdata(dev);
- int ret;
-
- ret = pm_runtime_put_sync(dev);
- if (ret < 0)
- dev_dbg(dev, "pm_runtime_put_sync failed\n");
-
- pm_runtime_disable(dev);
- cdns_pcie_disable_phy(pcie);
-}
-
-static struct platform_driver cdns_pcie_host_driver = {
- .driver = {
- .name = "cdns-pcie-host",
- .of_match_table = cdns_pcie_host_of_match,
- .pm = &cdns_pcie_pm_ops,
- },
- .probe = cdns_pcie_host_probe,
- .shutdown = cdns_pcie_shutdown,
-};
-builtin_platform_driver(cdns_pcie_host_driver);
diff --git a/drivers/pci/controller/pcie-cadence-plat.c b/drivers/pci/controller/pcie-cadence-plat.c
new file mode 100644
index 0000000..f5c6bf6
--- /dev/null
+++ b/drivers/pci/controller/pcie-cadence-plat.c
@@ -0,0 +1,174 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Cadence PCIe platform driver.
+ *
+ * Copyright (c) 2019, Cadence Design Systems
+ * Author: Tom Joseph <tjoseph@xxxxxxxxxxx>
+ */
+#include <linux/kernel.h>
+#include <linux/of_address.h>
+#include <linux/of_pci.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/of_device.h>
+#include "pcie-cadence.h"
+
+/**
+ * struct cdns_plat_pcie - private data for this PCIe platform driver
+ * @pcie: Cadence PCIe controller
+ * @is_rc: Set to 1 indicates the PCIe controller mode is Root Complex,
+ * if 0 it is in Endpoint mode.
+ */
+struct cdns_plat_pcie {
+ struct cdns_pcie *pcie;
+ bool is_rc;
+};
+
+struct cdns_plat_pcie_of_data {
+ bool is_rc;
+};
+
+static const struct of_device_id cdns_plat_pcie_of_match[];
+
+static int cdns_plat_pcie_probe(struct platform_device *pdev)
+{
+ const struct cdns_plat_pcie_of_data *data;
+ struct cdns_plat_pcie *cdns_plat_pcie;
+ const struct of_device_id *match;
+ struct device *dev = &pdev->dev;
+ struct pci_host_bridge *bridge;
+ struct cdns_pcie_ep *ep;
+ struct cdns_pcie_rc *rc;
+ int phy_count;
+ bool is_rc;
+ int ret;
+
+ match = of_match_device(cdns_plat_pcie_of_match, dev);
+ if (!match)
+ return -EINVAL;
+
+ data = (struct cdns_plat_pcie_of_data *)match->data;
+ is_rc = data->is_rc;
+
+ pr_debug(" Started %s with is_rc: %d\n", __func__, is_rc);
+ cdns_plat_pcie = devm_kzalloc(dev, sizeof(*cdns_plat_pcie), GFP_KERNEL);
+ if (!cdns_plat_pcie)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, cdns_plat_pcie);
+ if (is_rc) {
+ if (!IS_ENABLED(CONFIG_PCIE_CADENCE_PLAT_HOST))
+ return -ENODEV;
+
+ bridge = devm_pci_alloc_host_bridge(dev, sizeof(*rc));
+ if (!bridge)
+ return -ENOMEM;
+
+ rc = pci_host_bridge_priv(bridge);
+ rc->pcie.dev = dev;
+ cdns_plat_pcie->pcie = &rc->pcie;
+ cdns_plat_pcie->is_rc = is_rc;
+
+ ret = cdns_pcie_init_phy(dev, cdns_plat_pcie->pcie);
+ if (ret) {
+ dev_err(dev, "failed to init phy\n");
+ return ret;
+ }
+ pm_runtime_enable(dev);
+ ret = pm_runtime_get_sync(dev);
+ if (ret < 0) {
+ dev_err(dev, "pm_runtime_get_sync() failed\n");
+ goto err_get_sync;
+ }
+
+ ret = cdns_pcie_host_setup(rc);
+ if (ret)
+ goto err_init;
+ } else {
+ if (!IS_ENABLED(CONFIG_PCIE_CADENCE_PLAT_EP))
+ return -ENODEV;
+
+ ep = devm_kzalloc(dev, sizeof(*ep), GFP_KERNEL);
+ if (!ep)
+ return -ENOMEM;
+
+ ep->pcie.dev = dev;
+ cdns_plat_pcie->pcie = &ep->pcie;
+ cdns_plat_pcie->is_rc = is_rc;
+
+ ret = cdns_pcie_init_phy(dev, cdns_plat_pcie->pcie);
+ if (ret) {
+ dev_err(dev, "failed to init phy\n");
+ return ret;
+ }
+
+ pm_runtime_enable(dev);
+ ret = pm_runtime_get_sync(dev);
+ if (ret < 0) {
+ dev_err(dev, "pm_runtime_get_sync() failed\n");
+ goto err_get_sync;
+ }
+
+ ret = cdns_pcie_ep_setup(ep);
+ if (ret)
+ goto err_init;
+ }
+
+ err_init:
+ pm_runtime_put_sync(dev);
+
+ err_get_sync:
+ pm_runtime_disable(dev);
+ cdns_pcie_disable_phy(cdns_plat_pcie->pcie);
+ phy_count = cdns_plat_pcie->pcie->phy_count;
+ while (phy_count--)
+ device_link_del(cdns_plat_pcie->pcie->link[phy_count]);
+
+ return 0;
+}
+
+static void cdns_plat_pcie_shutdown(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct cdns_pcie *pcie = dev_get_drvdata(dev);
+ int ret;
+
+ ret = pm_runtime_put_sync(dev);
+ if (ret < 0)
+ dev_dbg(dev, "pm_runtime_put_sync failed\n");
+
+ pm_runtime_disable(dev);
+
+ cdns_pcie_disable_phy(pcie);
+}
+
+static const struct cdns_plat_pcie_of_data cdns_plat_pcie_host_of_data = {
+ .is_rc = true,
+};
+
+static const struct cdns_plat_pcie_of_data cdns_plat_pcie_ep_of_data = {
+ .is_rc = false,
+};
+
+static const struct of_device_id cdns_plat_pcie_of_match[] = {
+ {
+ .compatible = "cdns,cdns-pcie-host",
+ .data = &cdns_plat_pcie_host_of_data,
+ },
+ {
+ .compatible = "cdns,cdns-pcie-ep",
+ .data = &cdns_plat_pcie_ep_of_data,
+ },
+ {},
+};
+
+static struct platform_driver cdns_plat_pcie_driver = {
+ .driver = {
+ .name = "cdns-pcie",
+ .of_match_table = cdns_plat_pcie_of_match,
+ .pm = &cdns_pcie_pm_ops,
+ },
+ .probe = cdns_plat_pcie_probe,
+ .shutdown = cdns_plat_pcie_shutdown,
+};
+builtin_platform_driver(cdns_plat_pcie_driver);
diff --git a/drivers/pci/controller/pcie-cadence.h b/drivers/pci/controller/pcie-cadence.h
index ae6bf2a..c98e858 100644
--- a/drivers/pci/controller/pcie-cadence.h
+++ b/drivers/pci/controller/pcie-cadence.h
@@ -190,6 +190,8 @@ enum cdns_pcie_rp_bar {
(((code) << 8) & CDNS_PCIE_NORMAL_MSG_CODE_MASK)
#define CDNS_PCIE_MSG_NO_DATA BIT(16)
+struct cdns_pcie;
+
enum cdns_pcie_msg_code {
MSG_CODE_ASSERT_INTA = 0x20,
MSG_CODE_ASSERT_INTB = 0x21,
@@ -231,13 +233,71 @@ enum cdns_pcie_msg_routing {
struct cdns_pcie {
void __iomem *reg_base;
struct resource *mem_res;
+ struct device *dev;
bool is_rc;
u8 bus;
int phy_count;
struct phy **phy;
struct device_link **link;
+ const struct cdns_pcie_common_ops *ops;

Where is cdns_pcie_common_ops defined?

+};
+
+/**
+ * struct cdns_pcie_rc - private data for this PCIe Root Complex driver
+ * @pcie: Cadence PCIe controller
+ * @dev: pointer to PCIe device
+ * @cfg_res: start/end offsets in the physical system memory to map PCI
+ * configuration space accesses
+ * @bus_range: first/last buses behind the PCIe host controller
+ * @cfg_base: IO mapped window to access the PCI configuration space of a
+ * single function at a time
+ * @max_regions: maximum number of regions supported by the hardware
+ * @no_bar_nbits: Number of bits to keep for inbound (PCIe -> CPU) address
+ * translation (nbits sets into the "no BAR match" register)
+ * @vendor_id: PCI vendor ID
+ * @device_id: PCI device ID
+ */
+struct cdns_pcie_rc {
+ struct cdns_pcie pcie;
+ struct resource *cfg_res;
+ struct resource *bus_range;
+ void __iomem *cfg_base;
+ u32 max_regions;
+ u32 no_bar_nbits;
+ u16 vendor_id;
+ u16 device_id;
};
+/**
+ * struct cdns_pcie_ep - private data for this PCIe endpoint controller driver
+ * @pcie: Cadence PCIe controller
+ * @max_regions: maximum number of regions supported by hardware
+ * @ob_region_map: bitmask of mapped outbound regions
+ * @ob_addr: base addresses in the AXI bus where the outbound regions start
+ * @irq_phys_addr: base address on the AXI bus where the MSI/legacy IRQ
+ * dedicated outbound regions is mapped.
+ * @irq_cpu_addr: base address in the CPU space where a write access triggers
+ * the sending of a memory write (MSI) / normal message (legacy
+ * IRQ) TLP through the PCIe bus.
+ * @irq_pci_addr: used to save the current mapping of the MSI/legacy IRQ
+ * dedicated outbound region.
+ * @irq_pci_fn: the latest PCI function that has updated the mapping of
+ * the MSI/legacy IRQ dedicated outbound region.
+ * @irq_pending: bitmask of asserted legacy IRQs.
+ */
+struct cdns_pcie_ep {
+ struct cdns_pcie pcie;
+ u32 max_regions;
+ unsigned long ob_region_map;
+ phys_addr_t *ob_addr;
+ phys_addr_t irq_phys_addr;
+ void __iomem *irq_cpu_addr;
+ u64 irq_pci_addr;
+ u8 irq_pci_fn;
+ u8 irq_pending;
+};
+
+
/* Register access */
static inline void cdns_pcie_writeb(struct cdns_pcie *pcie, u32 reg, u8 value)
{
@@ -306,6 +366,23 @@ static inline u32 cdns_pcie_ep_fn_readl(struct cdns_pcie *pcie, u8 fn, u32 reg)
return readl(pcie->reg_base + CDNS_PCIE_EP_FUNC_BASE(fn) + reg);
}
+#ifdef CONFIG_PCIE_CADENCE_HOST
+int cdns_pcie_host_setup(struct cdns_pcie_rc *rc);
+#else
+static inline int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
+{
+ return 0;
+}
+#endif
+
+#ifdef CONFIG_PCIE_CADENCE_EP
+int cdns_pcie_ep_setup(struct cdns_pcie_ep *ep);
+#else
+static inline int cdns_pcie_ep_setup(struct cdns_pcie_ep *ep)
+{
+ return 0;
+}
+#endif
void cdns_pcie_set_outbound_region(struct cdns_pcie *pcie, u8 fn,
u32 r, bool is_io,
u64 cpu_addr, u64 pci_addr, size_t size);