* [PATCH v6 1/5] x86, pci: add dummy pci device for early stage
2012-11-13 9:07 [PATCH v6 0/5] Reset PCIe devices to address DMA problem on kdump with iommu Takao Indoh
@ 2012-11-13 9:07 ` Takao Indoh
2012-11-13 10:01 ` Andrew Murray
2012-11-13 9:07 ` [PATCH v6 2/5] PCI: Define the maximum number of PCI function Takao Indoh
` (3 subsequent siblings)
4 siblings, 1 reply; 8+ messages in thread
From: Takao Indoh @ 2012-11-13 9:07 UTC (permalink / raw)
To: linux-pci, x86, linux-kernel
Cc: tokunaga.keiich, kexec, hbabu, andi, ddutile, Takao Indoh,
ishii.hironobu, hpa, bhelgaas, tglx, yinghai, mingo, vgoyal,
khalid
From: Yinghai Lu <yinghai@kernel.org>
So we can pass pci_dev *dev to reuse some generic pci functions.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Takao Indoh <indou.takao@jp.fujitsu.com>
---
arch/x86/include/asm/pci-direct.h | 2 +
arch/x86/pci/early.c | 75 +++++++++++++++++++++++++++++++++++++
2 files changed, 77 insertions(+), 0 deletions(-)
diff --git a/arch/x86/include/asm/pci-direct.h b/arch/x86/include/asm/pci-direct.h
index b1e7a45..b6360d3 100644
--- a/arch/x86/include/asm/pci-direct.h
+++ b/arch/x86/include/asm/pci-direct.h
@@ -18,4 +18,6 @@ extern int early_pci_allowed(void);
extern unsigned int pci_early_dump_regs;
extern void early_dump_pci_device(u8 bus, u8 slot, u8 func);
extern void early_dump_pci_devices(void);
+
+struct pci_dev *get_early_pci_dev(int num, int slot, int func);
#endif /* _ASM_X86_PCI_DIRECT_H */
diff --git a/arch/x86/pci/early.c b/arch/x86/pci/early.c
index d1067d5..aea6b2b 100644
--- a/arch/x86/pci/early.c
+++ b/arch/x86/pci/early.c
@@ -109,3 +109,78 @@ void early_dump_pci_devices(void)
}
}
}
+
+static __init int
+early_pci_read(struct pci_bus *bus, unsigned int devfn, int where,
+ int size, u32 *value)
+{
+ int num, slot, func;
+
+ num = bus->number;
+ slot = devfn >> 3;
+ func = devfn & 7;
+ switch (size) {
+ case 1:
+ *value = read_pci_config_byte(num, slot, func, where);
+ break;
+ case 2:
+ *value = read_pci_config_16(num, slot, func, where);
+ break;
+ case 4:
+ *value = read_pci_config(num, slot, func, where);
+ break;
+ }
+
+ return 0;
+}
+
+static __init int
+early_pci_write(struct pci_bus *bus, unsigned int devfn, int where,
+ int size, u32 value)
+{
+ int num, slot, func;
+
+ num = bus->number;
+ slot = devfn >> 3;
+ func = devfn & 7;
+ switch (size) {
+ case 1:
+ write_pci_config_byte(num, slot, func, where, (u8)value);
+ break;
+ case 2:
+ write_pci_config_16(num, slot, func, where, (u16)value);
+ break;
+ case 4:
+ write_pci_config(num, slot, func, where, (u32)value);
+ break;
+ }
+
+ return 0;
+}
+
+static __initdata struct pci_ops pci_early_ops = {
+ .read = early_pci_read,
+ .write = early_pci_write,
+};
+static __initdata struct pci_bus pci_early_bus = {
+ .ops = &pci_early_ops,
+};
+static __initdata char pci_early_init_name[8];
+static __initdata struct pci_dev pci_early_dev = {
+ .bus = &pci_early_bus,
+ .dev = {
+ .init_name = pci_early_init_name,
+ },
+};
+
+__init struct pci_dev *get_early_pci_dev(int num, int slot, int func)
+{
+ struct pci_dev *pdev;
+
+ pdev = &pci_early_dev;
+ pdev->devfn = (slot<<3) | (func & 7);
+ pdev->bus->number = num;
+ sprintf((char *)pdev->dev.init_name, "%02x:%02x.%01x", num, slot, func);
+
+ return pdev;
+}
--
1.7.1
^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH v6 1/5] x86, pci: add dummy pci device for early stage
2012-11-13 9:07 ` [PATCH v6 1/5] x86, pci: add dummy pci device for early stage Takao Indoh
@ 2012-11-13 10:01 ` Andrew Murray
2012-11-13 10:57 ` Takao Indoh
0 siblings, 1 reply; 8+ messages in thread
From: Andrew Murray @ 2012-11-13 10:01 UTC (permalink / raw)
To: Takao Indoh
Cc: linux-pci, x86, linux-kernel, tokunaga.keiich, kexec, hbabu,
andi, ddutile, ishii.hironobu, hpa, bhelgaas, tglx, yinghai,
mingo, vgoyal, khalid
Hello,
Some comments inline...
On 13 November 2012 09:07, Takao Indoh <indou.takao@jp.fujitsu.com> wrote:
> From: Yinghai Lu <yinghai@kernel.org>
>
> So we can pass pci_dev *dev to reuse some generic pci functions.
>
> Signed-off-by: Yinghai Lu <yinghai@kernel.org>
> Signed-off-by: Takao Indoh <indou.takao@jp.fujitsu.com>
> ---
> arch/x86/include/asm/pci-direct.h | 2 +
> arch/x86/pci/early.c | 75 +++++++++++++++++++++++++++++++++++++
> 2 files changed, 77 insertions(+), 0 deletions(-)
>
> diff --git a/arch/x86/include/asm/pci-direct.h b/arch/x86/include/asm/pci-direct.h
> index b1e7a45..b6360d3 100644
> --- a/arch/x86/include/asm/pci-direct.h
> +++ b/arch/x86/include/asm/pci-direct.h
> @@ -18,4 +18,6 @@ extern int early_pci_allowed(void);
> extern unsigned int pci_early_dump_regs;
> extern void early_dump_pci_device(u8 bus, u8 slot, u8 func);
> extern void early_dump_pci_devices(void);
> +
> +struct pci_dev *get_early_pci_dev(int num, int slot, int func);
> #endif /* _ASM_X86_PCI_DIRECT_H */
> diff --git a/arch/x86/pci/early.c b/arch/x86/pci/early.c
> index d1067d5..aea6b2b 100644
> --- a/arch/x86/pci/early.c
> +++ b/arch/x86/pci/early.c
> @@ -109,3 +109,78 @@ void early_dump_pci_devices(void)
> }
> }
> }
> +
> +static __init int
> +early_pci_read(struct pci_bus *bus, unsigned int devfn, int where,
> + int size, u32 *value)
> +{
> + int num, slot, func;
> +
> + num = bus->number;
> + slot = devfn >> 3;
> + func = devfn & 7;
You may want to use the PCI_SLOT and PCI_FUNC macros in
include/linux/pci.h to determine values for slot and func.
> + switch (size) {
> + case 1:
> + *value = read_pci_config_byte(num, slot, func, where);
> + break;
> + case 2:
> + *value = read_pci_config_16(num, slot, func, where);
> + break;
> + case 4:
> + *value = read_pci_config(num, slot, func, where);
> + break;
> + }
> +
> + return 0;
> +}
> +
> +static __init int
> +early_pci_write(struct pci_bus *bus, unsigned int devfn, int where,
> + int size, u32 value)
> +{
> + int num, slot, func;
> +
> + num = bus->number;
> + slot = devfn >> 3;
> + func = devfn & 7;
As above.
> + switch (size) {
> + case 1:
> + write_pci_config_byte(num, slot, func, where, (u8)value);
> + break;
> + case 2:
> + write_pci_config_16(num, slot, func, where, (u16)value);
> + break;
> + case 4:
> + write_pci_config(num, slot, func, where, (u32)value);
> + break;
> + }
> +
> + return 0;
> +}
> +
> +static __initdata struct pci_ops pci_early_ops = {
> + .read = early_pci_read,
> + .write = early_pci_write,
> +};
> +static __initdata struct pci_bus pci_early_bus = {
> + .ops = &pci_early_ops,
> +};
> +static __initdata char pci_early_init_name[8];
> +static __initdata struct pci_dev pci_early_dev = {
> + .bus = &pci_early_bus,
> + .dev = {
> + .init_name = pci_early_init_name,
> + },
> +};
> +
> +__init struct pci_dev *get_early_pci_dev(int num, int slot, int func)
> +{
> + struct pci_dev *pdev;
> +
> + pdev = &pci_early_dev;
> + pdev->devfn = (slot<<3) | (func & 7);
You can use PCI_DEVFN here.
> + pdev->bus->number = num;
> + sprintf((char *)pdev->dev.init_name, "%02x:%02x.%01x", num, slot, func);
> +
> + return pdev;
> +}
> --
> 1.7.1
>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-pci" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
Andrew Murray
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH v6 1/5] x86, pci: add dummy pci device for early stage
2012-11-13 10:01 ` Andrew Murray
@ 2012-11-13 10:57 ` Takao Indoh
0 siblings, 0 replies; 8+ messages in thread
From: Takao Indoh @ 2012-11-13 10:57 UTC (permalink / raw)
To: amurray
Cc: linux-pci, x86, linux-kernel, tokunaga.keiich, kexec, hbabu,
andi, ddutile, ishii.hironobu, hpa, bhelgaas, tglx, yinghai,
mingo, vgoyal, khalid
(2012/11/13 19:01), Andrew Murray wrote:
> Hello,
>
> Some comments inline...
>
> On 13 November 2012 09:07, Takao Indoh <indou.takao@jp.fujitsu.com> wrote:
>> From: Yinghai Lu <yinghai@kernel.org>
>>
>> So we can pass pci_dev *dev to reuse some generic pci functions.
>>
>> Signed-off-by: Yinghai Lu <yinghai@kernel.org>
>> Signed-off-by: Takao Indoh <indou.takao@jp.fujitsu.com>
>> ---
>> arch/x86/include/asm/pci-direct.h | 2 +
>> arch/x86/pci/early.c | 75 +++++++++++++++++++++++++++++++++++++
>> 2 files changed, 77 insertions(+), 0 deletions(-)
>>
>> diff --git a/arch/x86/include/asm/pci-direct.h b/arch/x86/include/asm/pci-direct.h
>> index b1e7a45..b6360d3 100644
>> --- a/arch/x86/include/asm/pci-direct.h
>> +++ b/arch/x86/include/asm/pci-direct.h
>> @@ -18,4 +18,6 @@ extern int early_pci_allowed(void);
>> extern unsigned int pci_early_dump_regs;
>> extern void early_dump_pci_device(u8 bus, u8 slot, u8 func);
>> extern void early_dump_pci_devices(void);
>> +
>> +struct pci_dev *get_early_pci_dev(int num, int slot, int func);
>> #endif /* _ASM_X86_PCI_DIRECT_H */
>> diff --git a/arch/x86/pci/early.c b/arch/x86/pci/early.c
>> index d1067d5..aea6b2b 100644
>> --- a/arch/x86/pci/early.c
>> +++ b/arch/x86/pci/early.c
>> @@ -109,3 +109,78 @@ void early_dump_pci_devices(void)
>> }
>> }
>> }
>> +
>> +static __init int
>> +early_pci_read(struct pci_bus *bus, unsigned int devfn, int where,
>> + int size, u32 *value)
>> +{
>> + int num, slot, func;
>> +
>> + num = bus->number;
>> + slot = devfn >> 3;
>> + func = devfn & 7;
>
> You may want to use the PCI_SLOT and PCI_FUNC macros in
> include/linux/pci.h to determine values for slot and func.
>
>> + switch (size) {
>> + case 1:
>> + *value = read_pci_config_byte(num, slot, func, where);
>> + break;
>> + case 2:
>> + *value = read_pci_config_16(num, slot, func, where);
>> + break;
>> + case 4:
>> + *value = read_pci_config(num, slot, func, where);
>> + break;
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static __init int
>> +early_pci_write(struct pci_bus *bus, unsigned int devfn, int where,
>> + int size, u32 value)
>> +{
>> + int num, slot, func;
>> +
>> + num = bus->number;
>> + slot = devfn >> 3;
>> + func = devfn & 7;
>
> As above.
>
>> + switch (size) {
>> + case 1:
>> + write_pci_config_byte(num, slot, func, where, (u8)value);
>> + break;
>> + case 2:
>> + write_pci_config_16(num, slot, func, where, (u16)value);
>> + break;
>> + case 4:
>> + write_pci_config(num, slot, func, where, (u32)value);
>> + break;
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static __initdata struct pci_ops pci_early_ops = {
>> + .read = early_pci_read,
>> + .write = early_pci_write,
>> +};
>> +static __initdata struct pci_bus pci_early_bus = {
>> + .ops = &pci_early_ops,
>> +};
>> +static __initdata char pci_early_init_name[8];
>> +static __initdata struct pci_dev pci_early_dev = {
>> + .bus = &pci_early_bus,
>> + .dev = {
>> + .init_name = pci_early_init_name,
>> + },
>> +};
>> +
>> +__init struct pci_dev *get_early_pci_dev(int num, int slot, int func)
>> +{
>> + struct pci_dev *pdev;
>> +
>> + pdev = &pci_early_dev;
>> + pdev->devfn = (slot<<3) | (func & 7);
>
> You can use PCI_DEVFN here.
Yeah, I forgot to use these macros. I'll fix them, thanks!
Thanks,
Takao Indoh
>
>> + pdev->bus->number = num;
>> + sprintf((char *)pdev->dev.init_name, "%02x:%02x.%01x", num, slot, func);
>> +
>> + return pdev;
>> +}
>> --
>> 1.7.1
>>
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-pci" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>
> Andrew Murray
>
>
^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH v6 2/5] PCI: Define the maximum number of PCI function
2012-11-13 9:07 [PATCH v6 0/5] Reset PCIe devices to address DMA problem on kdump with iommu Takao Indoh
2012-11-13 9:07 ` [PATCH v6 1/5] x86, pci: add dummy pci device for early stage Takao Indoh
@ 2012-11-13 9:07 ` Takao Indoh
2012-11-13 9:07 ` [PATCH v6 3/5] Make reset_devices available at early stage Takao Indoh
` (2 subsequent siblings)
4 siblings, 0 replies; 8+ messages in thread
From: Takao Indoh @ 2012-11-13 9:07 UTC (permalink / raw)
To: linux-pci, x86, linux-kernel
Cc: tokunaga.keiich, kexec, hbabu, andi, ddutile, vgoyal,
ishii.hironobu, hpa, bhelgaas, tglx, yinghai, mingo, Takao Indoh,
khalid
Define the maximum number of PCI function so that PCI functions can be
enumerated without using "8".
Signed-off-by: Takao Indoh <indou.takao@jp.fujitsu.com>
---
include/linux/pci.h | 2 ++
1 files changed, 2 insertions(+), 0 deletions(-)
diff --git a/include/linux/pci.h b/include/linux/pci.h
index ee21795..eca3231 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -35,6 +35,8 @@
/* Include the ID list */
#include <linux/pci_ids.h>
+#define PCI_MAX_FUNCTIONS 8
+
/* pci_slot represents a physical slot */
struct pci_slot {
struct pci_bus *bus; /* The bus this slot is on */
--
1.7.1
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH v6 3/5] Make reset_devices available at early stage
2012-11-13 9:07 [PATCH v6 0/5] Reset PCIe devices to address DMA problem on kdump with iommu Takao Indoh
2012-11-13 9:07 ` [PATCH v6 1/5] x86, pci: add dummy pci device for early stage Takao Indoh
2012-11-13 9:07 ` [PATCH v6 2/5] PCI: Define the maximum number of PCI function Takao Indoh
@ 2012-11-13 9:07 ` Takao Indoh
2012-11-13 9:08 ` [PATCH v6 4/5] x86, pci: Reset PCIe devices at boot time Takao Indoh
2012-11-13 9:08 ` [PATCH v6 5/5] x86, pci: Enable PCI INTx when MSI is disabled Takao Indoh
4 siblings, 0 replies; 8+ messages in thread
From: Takao Indoh @ 2012-11-13 9:07 UTC (permalink / raw)
To: linux-pci, x86, linux-kernel
Cc: tokunaga.keiich, kexec, hbabu, andi, ddutile, Takao Indoh,
ishii.hironobu, hpa, bhelgaas, tglx, yinghai, mingo, vgoyal,
khalid
Change reset_devices from __setup to early_param so this parameter is
available at early stage.
Signed-off-by: Takao Indoh <indou.takao@jp.fujitsu.com>
---
init/main.c | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/init/main.c b/init/main.c
index e33e09d..f2b24cb 100644
--- a/init/main.c
+++ b/init/main.c
@@ -144,10 +144,10 @@ EXPORT_SYMBOL(reset_devices);
static int __init set_reset_devices(char *str)
{
reset_devices = 1;
- return 1;
+ return 0;
}
-__setup("reset_devices", set_reset_devices);
+early_param("reset_devices", set_reset_devices);
static const char * argv_init[MAX_INIT_ARGS+2] = { "init", NULL, };
const char * envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, };
--
1.7.1
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH v6 4/5] x86, pci: Reset PCIe devices at boot time
2012-11-13 9:07 [PATCH v6 0/5] Reset PCIe devices to address DMA problem on kdump with iommu Takao Indoh
` (2 preceding siblings ...)
2012-11-13 9:07 ` [PATCH v6 3/5] Make reset_devices available at early stage Takao Indoh
@ 2012-11-13 9:08 ` Takao Indoh
2012-11-13 9:08 ` [PATCH v6 5/5] x86, pci: Enable PCI INTx when MSI is disabled Takao Indoh
4 siblings, 0 replies; 8+ messages in thread
From: Takao Indoh @ 2012-11-13 9:08 UTC (permalink / raw)
To: linux-pci, x86, linux-kernel
Cc: tokunaga.keiich, kexec, hbabu, andi, ddutile, vgoyal,
ishii.hironobu, hpa, bhelgaas, tglx, yinghai, mingo, Takao Indoh,
khalid
This patch resets PCIe devices at boot time by hot reset when
"reset_devices" is specified.
Kdump with intel_iommu=on fails becasue ongoing DMA from first kernel
causes DMAR fault when page table of DMAR is initialized while kdump
kernel is booting up. To solve this problem, this patch resets PCIe
devices by hot reset and its DMA is stopped when reset_devices is
specified.
Signed-off-by: Takao Indoh <indou.takao@jp.fujitsu.com>
---
arch/x86/include/asm/pci-direct.h | 1 +
arch/x86/kernel/setup.c | 3 +
arch/x86/pci/early.c | 228 +++++++++++++++++++++++++++++++++++++
3 files changed, 232 insertions(+), 0 deletions(-)
diff --git a/arch/x86/include/asm/pci-direct.h b/arch/x86/include/asm/pci-direct.h
index b6360d3..5620070 100644
--- a/arch/x86/include/asm/pci-direct.h
+++ b/arch/x86/include/asm/pci-direct.h
@@ -18,6 +18,7 @@ extern int early_pci_allowed(void);
extern unsigned int pci_early_dump_regs;
extern void early_dump_pci_device(u8 bus, u8 slot, u8 func);
extern void early_dump_pci_devices(void);
+extern void early_reset_pcie_devices(void);
struct pci_dev *get_early_pci_dev(int num, int slot, int func);
#endif /* _ASM_X86_PCI_DIRECT_H */
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index ca45696..2e7928e 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -1001,6 +1001,9 @@ void __init setup_arch(char **cmdline_p)
generic_apic_probe();
early_quirks();
+#ifdef CONFIG_PCI
+ early_reset_pcie_devices();
+#endif
/*
* Read APIC and some other early information from ACPI tables.
diff --git a/arch/x86/pci/early.c b/arch/x86/pci/early.c
index aea6b2b..32b02c6 100644
--- a/arch/x86/pci/early.c
+++ b/arch/x86/pci/early.c
@@ -1,5 +1,6 @@
#include <linux/kernel.h>
#include <linux/pci.h>
+#include <linux/bootmem.h>
#include <asm/pci-direct.h>
#include <asm/io.h>
#include <asm/pci_x86.h>
@@ -184,3 +185,230 @@ __init struct pci_dev *get_early_pci_dev(int num, int slot, int func)
return pdev;
}
+
+struct save_config {
+ u32 pci[16];
+ u16 pcie[7];
+ int saved;
+};
+
+struct pcie_port {
+ struct list_head dev;
+ u8 bus;
+ u8 slot;
+ u8 func;
+ u8 secondary;
+ struct save_config save[PCI_MAX_FUNCTIONS];
+};
+
+static __initdata LIST_HEAD(device_list);
+static void __init early_udelay(int loops)
+{
+ while (loops--) {
+ /* Approximately 1 us */
+ native_io_delay();
+ }
+}
+
+struct pci_dev * __init early_pci_dev_init(int bus, int slot, int func)
+{
+ u16 vendor;
+ u8 type;
+ struct pci_dev *pdev;
+
+ pdev = get_early_pci_dev(bus, slot, func);
+ pci_read_config_word(pdev, PCI_VENDOR_ID, &vendor);
+ if (vendor == 0xffff)
+ return NULL;
+
+ pci_read_config_byte(pdev, PCI_HEADER_TYPE, &type);
+ pdev->hdr_type = type;
+ set_pcie_port_type(pdev);
+
+ return pdev;
+}
+
+static void __init do_reset(u8 bus, u8 slot, u8 func)
+{
+ u16 ctrl;
+ struct pci_dev *dev;
+
+ dev = get_early_pci_dev(bus, slot, func);
+ printk(KERN_INFO "pci 0000:%02x:%02x.%d reset\n", bus, slot, func);
+
+ /* Assert Secondary Bus Reset */
+ pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &ctrl);
+ ctrl |= PCI_BRIDGE_CTL_BUS_RESET;
+ pci_write_config_word(dev, PCI_BRIDGE_CONTROL, ctrl);
+
+ /*
+ * PCIe spec requires software to ensure a minimum reset duration
+ * (Trst == 1ms). We have here 5ms safety margin because early_udelay
+ * is not precise.
+ */
+ early_udelay(5000);
+
+ /* De-assert Secondary Bus Reset */
+ ctrl &= ~PCI_BRIDGE_CTL_BUS_RESET;
+ pci_write_config_word(dev, PCI_BRIDGE_CONTROL, ctrl);
+}
+
+static void __init save_state(unsigned bus, unsigned slot, unsigned func,
+ struct save_config *save)
+{
+ struct pci_dev *dev;
+ int i;
+
+ dev = get_early_pci_dev(bus, slot, func);
+ printk(KERN_INFO "pci 0000:%02x:%02x.%d save state\n", bus, slot, func);
+
+ for (i = 0; i < 16; i++)
+ pci_read_config_dword(dev, i * 4, save->pci + i);
+ i = 0;
+ pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &save->pcie[i++]);
+ pcie_capability_read_word(dev, PCI_EXP_LNKCTL, &save->pcie[i++]);
+ pcie_capability_read_word(dev, PCI_EXP_SLTCTL, &save->pcie[i++]);
+ pcie_capability_read_word(dev, PCI_EXP_RTCTL, &save->pcie[i++]);
+ pcie_capability_read_word(dev, PCI_EXP_DEVCTL2, &save->pcie[i++]);
+ pcie_capability_read_word(dev, PCI_EXP_LNKCTL2, &save->pcie[i++]);
+ pcie_capability_read_word(dev, PCI_EXP_SLTCTL2, &save->pcie[i++]);
+
+ save->saved = true;
+}
+
+static void __init restore_state(unsigned bus, unsigned slot, unsigned func,
+ struct save_config *save)
+{
+ struct pci_dev *dev;
+ int i = 0;
+
+ dev = get_early_pci_dev(bus, slot, func);
+ printk(KERN_INFO "pci 0000:%02x:%02x.%d restore state\n",
+ bus, slot, func);
+
+ pcie_capability_write_word(dev, PCI_EXP_DEVCTL, save->pcie[i++]);
+ pcie_capability_write_word(dev, PCI_EXP_LNKCTL, save->pcie[i++]);
+ pcie_capability_write_word(dev, PCI_EXP_SLTCTL, save->pcie[i++]);
+ pcie_capability_write_word(dev, PCI_EXP_RTCTL, save->pcie[i++]);
+ pcie_capability_write_word(dev, PCI_EXP_DEVCTL2, save->pcie[i++]);
+ pcie_capability_write_word(dev, PCI_EXP_LNKCTL2, save->pcie[i++]);
+ pcie_capability_write_word(dev, PCI_EXP_SLTCTL2, save->pcie[i++]);
+
+ for (i = 15; i >= 0; i--)
+ pci_write_config_dword(dev, i * 4, save->pci[i]);
+}
+
+static void __init find_pcie_device(unsigned bus, unsigned slot, unsigned func)
+{
+ struct pci_dev *dev;
+ int f, pcie_type, count;
+ u8 secondary;
+ u32 class;
+ struct pcie_port *port;
+ int children[PCI_MAX_FUNCTIONS];
+
+ dev = early_pci_dev_init(bus, slot, func);
+ if (!dev || !pci_is_pcie(dev))
+ return;
+
+ pcie_type = pci_pcie_type(dev);
+ if ((pcie_type != PCI_EXP_TYPE_ROOT_PORT) &&
+ (pcie_type != PCI_EXP_TYPE_DOWNSTREAM))
+ return;
+
+ if ((dev->hdr_type & 0x7f) != PCI_HEADER_TYPE_BRIDGE)
+ return;
+ pci_read_config_byte(dev, PCI_SECONDARY_BUS, &secondary);
+
+ memset(children, 0, sizeof(children));
+ for (count = 0, f = 0; f < PCI_MAX_FUNCTIONS; f++) {
+ dev = early_pci_dev_init(secondary, 0, f);
+ if (!dev || !pci_is_pcie(dev))
+ continue;
+
+ pcie_type = pci_pcie_type(dev);
+ if ((pcie_type == PCI_EXP_TYPE_UPSTREAM) ||
+ (pcie_type == PCI_EXP_TYPE_PCI_BRIDGE))
+ /* Don't reset switch, bridge */
+ return;
+
+ pci_read_config_dword(dev, PCI_CLASS_REVISION, &class);
+ if ((class >> 24) == PCI_BASE_CLASS_DISPLAY)
+ /* Don't reset VGA device */
+ return;
+
+ count++;
+ children[f] = 1;
+ }
+
+ if (!count)
+ return;
+
+ port = (struct pcie_port *)alloc_bootmem(sizeof(struct pcie_port));
+ if (port == NULL) {
+ printk(KERN_ERR "pci 0000:%02x:%02x.%d alloc_bootmem failed\n",
+ bus, slot, func);
+ return;
+ }
+ memset(port, 0, sizeof(*port));
+ port->bus = bus;
+ port->slot = slot;
+ port->func = func;
+ port->secondary = secondary;
+ for (f = 0; f < PCI_MAX_FUNCTIONS; f++)
+ if (children[f])
+ save_state(secondary, 0, f, &port->save[f]);
+ list_add_tail(&port->dev, &device_list);
+}
+
+void __init early_reset_pcie_devices(void)
+{
+ unsigned bus, slot, func;
+ struct pcie_port *port, *tmp;
+ struct pci_dev *dev;
+
+ if (!early_pci_allowed() || !reset_devices)
+ return;
+
+ /* Find PCIe port and save config registers of its downstream devices */
+ for (bus = 0; bus < 256; bus++) {
+ for (slot = 0; slot < 32; slot++) {
+ for (func = 0; func < PCI_MAX_FUNCTIONS; func++) {
+ u8 type;
+
+ dev = early_pci_dev_init(bus, slot, func);
+ if (!dev)
+ continue;
+
+ type = dev->hdr_type;
+ find_pcie_device(bus, slot, func);
+
+ if ((func == 0) && !(type & 0x80))
+ break;
+ }
+ }
+ }
+
+ if (list_empty(&device_list))
+ return;
+
+ /* Do bus reset */
+ list_for_each_entry(port, &device_list, dev)
+ do_reset(port->bus, port->slot, port->func);
+
+ /*
+ * According to PCIe spec, software must wait a minimum of 100 ms
+ * before sending a configuration request. We have 500ms safety margin
+ * here.
+ */
+ early_udelay(500000);
+
+ /* Restore config registers and free memory */
+ list_for_each_entry_safe(port, tmp, &device_list, dev) {
+ for (func = 0; func < PCI_MAX_FUNCTIONS; func++)
+ if (port->save[func].saved)
+ restore_state(port->secondary, 0, func,
+ &port->save[func]);
+ free_bootmem(__pa(port), sizeof(*port));
+ }
+}
--
1.7.1
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH v6 5/5] x86, pci: Enable PCI INTx when MSI is disabled
2012-11-13 9:07 [PATCH v6 0/5] Reset PCIe devices to address DMA problem on kdump with iommu Takao Indoh
` (3 preceding siblings ...)
2012-11-13 9:08 ` [PATCH v6 4/5] x86, pci: Reset PCIe devices at boot time Takao Indoh
@ 2012-11-13 9:08 ` Takao Indoh
4 siblings, 0 replies; 8+ messages in thread
From: Takao Indoh @ 2012-11-13 9:08 UTC (permalink / raw)
To: linux-pci, x86, linux-kernel
Cc: tokunaga.keiich, kexec, hbabu, andi, ddutile, Takao Indoh,
ishii.hironobu, hpa, bhelgaas, tglx, yinghai, mingo, vgoyal,
khalid
This patch enables INTx if MSI is disabled in pcibios_enable_device().
In normal case interrupt disable bit in command register is 0b on boot
time, but in case of kdump, this bit may be 1b. It causes problems of
some drivers. At leaset I confirmed mptsas driver does not work in such
a case. This patch fix this problem.
Signed-off-by: Takao Indoh <indou.takao@jp.fujitsu.com>
---
arch/x86/pci/common.c | 4 +++-
1 files changed, 3 insertions(+), 1 deletions(-)
diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c
index 720e973..2bb7ecc 100644
--- a/arch/x86/pci/common.c
+++ b/arch/x86/pci/common.c
@@ -615,8 +615,10 @@ int pcibios_enable_device(struct pci_dev *dev, int mask)
if ((err = pci_enable_resources(dev, mask)) < 0)
return err;
- if (!pci_dev_msi_enabled(dev))
+ if (!pci_dev_msi_enabled(dev)) {
+ pci_intx(dev, true);
return pcibios_enable_irq(dev);
+ }
return 0;
}
--
1.7.1
^ permalink raw reply related [flat|nested] 8+ messages in thread