On Apr 3, 2013, at 2:09 AM, Rojhalat Ibrahim wrote:

Hi Kumar,
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what about this patch? Any reasons not to apply?
=20
  Rojhalat

Was on vacation, getting back to it now.  Do send a proper patch =
w/commit message & signed-off-by.

- k

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=20
On Monday 18 March 2013 10:22:40 Rojhalat Ibrahim wrote:

quoted

On Thursday 14 March 2013 15:35:40 Kumar Gala wrote:

quoted

On Mar 14, 2013, at 4:43 AM, Rojhalat Ibrahim wrote:

quoted

On Wednesday 13 March 2013 14:07:16 Kumar Gala wrote:

quoted

diff --git a/arch/powerpc/sysdev/fsl_pci.c

b/arch/powerpc/sysdev/fsl_pci.c
index 41bbcc4..b18c377 100644

--- a/arch/powerpc/sysdev/fsl_pci.c
+++ b/arch/powerpc/sysdev/fsl_pci.c

@@ -74,6 +74,35 @@ static int __init fsl_pcie_check_link(struct

pci_controller *hose) return 0;
}
=20
+static int fsl_indirect_read_config(struct pci_bus *bus, unsigned =

int

quoted

quoted

quoted

quoted

devfn, +				    int offset, int len, u32 =

*val)

quoted

quoted

quoted

quoted

+{
+	struct pci_controller *hose =3D pci_bus_to_host(bus);
+
+	/* check the link status */
+	if ((bus->number =3D=3D hose->first_busno) && (devfn =3D=3D 0)) =

{

quoted

quoted

quoted

quoted

+		if (fsl_pcie_check_link(hose))
+			hose->indirect_type |=3D =

PPC_INDIRECT_TYPE_NO_PCIE_LINK;

quoted

quoted

quoted

quoted

+		else
+			hose->indirect_type &=3D =

~PPC_INDIRECT_TYPE_NO_PCIE_LINK;

quoted

quoted

quoted

quoted

+	}
+	return indirect_read_config(bus, devfn, offset, len, val);
+}
+

=20
This does not work because fsl_indirect_read_config calls
fsl_pcie_check_link which calls early_read_config_dword which =

eventually

quoted

quoted

quoted

calls fsl_indirect_read_config, so the kernel hangs in a recursion =

loop.

quoted

quoted

quoted

Below is a modified patch that does work.

=20
ok, that makes sense, but I guess now its making me question the =

following=20

statement:

quoted

quoted

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if ((bus->number =3D=3D hose->first_busno) && (devfn =3D=3D 0)) {

=20
Why do we have this conditional?
=20
- k

=20
Right. This is not necessary anymore. I modified the patch =

accordingly.

quoted

=20
=20
Signed-off-by: Rojhalat Ibrahim <redacted>
---
arch/powerpc/include/asm/pci-bridge.h |    6 ++++
arch/powerpc/sysdev/fsl_pci.c         |   51
+++++++++++++++++++++++++++++----- arch/powerpc/sysdev/indirect_pci.c =

   |=20

quoted

10 ++----
3 files changed, 54 insertions(+), 13 deletions(-)
=20

diff --git a/arch/powerpc/include/asm/pci-bridge.h

b/arch/powerpc/include/asm/pci-bridge.h index c0278f0..ffbc5fd 100644

--- a/arch/powerpc/include/asm/pci-bridge.h
+++ b/arch/powerpc/include/asm/pci-bridge.h

@@ -120,6 +120,12 @@ extern void setup_indirect_pci(struct =

pci_controller*

quoted

hose, resource_size_t cfg_addr,
			       resource_size_t cfg_data, u32 flags);
=20
+extern int indirect_read_config(struct pci_bus *bus, unsigned int =

devfn,

quoted

+				int offset, int len, u32 *val);
+
+extern int indirect_write_config(struct pci_bus *bus, unsigned int =

devfn,

quoted

+				 int offset, int len, u32 val);
+
static inline struct pci_controller *pci_bus_to_host(const struct =

pci_bus

quoted

*bus) {
	return bus->sysdata;

diff --git a/arch/powerpc/sysdev/fsl_pci.c =

b/arch/powerpc/sysdev/fsl_pci.c

quoted

index 41bbcc4..9c0fcc9 100644

--- a/arch/powerpc/sysdev/fsl_pci.c
+++ b/arch/powerpc/sysdev/fsl_pci.c

@@ -54,12 +54,22 @@ static void quirk_fsl_pcie_header(struct pci_dev =

*dev)

quoted

	return;
}
=20
-static int __init fsl_pcie_check_link(struct pci_controller *hose)
+static int fsl_indirect_read_config(struct pci_bus *, unsigned int,
+				    int, int, u32 *);
+
+static int fsl_pcie_check_link(struct pci_controller *hose)
{
-	u32 val;
+	u32 val =3D 0;
=20
	if (hose->indirect_type & PPC_INDIRECT_TYPE_FSL_CFG_REG_LINK) {
-		early_read_config_dword(hose, 0, 0, PCIE_LTSSM, &val);
+		if (hose->ops->read =3D=3D fsl_indirect_read_config) {
+			struct pci_bus bus;
+			bus.number =3D 0;
+			bus.sysdata =3D hose;
+			bus.ops =3D hose->ops;
+			indirect_read_config(&bus, 0, PCIE_LTSSM, 4, =

&val);

quoted

+		} else
+			early_read_config_dword(hose, 0, 0, PCIE_LTSSM, =

&val);

quoted

		if (val < PCIE_LTSSM_L0)
			return 1;
	} else {

@@ -74,6 +84,33 @@ static int __init fsl_pcie_check_link(struct

pci_controller *hose) return 0;
}
=20
+static int fsl_indirect_read_config(struct pci_bus *bus, unsigned =

int

quoted

devfn, +				    int offset, int len, u32 =

*val)

quoted

+{
+	struct pci_controller *hose =3D pci_bus_to_host(bus);
+
+	if (fsl_pcie_check_link(hose))
+		hose->indirect_type |=3D PPC_INDIRECT_TYPE_NO_PCIE_LINK;
+	else
+		hose->indirect_type &=3D =

~PPC_INDIRECT_TYPE_NO_PCIE_LINK;

quoted

+
+	return indirect_read_config(bus, devfn, offset, len, val);
+}
+
+static struct pci_ops fsl_indirect_pci_ops =3D
+{
+	.read =3D fsl_indirect_read_config,
+	.write =3D indirect_write_config,
+};
+
+static void __init fsl_setup_indirect_pci(struct pci_controller* =

hose,

quoted

+					  resource_size_t cfg_addr,
+					  resource_size_t cfg_data, u32 =

flags)

quoted

+{
+	setup_indirect_pci(hose, cfg_addr, cfg_data, flags);
+	hose->ops =3D &fsl_indirect_pci_ops;
+}
+
#if defined(CONFIG_FSL_SOC_BOOKE) || defined(CONFIG_PPC_86xx)
=20
#define MAX_PHYS_ADDR_BITS	40

@@ -469,8 +506,8 @@ int __init fsl_add_bridge(struct platform_device =

*pdev,

quoted

int is_primary) if (!hose->private_data)
		goto no_bridge;
=20
-	setup_indirect_pci(hose, rsrc.start, rsrc.start + 0x4,
-		PPC_INDIRECT_TYPE_BIG_ENDIAN);
+	fsl_setup_indirect_pci(hose, rsrc.start, rsrc.start + 0x4,
+			       PPC_INDIRECT_TYPE_BIG_ENDIAN);
=20
	if (in_be32(&pci->block_rev1) < PCIE_IP_REV_3_0)
		hose->indirect_type |=3D =

PPC_INDIRECT_TYPE_FSL_CFG_REG_LINK;

quoted

@@ -779,8 +816,8 @@ int __init mpc83xx_add_bridge(struct device_node =

*dev)

quoted

		if (ret)
			goto err0;
	} else {
-		setup_indirect_pci(hose, rsrc_cfg.start,
-				   rsrc_cfg.start + 4, 0);
+		fsl_setup_indirect_pci(hose, rsrc_cfg.start,
+				       rsrc_cfg.start + 4, 0);
	}
=20
	printk(KERN_INFO "Found FSL PCI host bridge at 0x%016llx. "

diff --git a/arch/powerpc/sysdev/indirect_pci.c

b/arch/powerpc/sysdev/indirect_pci.c index 82fdad8..c6c8b52 100644

--- a/arch/powerpc/sysdev/indirect_pci.c
+++ b/arch/powerpc/sysdev/indirect_pci.c

@@ -20,9 +20,8 @@

#include <asm/pci-bridge.h>
#include <asm/machdep.h>
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-static int
-indirect_read_config(struct pci_bus *bus, unsigned int devfn, int =

offset,

quoted

-		     int len, u32 *val)
+int indirect_read_config(struct pci_bus *bus, unsigned int devfn,
+			 int offset, int len, u32 *val)
{
	struct pci_controller *hose =3D pci_bus_to_host(bus);
	volatile void __iomem *cfg_data;

@@ -78,9 +77,8 @@ indirect_read_config(struct pci_bus *bus, unsigned =

int

quoted

devfn, int offset, return PCIBIOS_SUCCESSFUL;
}
=20
-static int
-indirect_write_config(struct pci_bus *bus, unsigned int devfn, int =

offset,

quoted

-		      int len, u32 val)
+int indirect_write_config(struct pci_bus *bus, unsigned int devfn,
+			  int offset, int len, u32 val)
{
	struct pci_controller *hose =3D pci_bus_to_host(bus);
	volatile void __iomem *cfg_data;
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