[RFC PATCH v2 1/1] PCI/ACPI: xgene: Add ECAM quirk for X-Gene PCIe controller

From: Duc Dang
Date: Tue Oct 25 2016 - 21:31:25 EST


PCIe controllers in X-Gene SoCs is not ECAM compliant: software
needs to configure additional controller's register to address
device at bus:dev:function.

This patch depends on "ECAM quirks handling for ARM64 platforms"
series (http://www.spinics.net/lists/arm-kernel/msg530692.html,
the series was also modified by Bjorn) to address the limitation
above for X-Gene PCIe controller.

The quirk will only be applied for X-Gene PCIe MCFG table with
OEM revison 1, 2, 3 or 4 (PCIe controller v1 and v2 on X-Gene SoCs).

Signed-off-by: Duc Dang <dhdang@xxxxxxx>
---
v2 changes:
1. Get rid of pci-xgene-ecam.c file and fold quirk code into pci-xgene.c
2. Redefine fixup array for X-Gene
3. Use devm_ioremap_resource to map csr_base

drivers/acpi/pci_mcfg.c | 30 ++++++++
drivers/pci/host/pci-xgene.c | 165 ++++++++++++++++++++++++++++++++++++++++++-
include/linux/pci-ecam.h | 5 ++
3 files changed, 197 insertions(+), 3 deletions(-)

diff --git a/drivers/acpi/pci_mcfg.c b/drivers/acpi/pci_mcfg.c
index bb2c508..9dfc937 100644
--- a/drivers/acpi/pci_mcfg.c
+++ b/drivers/acpi/pci_mcfg.c
@@ -96,6 +96,36 @@ struct mcfg_fixup {
THUNDER_ECAM_MCFG(2, 12),
THUNDER_ECAM_MCFG(2, 13),
#endif
+#ifdef CONFIG_PCI_XGENE
+#define XGENE_V1_ECAM_MCFG(rev, seg) \
+ {"APM ", "XGENE ", rev, seg, MCFG_BUS_ANY, \
+ &xgene_v1_pcie_ecam_ops }
+#define XGENE_V2_1_ECAM_MCFG(rev, seg) \
+ {"APM ", "XGENE ", rev, seg, MCFG_BUS_ANY, \
+ &xgene_v2_1_pcie_ecam_ops }
+#define XGENE_V2_2_ECAM_MCFG(rev, seg) \
+ {"APM ", "XGENE ", rev, seg, MCFG_BUS_ANY, \
+ &xgene_v2_2_pcie_ecam_ops }
+
+ /* X-Gene SoC with v1 PCIe controller */
+ XGENE_V1_ECAM_MCFG(1, 0),
+ XGENE_V1_ECAM_MCFG(1, 1),
+ XGENE_V1_ECAM_MCFG(1, 2),
+ XGENE_V1_ECAM_MCFG(1, 3),
+ XGENE_V1_ECAM_MCFG(1, 4),
+ XGENE_V1_ECAM_MCFG(2, 0),
+ XGENE_V1_ECAM_MCFG(2, 1),
+ XGENE_V1_ECAM_MCFG(2, 2),
+ XGENE_V1_ECAM_MCFG(2, 3),
+ XGENE_V1_ECAM_MCFG(2, 4),
+ /* X-Gene SoC with v2.1 PCIe controller */
+ XGENE_V2_1_ECAM_MCFG(3, 0),
+ XGENE_V2_1_ECAM_MCFG(3, 1),
+ /* X-Gene SoC with v2.2 PCIe controller */
+ XGENE_V2_2_ECAM_MCFG(4, 0),
+ XGENE_V2_2_ECAM_MCFG(4, 1),
+ XGENE_V2_2_ECAM_MCFG(4, 2),
+#endif
};

static char mcfg_oem_id[ACPI_OEM_ID_SIZE];
diff --git a/drivers/pci/host/pci-xgene.c b/drivers/pci/host/pci-xgene.c
index 1de23d7..d6aa642 100644
--- a/drivers/pci/host/pci-xgene.c
+++ b/drivers/pci/host/pci-xgene.c
@@ -27,6 +27,8 @@
#include <linux/of_irq.h>
#include <linux/of_pci.h>
#include <linux/pci.h>
+#include <linux/pci-acpi.h>
+#include <linux/pci-ecam.h>
#include <linux/platform_device.h>
#include <linux/slab.h>

@@ -64,6 +66,7 @@
/* PCIe IP version */
#define XGENE_PCIE_IP_VER_UNKN 0
#define XGENE_PCIE_IP_VER_1 1
+#define XGENE_PCIE_IP_VER_2 2

struct xgene_pcie_port {
struct device_node *node;
@@ -97,7 +100,15 @@ static inline u32 pcie_bar_low_val(u32 addr, u32 flags)
*/
static void __iomem *xgene_pcie_get_cfg_base(struct pci_bus *bus)
{
- struct xgene_pcie_port *port = bus->sysdata;
+ struct pci_config_window *cfg;
+ struct xgene_pcie_port *port;
+
+ if (acpi_disabled)
+ port = bus->sysdata;
+ else {
+ cfg = bus->sysdata;
+ port = cfg->priv;
+ }

if (bus->number >= (bus->primary + 1))
return port->cfg_base + AXI_EP_CFG_ACCESS;
@@ -111,10 +122,18 @@ static void __iomem *xgene_pcie_get_cfg_base(struct pci_bus *bus)
*/
static void xgene_pcie_set_rtdid_reg(struct pci_bus *bus, uint devfn)
{
- struct xgene_pcie_port *port = bus->sysdata;
+ struct pci_config_window *cfg;
+ struct xgene_pcie_port *port;
unsigned int b, d, f;
u32 rtdid_val = 0;

+ if (acpi_disabled)
+ port = bus->sysdata;
+ else {
+ cfg = bus->sysdata;
+ port = cfg->priv;
+ }
+
b = bus->number;
d = PCI_SLOT(devfn);
f = PCI_FUNC(devfn);
@@ -158,7 +177,15 @@ static void __iomem *xgene_pcie_map_bus(struct pci_bus *bus, unsigned int devfn,
static int xgene_pcie_config_read32(struct pci_bus *bus, unsigned int devfn,
int where, int size, u32 *val)
{
- struct xgene_pcie_port *port = bus->sysdata;
+ struct pci_config_window *cfg;
+ struct xgene_pcie_port *port;
+
+ if (acpi_disabled)
+ port = bus->sysdata;
+ else {
+ cfg = bus->sysdata;
+ port = cfg->priv;
+ }

if (pci_generic_config_read32(bus, devfn, where & ~0x3, 4, val) !=
PCIBIOS_SUCCESSFUL)
@@ -189,6 +216,138 @@ static int xgene_pcie_config_read32(struct pci_bus *bus, unsigned int devfn,
.write = pci_generic_config_write32,
};

+#ifdef CONFIG_ACPI
+static struct resource xgene_v1_csr_res[] = {
+ [0] = DEFINE_RES_MEM(0x1f2b0000UL, SZ_64K),
+ [1] = DEFINE_RES_MEM(0x1f2c0000UL, SZ_64K),
+ [2] = DEFINE_RES_MEM(0x1f2d0000UL, SZ_64K),
+ [3] = DEFINE_RES_MEM(0x1f500000UL, SZ_64K),
+ [4] = DEFINE_RES_MEM(0x1f510000UL, SZ_64K),
+};
+
+static int xgene_v1_pcie_ecam_init(struct pci_config_window *cfg)
+{
+ struct acpi_device *adev = to_acpi_device(cfg->parent);
+ struct acpi_pci_root *root = acpi_driver_data(adev);
+ struct device *dev = cfg->parent;
+ struct xgene_pcie_port *port;
+ struct resource *csr;
+
+ port = devm_kzalloc(dev, sizeof(*port), GFP_KERNEL);
+ if (!port)
+ return -ENOMEM;
+
+ csr = &xgene_v1_csr_res[root->segment];
+ port->csr_base = devm_ioremap_resource(dev, csr);
+ if (IS_ERR(port->csr_base)) {
+ kfree(port);
+ return -ENOMEM;
+ }
+
+ port->cfg_base = cfg->win;
+ port->version = XGENE_PCIE_IP_VER_1;
+
+ cfg->priv = port;
+
+ return 0;
+}
+
+struct pci_ecam_ops xgene_v1_pcie_ecam_ops = {
+ .bus_shift = 16,
+ .init = xgene_v1_pcie_ecam_init,
+ .pci_ops = {
+ .map_bus = xgene_pcie_map_bus,
+ .read = xgene_pcie_config_read32,
+ .write = pci_generic_config_write,
+ }
+};
+
+static struct resource xgene_v2_1_csr_res[] = {
+ [0] = DEFINE_RES_MEM(0x1f2b0000UL, SZ_64K),
+ [1] = DEFINE_RES_MEM(0x1f2c0000UL, SZ_64K),
+};
+
+static int xgene_v2_1_pcie_ecam_init(struct pci_config_window *cfg)
+{
+ struct acpi_device *adev = to_acpi_device(cfg->parent);
+ struct acpi_pci_root *root = acpi_driver_data(adev);
+ struct device *dev = cfg->parent;
+ struct xgene_pcie_port *port;
+ struct resource *csr;
+
+ port = devm_kzalloc(dev, sizeof(*port), GFP_KERNEL);
+ if (!port)
+ return -ENOMEM;
+
+ csr = &xgene_v2_1_csr_res[root->segment];
+ port->csr_base = devm_ioremap_resource(dev, csr);
+ if (IS_ERR(port->csr_base)) {
+ kfree(port);
+ return -ENOMEM;
+ }
+
+ port->cfg_base = cfg->win;
+ port->version = XGENE_PCIE_IP_VER_2;
+
+ cfg->priv = port;
+
+ return 0;
+}
+
+struct pci_ecam_ops xgene_v2_1_pcie_ecam_ops = {
+ .bus_shift = 16,
+ .init = xgene_v2_1_pcie_ecam_init,
+ .pci_ops = {
+ .map_bus = xgene_pcie_map_bus,
+ .read = xgene_pcie_config_read32,
+ .write = pci_generic_config_write,
+ }
+};
+
+static struct resource xgene_v2_2_csr_res[] = {
+ [0] = DEFINE_RES_MEM(0x1f2b0000UL, SZ_64K),
+ [1] = DEFINE_RES_MEM(0x1f500000UL, SZ_64K),
+ [2] = DEFINE_RES_MEM(0x1f2d0000UL, SZ_64K),
+};
+
+static int xgene_v2_2_pcie_ecam_init(struct pci_config_window *cfg)
+{
+ struct acpi_device *adev = to_acpi_device(cfg->parent);
+ struct acpi_pci_root *root = acpi_driver_data(adev);
+ struct device *dev = cfg->parent;
+ struct xgene_pcie_port *port;
+ struct resource *csr;
+
+ port = devm_kzalloc(dev, sizeof(*port), GFP_KERNEL);
+ if (!port)
+ return -ENOMEM;
+
+ csr = &xgene_v2_2_csr_res[root->segment];
+ port->csr_base = devm_ioremap_resource(dev, csr);
+ if (IS_ERR(port->csr_base)) {
+ kfree(port);
+ return -ENOMEM;
+ }
+
+ port->cfg_base = cfg->win;
+ port->version = XGENE_PCIE_IP_VER_2;
+
+ cfg->priv = port;
+
+ return 0;
+}
+
+struct pci_ecam_ops xgene_v2_2_pcie_ecam_ops = {
+ .bus_shift = 16,
+ .init = xgene_v2_2_pcie_ecam_init,
+ .pci_ops = {
+ .map_bus = xgene_pcie_map_bus,
+ .read = xgene_pcie_config_read32,
+ .write = pci_generic_config_write,
+ }
+};
+#endif
+
static u64 xgene_pcie_set_ib_mask(struct xgene_pcie_port *port, u32 addr,
u32 flags, u64 size)
{
diff --git a/include/linux/pci-ecam.h b/include/linux/pci-ecam.h
index 35f0e81..40da3e7 100644
--- a/include/linux/pci-ecam.h
+++ b/include/linux/pci-ecam.h
@@ -65,6 +65,11 @@ void __iomem *pci_ecam_map_bus(struct pci_bus *bus, unsigned int devfn,
#ifdef CONFIG_PCI_HOST_THUNDER_ECAM
extern struct pci_ecam_ops pci_thunder_ecam_ops;
#endif
+#ifdef CONFIG_PCI_XGENE
+extern struct pci_ecam_ops xgene_v1_pcie_ecam_ops;
+extern struct pci_ecam_ops xgene_v2_1_pcie_ecam_ops;
+extern struct pci_ecam_ops xgene_v2_2_pcie_ecam_ops;
+#endif

#ifdef CONFIG_PCI_HOST_GENERIC
/* for DT-based PCI controllers that support ECAM */
--
1.9.1