[RFC 2/4] PCI: generic: Add support for ARM64 and MSI(x)

suravee.suthikulpanit
2014-09-28T20:54:43Z

From: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>

This patch adds ARM64 support to the generic PCI host driver.

For MSI support, it adds new device tree binding "msi-parent",
which should point to corresponded msi-controller.

Cc: Will Deacon <will.deacon@arm.com>
Cc: Liviu Dudau <Liviu.Dudau@arm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
---
.../devicetree/bindings/pci/host-generic-pci.txt | 3 +
drivers/pci/host/Kconfig | 2 +-
drivers/pci/host/pci-host-generic.c | 95 ++++++++++++++++++++--
3 files changed, 90 insertions(+), 10 deletions(-)

diff --git a/Documentation/devicetree/bindings/pci/host-generic-pci.txt b/Documentation/devicetree/bindings/pci/host-generic-pci.txt
index f0b0436..327e5b1 100644
--- a/Documentation/devicetree/bindings/pci/host-generic-pci.txt
+++ b/Documentation/devicetree/bindings/pci/host-generic-pci.txt
@@ -69,6 +69,9 @@ Practice: Interrupt Mapping' and requires the following properties:

- interrupt-map-mask : <see aforementioned specification>

+Optinal Properties:
+
+- msi-parent : Specify the msi-controller phandle.

Example:

diff --git a/drivers/pci/host/Kconfig b/drivers/pci/host/Kconfig
index 90f5cca..44bf523 100644
--- a/drivers/pci/host/Kconfig
+++ b/drivers/pci/host/Kconfig
@@ -50,7 +50,7 @@ config PCI_RCAR_GEN2_PCIE

config PCI_HOST_GENERIC
bool "Generic PCI host controller"
- depends on ARM && OF
+ depends on (ARM || ARM64) && OF
help
Say Y here if you want to support a simple generic PCI host
controller, such as the one emulated by kvmtool.
diff --git a/drivers/pci/host/pci-host-generic.c b/drivers/pci/host/pci-host-generic.c
index 3d2076f..f33c547 100644
--- a/drivers/pci/host/pci-host-generic.c
+++ b/drivers/pci/host/pci-host-generic.c
@@ -42,14 +42,24 @@ struct gen_pci {
struct pci_host_bridge host;
struct gen_pci_cfg_windows cfg;
struct list_head resources;
+ struct device_node *msi_parent;
};

+#ifdef CONFIG_ARM64
+#define bus_to_gen_pci(b) \
+ ((struct gen_pci *)b->sysdata)
+#else
+#define bus_to_gen_pci(b) \
+ ((struct gen_pci *) \
+ (((struct pci_sys_data *) \
+ (bus->sysdata))->private_data))
+#endif
+
static void __iomem *gen_pci_map_cfg_bus_cam(struct pci_bus *bus,
unsigned int devfn,
int where)
{
- struct pci_sys_data *sys = bus->sysdata;
- struct gen_pci *pci = sys->private_data;
+ struct gen_pci *pci = bus_to_gen_pci(bus);
resource_size_t idx = bus->number - pci->cfg.bus_range.start;

return pci->cfg.win[idx] + ((devfn << 8) | where);
@@ -64,8 +74,7 @@ static void __iomem *gen_pci_map_cfg_bus_ecam(struct pci_bus *bus,
unsigned int devfn,
int where)
{
- struct pci_sys_data *sys = bus->sysdata;
- struct gen_pci *pci = sys->private_data;
+ struct gen_pci *pci = bus_to_gen_pci(bus);
resource_size_t idx = bus->number - pci->cfg.bus_range.start;

return pci->cfg.win[idx] + ((devfn << 12) | where);
@@ -80,8 +89,7 @@ static int gen_pci_config_read(struct pci_bus *bus, unsigned int devfn,
int where, int size, u32 *val)
{
void __iomem *addr;
- struct pci_sys_data *sys = bus->sysdata;
- struct gen_pci *pci = sys->private_data;
+ struct gen_pci *pci = bus_to_gen_pci(bus);

addr = pci->cfg.ops->map_bus(bus, devfn, where);

@@ -103,8 +111,7 @@ static int gen_pci_config_write(struct pci_bus *bus, unsigned int devfn,
int where, int size, u32 val)
{
void __iomem *addr;
- struct pci_sys_data *sys = bus->sysdata;
- struct gen_pci *pci = sys->private_data;
+ struct gen_pci *pci = bus_to_gen_pci(bus);

addr = pci->cfg.ops->map_bus(bus, devfn, where);

@@ -144,8 +151,11 @@ static int gen_pci_calc_io_offset(struct device *dev,
resource_size_t *offset)
{
static atomic_t wins = ATOMIC_INIT(0);
- int err, idx, max_win;
+ int idx, max_win;
unsigned int window;
+#ifndef CONFIG_ARM64
+ int err;
+#endif

if (!PAGE_ALIGNED(range->cpu_addr))
return -EINVAL;
@@ -156,9 +166,12 @@ static int gen_pci_calc_io_offset(struct device *dev,
return -ENOSPC;

window = (idx - 1) * SZ_64K;
+
+#ifndef CONFIG_ARM64
err = pci_ioremap_io(window, range->cpu_addr);
if (err)
return err;
+#endif

of_pci_range_to_resource(range, dev->of_node, res);
res->start = window;
@@ -310,12 +323,58 @@ static int gen_pci_parse_map_cfg_windows(struct gen_pci *pci)
return 0;
}

+#ifndef CONFIG_ARM64
static int gen_pci_setup(int nr, struct pci_sys_data *sys)
{
struct gen_pci *pci = sys->private_data;
list_splice_init(&pci->resources, &sys->resources);
return 1;
}
+#endif
+
+#ifdef CONFIG_ARM64
+struct pci_bus *gen_scan_root_bus(struct device *parent, int bus,
+ struct pci_ops *ops, void *sysdata,
+ struct list_head *resources)
+{
+ struct pci_host_bridge_window *window;
+ bool found = false;
+ struct pci_bus *b;
+ int max;
+ struct gen_pci *pci = sysdata;
+
+ list_for_each_entry(window, resources, list)
+ if (window->res->flags & IORESOURCE_BUS) {
+ found = true;
+ break;
+ }
+
+ b = pci_create_root_bus(parent, bus, ops, sysdata, resources);
+ if (!b)
+ return NULL;
+
+ /* TODO:
+ * This is probably should be done in the core pci driver somewhere
+ */
+ if (pci->msi_parent)
+ b->msi = of_pci_find_msi_chip_by_node(pci->msi_parent);
+
+ if (!found) {
+ dev_info(&b->dev,
+ "No busn resource found for root bus, will use [bus %02x-ff]\n",
+ bus);
+ pci_bus_insert_busn_res(b, bus, 255);
+ }
+
+ max = pci_scan_child_bus(b);
+
+ if (!found)
+ pci_bus_update_busn_res_end(b, max);
+
+ pci_bus_add_devices(b);
+ return b;
+}
+#endif

static int gen_pci_probe(struct platform_device *pdev)
{
@@ -326,6 +385,7 @@ static int gen_pci_probe(struct platform_device *pdev)
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
struct gen_pci *pci = devm_kzalloc(dev, sizeof(*pci), GFP_KERNEL);
+#ifndef CONFIG_ARM64
struct hw_pci hw = {
.nr_controllers = 1,
.private_data = (void **)&pci,
@@ -333,6 +393,7 @@ static int gen_pci_probe(struct platform_device *pdev)
.map_irq = of_irq_parse_and_map_pci,
.ops = &gen_pci_ops,
};
+#endif

if (!pci)
return -ENOMEM;
@@ -368,8 +429,24 @@ static int gen_pci_probe(struct platform_device *pdev)
gen_pci_release_of_pci_ranges(pci);
return err;
}
+#ifdef CONFIG_ARM64

+#ifdef CONFIG_PCI_MSI
+ pci->msi_parent = of_parse_phandle(np, "msi-parent", 0);
+ if (!pci->msi_parent) {
+ dev_err(&pdev->dev, "Failed to allocate msi-parent.\n");
+ return -EINVAL;
+ }
+#endif
+
+ if (!gen_scan_root_bus(&pdev->dev, pci->cfg.bus_range.start,
+ &gen_pci_ops, pci, &pci->resources)) {
+ dev_err(&pdev->dev, "failed to enable PCIe ports\n");
+ return -ENODEV;
+ }
+#else
pci_common_init_dev(dev, &hw);
+#endif /* CONFIG_ARM64 */
return 0;
}

--
1.9.3