Patchwork Make PCIe hotplug work with Freescale PCIe controllers

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Submitter Rojhalat Ibrahim
Date March 11, 2013, 2:47 p.m.
Message ID <3989200.gO920IVs04@pcimr>
Download mbox | patch
Permalink /patch/226569/
State Superseded
Delegated to: Kumar Gala
Headers show

Comments

Rojhalat Ibrahim - March 11, 2013, 2:47 p.m.
Hi,

this issue was brought up before. 
See this thread: https://lists.ozlabs.org/pipermail/linuxppc-dev/2012-July/099529.html

The following patch works for me.
Hot-added devices appear after "echo 1 > /sys/bus/pci/rescan".
I tested it with a P5020DS development system.

Signed-off-by: Rojhalat Ibrahim <imr@rtschenk.de>
---
 arch/powerpc/sysdev/indirect_pci.c |   53 ++++++++++++++++++++++++++++++-------
 1 file changed, 44 insertions(+), 9 deletions(-)
Joakim Tjernlund - March 11, 2013, 3:17 p.m.
Rojhalat Ibrahim <imr@rtschenk.de> wrote on 2013/03/11 15:47:30:
> 
> Hi,
> 
> this issue was brought up before. 
> See this thread: 
https://lists.ozlabs.org/pipermail/linuxppc-dev/2012-July/099529.html
> 
> The following patch works for me.
> Hot-added devices appear after "echo 1 > /sys/bus/pci/rescan".
> I tested it with a P5020DS development system.
> 
> Signed-off-by: Rojhalat Ibrahim <imr@rtschenk.de>

Nice! This LOOKS ok to me(cannot test ATM as I am lagging behind)

 Jocke

> ---
>  arch/powerpc/sysdev/indirect_pci.c |   53 
++++++++++++++++++++++++++++++-------
>  1 file changed, 44 insertions(+), 9 deletions(-)
> 
> diff --git a/arch/powerpc/sysdev/indirect_pci.c 
b/arch/powerpc/sysdev/indirect_pci.c
> index 82fdad8..aa36009 100644
> --- a/arch/powerpc/sysdev/indirect_pci.c
> +++ b/arch/powerpc/sysdev/indirect_pci.c
> @@ -20,22 +20,19 @@
>  #include <asm/pci-bridge.h>
>  #include <asm/machdep.h>
> 
> +#ifdef CONFIG_FSL_PCI
> +#include <sysdev/fsl_pci.h>
> +#endif
> +
>  static int
> -indirect_read_config(struct pci_bus *bus, unsigned int devfn, int 
offset,
> -           int len, u32 *val)
> +read_config_no_link_check(struct pci_bus *bus, unsigned int devfn, int 
offset,
> +           int len, u32 *val)
>  {
>     struct pci_controller *hose = pci_bus_to_host(bus);
>     volatile void __iomem *cfg_data;
>     u8 cfg_type = 0;
>     u32 bus_no, reg;
> 
> -   if (hose->indirect_type & PPC_INDIRECT_TYPE_NO_PCIE_LINK) {
> -      if (bus->number != hose->first_busno)
> -         return PCIBIOS_DEVICE_NOT_FOUND;
> -      if (devfn != 0)
> -         return PCIBIOS_DEVICE_NOT_FOUND;
> -   }
> -
>     if (ppc_md.pci_exclude_device)
>        if (ppc_md.pci_exclude_device(hose, bus->number, devfn))
>           return PCIBIOS_DEVICE_NOT_FOUND;
> @@ -78,6 +75,44 @@ indirect_read_config(struct pci_bus *bus, unsigned 
int 
> devfn, int offset,
>     return PCIBIOS_SUCCESSFUL;
>  }
> 
> +#ifdef CONFIG_FSL_PCI
> +static int fsl_pcie_check_link(struct pci_bus *bus)
> +{
> +   struct pci_controller *hose = pci_bus_to_host(bus);
> +   u32 val = 0;
> +
> +   read_config_no_link_check(bus, 0, PCIE_LTSSM, 4, &val);
> +   if (val < PCIE_LTSSM_L0) {
> +      hose->indirect_type |= PPC_INDIRECT_TYPE_NO_PCIE_LINK;
> +      return 1;
> +   } else {
> +      hose->indirect_type &= ~PPC_INDIRECT_TYPE_NO_PCIE_LINK;
> +      return 0;
> +   }
> +}
> +#endif
> +
> +static int
> +indirect_read_config(struct pci_bus *bus, unsigned int devfn, int 
offset,
> +           int len, u32 *val)
> +{
> +   struct pci_controller *hose = pci_bus_to_host(bus);
> +
> +#ifdef CONFIG_FSL_PCI
> +   if ((bus->number == hose->first_busno) && (devfn == 0)) {
> +      fsl_pcie_check_link(bus);
> +   }
> +#endif
> +   if (hose->indirect_type & PPC_INDIRECT_TYPE_NO_PCIE_LINK) {
> +      if (bus->number != hose->first_busno)
> +         return PCIBIOS_DEVICE_NOT_FOUND;
> +      if (devfn != 0)
> +         return PCIBIOS_DEVICE_NOT_FOUND;
> +   }
> +
> +   return read_config_no_link_check(bus, devfn, offset, len, val);
> +}
> +
>  static int
>  indirect_write_config(struct pci_bus *bus, unsigned int devfn, int 
offset,
>              int len, u32 val)
>
Kumar Gala - March 11, 2013, 5:17 p.m.
On Mar 11, 2013, at 9:47 AM, Rojhalat Ibrahim wrote:

> Hi,
> 
> this issue was brought up before. 
> See this thread: https://lists.ozlabs.org/pipermail/linuxppc-dev/2012-July/099529.html
> 
> The following patch works for me.
> Hot-added devices appear after "echo 1 > /sys/bus/pci/rescan".
> I tested it with a P5020DS development system.
> 
> Signed-off-by: Rojhalat Ibrahim <imr@rtschenk.de>
> ---
> arch/powerpc/sysdev/indirect_pci.c |   53 ++++++++++++++++++++++++++++++-------
> 1 file changed, 44 insertions(+), 9 deletions(-)

Rather than do it this way, we should do something like:

fsl_indirect_read_config() {
	link check
	if (link)
		indirect_read_config()
}

and just add fsl_indirect_{r,w}_config into fsl_pci.c

- k

> 
> diff --git a/arch/powerpc/sysdev/indirect_pci.c b/arch/powerpc/sysdev/indirect_pci.c
> index 82fdad8..aa36009 100644
> --- a/arch/powerpc/sysdev/indirect_pci.c
> +++ b/arch/powerpc/sysdev/indirect_pci.c
> @@ -20,22 +20,19 @@
> #include <asm/pci-bridge.h>
> #include <asm/machdep.h>
> 
> +#ifdef CONFIG_FSL_PCI
> +#include <sysdev/fsl_pci.h>
> +#endif
> +
> static int
> -indirect_read_config(struct pci_bus *bus, unsigned int devfn, int offset,
> -		     int len, u32 *val)
> +read_config_no_link_check(struct pci_bus *bus, unsigned int devfn, int offset,
> +			  int len, u32 *val)
> {
> 	struct pci_controller *hose = pci_bus_to_host(bus);
> 	volatile void __iomem *cfg_data;
> 	u8 cfg_type = 0;
> 	u32 bus_no, reg;
> 
> -	if (hose->indirect_type & PPC_INDIRECT_TYPE_NO_PCIE_LINK) {
> -		if (bus->number != hose->first_busno)
> -			return PCIBIOS_DEVICE_NOT_FOUND;
> -		if (devfn != 0)
> -			return PCIBIOS_DEVICE_NOT_FOUND;
> -	}
> -
> 	if (ppc_md.pci_exclude_device)
> 		if (ppc_md.pci_exclude_device(hose, bus->number, devfn))
> 			return PCIBIOS_DEVICE_NOT_FOUND;
> @@ -78,6 +75,44 @@ indirect_read_config(struct pci_bus *bus, unsigned int devfn, int offset,
> 	return PCIBIOS_SUCCESSFUL;
> }
> 
> +#ifdef CONFIG_FSL_PCI
> +static int fsl_pcie_check_link(struct pci_bus *bus)
> +{
> +	struct pci_controller *hose = pci_bus_to_host(bus);
> +	u32 val = 0;
> +
> +	read_config_no_link_check(bus, 0, PCIE_LTSSM, 4, &val);
> +	if (val < PCIE_LTSSM_L0) {
> +		hose->indirect_type |= PPC_INDIRECT_TYPE_NO_PCIE_LINK;
> +		return 1;
> +	} else {
> +		hose->indirect_type &= ~PPC_INDIRECT_TYPE_NO_PCIE_LINK;
> +		return 0;
> +	}
> +}
> +#endif
> +
> +static int
> +indirect_read_config(struct pci_bus *bus, unsigned int devfn, int offset,
> +		     int len, u32 *val)
> +{
> +	struct pci_controller *hose = pci_bus_to_host(bus);
> +
> +#ifdef CONFIG_FSL_PCI
> +	if ((bus->number == hose->first_busno) && (devfn == 0)) {
> +		fsl_pcie_check_link(bus);
> +	}
> +#endif
> +	if (hose->indirect_type & PPC_INDIRECT_TYPE_NO_PCIE_LINK) {
> +		if (bus->number != hose->first_busno)
> +			return PCIBIOS_DEVICE_NOT_FOUND;
> +		if (devfn != 0)
> +			return PCIBIOS_DEVICE_NOT_FOUND;
> +	}
> +
> +	return read_config_no_link_check(bus, devfn, offset, len, val);
> +}
> +
> static int
> indirect_write_config(struct pci_bus *bus, unsigned int devfn, int offset,
> 		      int len, u32 val)

Patch

diff --git a/arch/powerpc/sysdev/indirect_pci.c b/arch/powerpc/sysdev/indirect_pci.c
index 82fdad8..aa36009 100644
--- a/arch/powerpc/sysdev/indirect_pci.c
+++ b/arch/powerpc/sysdev/indirect_pci.c
@@ -20,22 +20,19 @@ 
 #include <asm/pci-bridge.h>
 #include <asm/machdep.h>
 
+#ifdef CONFIG_FSL_PCI
+#include <sysdev/fsl_pci.h>
+#endif
+
 static int
-indirect_read_config(struct pci_bus *bus, unsigned int devfn, int offset,
-		     int len, u32 *val)
+read_config_no_link_check(struct pci_bus *bus, unsigned int devfn, int offset,
+			  int len, u32 *val)
 {
 	struct pci_controller *hose = pci_bus_to_host(bus);
 	volatile void __iomem *cfg_data;
 	u8 cfg_type = 0;
 	u32 bus_no, reg;
 
-	if (hose->indirect_type & PPC_INDIRECT_TYPE_NO_PCIE_LINK) {
-		if (bus->number != hose->first_busno)
-			return PCIBIOS_DEVICE_NOT_FOUND;
-		if (devfn != 0)
-			return PCIBIOS_DEVICE_NOT_FOUND;
-	}
-
 	if (ppc_md.pci_exclude_device)
 		if (ppc_md.pci_exclude_device(hose, bus->number, devfn))
 			return PCIBIOS_DEVICE_NOT_FOUND;
@@ -78,6 +75,44 @@  indirect_read_config(struct pci_bus *bus, unsigned int devfn, int offset,
 	return PCIBIOS_SUCCESSFUL;
 }
 
+#ifdef CONFIG_FSL_PCI
+static int fsl_pcie_check_link(struct pci_bus *bus)
+{
+	struct pci_controller *hose = pci_bus_to_host(bus);
+	u32 val = 0;
+
+	read_config_no_link_check(bus, 0, PCIE_LTSSM, 4, &val);
+	if (val < PCIE_LTSSM_L0) {
+		hose->indirect_type |= PPC_INDIRECT_TYPE_NO_PCIE_LINK;
+		return 1;
+	} else {
+		hose->indirect_type &= ~PPC_INDIRECT_TYPE_NO_PCIE_LINK;
+		return 0;
+	}
+}
+#endif
+
+static int
+indirect_read_config(struct pci_bus *bus, unsigned int devfn, int offset,
+		     int len, u32 *val)
+{
+	struct pci_controller *hose = pci_bus_to_host(bus);
+
+#ifdef CONFIG_FSL_PCI
+	if ((bus->number == hose->first_busno) && (devfn == 0)) {
+		fsl_pcie_check_link(bus);
+	}
+#endif
+	if (hose->indirect_type & PPC_INDIRECT_TYPE_NO_PCIE_LINK) {
+		if (bus->number != hose->first_busno)
+			return PCIBIOS_DEVICE_NOT_FOUND;
+		if (devfn != 0)
+			return PCIBIOS_DEVICE_NOT_FOUND;
+	}
+
+	return read_config_no_link_check(bus, devfn, offset, len, val);
+}
+
 static int
 indirect_write_config(struct pci_bus *bus, unsigned int devfn, int offset,
 		      int len, u32 val)