[105/141] powerpc/pseries: Perform proper max_bus_speed detection

Steven Rostedt
2013-07-03T19:10:29Z

[-- Attachment #1: 0105-powerpc-pseries-Perform-proper-max_bus_speed-detecti.patch --]
[-- Type: text/plain, Size: 4985 bytes --]

3.6.11.6 stable review patch.
If anyone has any objections, please let me know.

------------------

From: Kleber Sacilotto de Souza <klebers@linux.vnet.ibm.com>

[ Upstream commit d82fb31abc46620b7c22758c75707069f2763646 ]

On pseries machines the detection for max_bus_speed should be done
through an OpenFirmware property. This patch adds a function to perform
this detection and a hook to perform dynamic adding of the function only
for pseries. This is done by overwriting the weak
pcibios_root_bridge_prepare function which is called by
pci_create_root_bus().

From: Lucas Kannebley Tavares <lucaskt@linux.vnet.ibm.com>
Signed-off-by: Kleber Sacilotto de Souza <klebers@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
arch/powerpc/include/asm/machdep.h | 3 ++
arch/powerpc/kernel/pci-common.c | 8 +++++
arch/powerpc/platforms/pseries/pci.c | 53 ++++++++++++++++++++++++++++++
arch/powerpc/platforms/pseries/pseries.h | 4 +++
arch/powerpc/platforms/pseries/setup.c | 3 ++
5 files changed, 71 insertions(+)

diff --git a/arch/powerpc/include/asm/machdep.h b/arch/powerpc/include/asm/machdep.h
index 42ce570..fd23013 100644
--- a/arch/powerpc/include/asm/machdep.h
+++ b/arch/powerpc/include/asm/machdep.h
@@ -29,6 +29,7 @@ struct rtc_time;
struct file;
struct pci_controller;
struct kimage;
+struct pci_host_bridge;

struct machdep_calls {
char *name;
@@ -107,6 +108,8 @@ struct machdep_calls {
void (*pcibios_fixup)(void);
int (*pci_probe_mode)(struct pci_bus *);
void (*pci_irq_fixup)(struct pci_dev *dev);
+ int (*pcibios_root_bridge_prepare)(struct pci_host_bridge
+ *bridge);

/* To setup PHBs when using automatic OF platform driver for PCI */
int (*pci_setup_phb)(struct pci_controller *host);
diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c
index 51ecf87..6fe4341 100644
--- a/arch/powerpc/kernel/pci-common.c
+++ b/arch/powerpc/kernel/pci-common.c
@@ -826,6 +826,14 @@ int pci_proc_domain(struct pci_bus *bus)
return 1;
}

+int pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
+{
+ if (ppc_md.pcibios_root_bridge_prepare)
+ return ppc_md.pcibios_root_bridge_prepare(bridge);
+
+ return 0;
+}
+
/* This header fixup will do the resource fixup for all devices as they are
* probed, but not for bridge ranges
*/
diff --git a/arch/powerpc/platforms/pseries/pci.c b/arch/powerpc/platforms/pseries/pci.c
index 2c6ded2..7f6f556 100644
--- a/arch/powerpc/platforms/pseries/pci.c
+++ b/arch/powerpc/platforms/pseries/pci.c
@@ -107,3 +107,56 @@ static void fixup_winbond_82c105(struct pci_dev* dev)
}
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_WINBOND, PCI_DEVICE_ID_WINBOND_82C105,
fixup_winbond_82c105);
+
+int pseries_root_bridge_prepare(struct pci_host_bridge *bridge)
+{
+ struct device_node *dn, *pdn;
+ struct pci_bus *bus;
+ const uint32_t *pcie_link_speed_stats;
+
+ bus = bridge->bus;
+
+ dn = pcibios_get_phb_of_node(bus);
+ if (!dn)
+ return 0;
+
+ for (pdn = dn; pdn != NULL; pdn = of_get_next_parent(pdn)) {
+ pcie_link_speed_stats = (const uint32_t *) of_get_property(pdn,
+ "ibm,pcie-link-speed-stats", NULL);
+ if (pcie_link_speed_stats)
+ break;
+ }
+
+ of_node_put(pdn);
+
+ if (!pcie_link_speed_stats) {
+ pr_err("no ibm,pcie-link-speed-stats property\n");
+ return 0;
+ }
+
+ switch (pcie_link_speed_stats[0]) {
+ case 0x01:
+ bus->max_bus_speed = PCIE_SPEED_2_5GT;
+ break;
+ case 0x02:
+ bus->max_bus_speed = PCIE_SPEED_5_0GT;
+ break;
+ default:
+ bus->max_bus_speed = PCI_SPEED_UNKNOWN;
+ break;
+ }
+
+ switch (pcie_link_speed_stats[1]) {
+ case 0x01:
+ bus->cur_bus_speed = PCIE_SPEED_2_5GT;
+ break;
+ case 0x02:
+ bus->cur_bus_speed = PCIE_SPEED_5_0GT;
+ break;
+ default:
+ bus->cur_bus_speed = PCI_SPEED_UNKNOWN;
+ break;
+ }
+
+ return 0;
+}
diff --git a/arch/powerpc/platforms/pseries/pseries.h b/arch/powerpc/platforms/pseries/pseries.h
index 9a3dda0..b79393d 100644
--- a/arch/powerpc/platforms/pseries/pseries.h
+++ b/arch/powerpc/platforms/pseries/pseries.h
@@ -60,4 +60,8 @@ extern int dlpar_detach_node(struct device_node *);
/* Snooze Delay, pseries_idle */
DECLARE_PER_CPU(long, smt_snooze_delay);

+/* PCI root bridge prepare function override for pseries */
+struct pci_host_bridge;
+int pseries_root_bridge_prepare(struct pci_host_bridge *bridge);
+
#endif /* _PSERIES_PSERIES_H */
diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 51ecac9..5f01342 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -404,6 +404,9 @@ static void __init pSeries_setup_arch(void)
ppc_md.enable_pmcs = pseries_lpar_enable_pmcs;
else
ppc_md.enable_pmcs = power4_enable_pmcs;
+
+ ppc_md.pcibios_root_bridge_prepare = pseries_root_bridge_prepare;
+
}

static int __init pSeries_init_panel(void)
--
1.7.10.4