This is the latest patch for PCI recovery.
(merge Grant's text, fix spellmisses)
Signed-off-by: Hidetoshi Seto <[email protected]>
diff -Nur linux-2.6.8.1/arch/i386/pci/common.c linux-2.6.8.1-pci/arch/i386/pci/common.c
--- linux-2.6.8.1/arch/i386/pci/common.c 2004-08-14 19:55:19.000000000 +0900
+++ linux-2.6.8.1-pci/arch/i386/pci/common.c 2004-09-13 10:44:53.000000000 +0900
@@ -118,6 +118,19 @@
pci_read_bridge_bases(b);
}
+#ifdef CONFIG_PCI_ERROR_RECOVERY
+static void pci_i386_fixup_host_bridge_self(struct pci_bus *bus)
+{
+ struct pci_dev *pdev;
+
+ list_for_each_entry(pdev, &bus->devices, bus_list) {
+ if (pdev->class >> 8 == PCI_CLASS_BRIDGE_HOST) {
+ bus->self = pdev;
+ return;
+ }
+ }
+}
+#endif
struct pci_bus * __devinit pcibios_scan_root(int busnum)
{
@@ -132,7 +145,16 @@
printk("PCI: Probing PCI hardware (bus %02x)\n", busnum);
+#ifdef CONFIG_PCI_ERROR_RECOVERY
+{
+ struct pci_bus *bus = pci_scan_bus(busnum, &pci_root_ops, NULL);
+ if (bus)
+ pci_i386_fixup_host_bridge_self(bus);
+ return bus;
+}
+#else
return pci_scan_bus(busnum, &pci_root_ops, NULL);
+#endif
}
extern u8 pci_cache_line_size;
diff -Nur linux-2.6.8.1/drivers/pci/Kconfig linux-2.6.8.1-pci/drivers/pci/Kconfig
--- linux-2.6.8.1/drivers/pci/Kconfig 2004-08-14 19:55:09.000000000 +0900
+++ linux-2.6.8.1-pci/drivers/pci/Kconfig 2004-09-13 11:02:37.000000000 +0900
@@ -47,3 +47,11 @@
When in doubt, say Y.
+config PCI_ERROR_RECOVERY
+ bool "PCI device error recovery"
+ depends on PCI && EXPERIMENTAL
+ ---help---
+ Saying Y provides PCI infrastructure to recover from some PCI errors.
+ Currently, very few PCI drivers actually implement this.
+ See Documentation/pci-errors.txt for a description of the
+ infrastructure provided.
diff -Nur linux-2.6.8.1/drivers/pci/Makefile linux-2.6.8.1-pci/drivers/pci/Makefile
--- linux-2.6.8.1/drivers/pci/Makefile 2004-08-14 19:56:15.000000000 +0900
+++ linux-2.6.8.1-pci/drivers/pci/Makefile 2004-09-13 10:44:53.000000000 +0900
@@ -5,6 +5,7 @@
obj-y += access.o bus.o probe.o remove.o pci.o quirks.o \
names.o pci-driver.o search.o pci-sysfs.o
obj-$(CONFIG_PROC_FS) += proc.o
+obj-$(CONFIG_PCI_ERROR_RECOVERY) += pci-rec.o
ifndef CONFIG_SPARC64
obj-y += setup-res.o
diff -Nur linux-2.6.8.1/drivers/pci/pci.c linux-2.6.8.1-pci/drivers/pci/pci.c
--- linux-2.6.8.1/drivers/pci/pci.c 2004-08-14 19:55:09.000000000 +0900
+++ linux-2.6.8.1-pci/drivers/pci/pci.c 2004-09-13 10:44:53.000000000 +0900
@@ -750,6 +750,9 @@
while ((dev = pci_find_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
pci_fixup_device(PCI_FIXUP_FINAL, dev);
}
+#ifdef CONFIG_PCI_ERROR_RECOVERY
+ pciwhole_lock_init();
+#endif
return 0;
}
diff -Nur linux-2.6.8.1/drivers/pci/pci-rec.c linux-2.6.8.1-pci/drivers/pci/pci-rec.c
--- linux-2.6.8.1/drivers/pci/pci-rec.c 1970-01-01 09:00:00.000000000 +0900
+++ linux-2.6.8.1-pci/drivers/pci/pci-rec.c 2004-09-13 11:11:22.000000000 +0900
@@ -0,0 +1,222 @@
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/spinlock.h>
+#include <asm/pci.h>
+#include <asm/page.h>
+#include <asm/dma.h> /* isa_dma_bridge_buggy */
+#include <asm/semaphore.h>
+#include <linux/list.h>
+#include <linux/rwsem.h>
+
+static rwlock_t pci_whole_lock;
+
+void
+pcibus_lock_init(struct pci_bus *bus)
+{
+ init_rwsem(&bus->bus_lock);
+}
+
+void
+pcibus_lock(struct pci_bus *bus)
+{
+ down_read(&bus->bus_lock);
+}
+
+void
+pcibus_unlock(struct pci_bus *bus)
+{
+ up_read(&bus->bus_lock);
+}
+
+void
+pciwhole_lock_init(void)
+{
+ rwlock_init(&pci_whole_lock);
+}
+
+void
+pciwhole_read_lock(void)
+{
+ read_lock(&pci_whole_lock);
+}
+
+void
+pciwhole_read_unlock(void)
+{
+ read_unlock(&pci_whole_lock);
+}
+
+void
+pciwhole_write_lock(void)
+{
+ write_lock(&pci_whole_lock);
+}
+
+void
+pciwhole_write_unlock(void)
+{
+ write_unlock(&pci_whole_lock);
+}
+
+#define IF_IS_PCI_ERROR(status) \
+ if ((status & PCI_STATUS_REC_TARGET_ABORT) \
+ ||(status & PCI_STATUS_REC_MASTER_ABORT) \
+ ||(status & PCI_STATUS_DETECTED_PARITY))
+
+void
+clear_pci_errors(struct pci_dev *dev)
+{
+ u16 status;
+ struct pci_dev *prootdev, *pdev;
+ struct pci_bus *pbus;
+
+ /* find root bus bridge */
+ if (!dev->bus->self) return;
+ for (pbus = dev->bus; pbus->parent && pbus->parent->self; pbus = pbus->parent) ;
+ prootdev = pbus->self;
+ /* check status (host bus bridge or PCI to PCI bridge) */
+ switch (prootdev->hdr_type) {
+ case PCI_HEADER_TYPE_NORMAL: /* 0 */
+ pci_read_config_word(prootdev, PCI_STATUS, &status);
+ break;
+ case PCI_HEADER_TYPE_BRIDGE: /* 1 */
+ pci_read_config_word(prootdev, PCI_SEC_STATUS, &status);
+ break;
+ case PCI_HEADER_TYPE_CARDBUS: /* 2 */
+ default:
+ BUG();
+ }
+ /* "status" holds error status or not. */
+ IF_IS_PCI_ERROR(status) {
+ pciwhole_write_lock();
+ if (!list_empty(&prootdev->working_device)) {
+ /* apply for all devices under same root bus bridges */
+ list_for_each_entry(pdev, &prootdev->working_device, working_device) {
+ pdev->err_status |= status;
+ }
+ }
+ /* status clear */
+ switch (prootdev->hdr_type) {
+ case PCI_HEADER_TYPE_NORMAL: /* 0 */
+ pci_write_config_word(prootdev, PCI_STATUS, status);
+ break;
+ case PCI_HEADER_TYPE_BRIDGE: /* 1 */
+ pci_write_config_word(prootdev, PCI_SEC_STATUS, status);
+ break;
+ case PCI_HEADER_TYPE_CARDBUS: /* 2 */
+ default:
+ BUG();
+ }
+ pciwhole_write_unlock();
+ }
+ /* initialize error holding variables */
+ dev->err_status = 0;
+ /* register to root bus bridge for Multiple I/O */
+ pcibus_lock(pbus);
+ list_add(&dev->working_device, &prootdev->working_device);
+ pcibus_unlock(pbus);
+}
+
+int
+read_pci_errors(struct pci_dev *dev)
+{
+ u32 status = 0;
+ u16 raw_br_status;
+ struct pci_dev *prootdev;
+ struct pci_bus *pbus;
+
+ /* find root bus bridge */
+ if (!dev->bus->self)
+ return 0; /* pseudo-no error */
+ for (pbus = dev->bus; pbus->parent && pbus->parent->self;
+ pbus = pbus->parent) ;
+ prootdev = pbus->self;
+ /* unregister from root bus bridge */
+ pcibus_lock(pbus);
+ if (list_empty(&prootdev->working_device)) {
+ BUG();
+ return 0;
+ }
+ list_del(&dev->working_device);
+ pcibus_unlock(pbus);
+ /* check status (host bus bridge or PCI to PCI bridge) */
+ switch (prootdev->hdr_type) {
+ case PCI_HEADER_TYPE_NORMAL: /* 0 */
+ pci_read_config_word(prootdev, PCI_STATUS, &raw_br_status);
+ break;
+ case PCI_HEADER_TYPE_BRIDGE: /* 1 */
+ pci_read_config_word(prootdev, PCI_SEC_STATUS, &raw_br_status);
+ break;
+ case PCI_HEADER_TYPE_CARDBUS: /* 2 */
+ default:
+ BUG();
+ }
+ status |= raw_br_status; /* current bridge status */
+ status |= dev->err_status; /* saved bridge status+ */
+ IF_IS_PCI_ERROR(status) { /* Target/Master Abort */
+ return 1;
+ }
+ return 0;
+}
+
+void pcidev_extra_init(struct pci_dev *dev)
+{
+ INIT_LIST_HEAD(&dev->working_device);
+ dev->err_status = 0;
+}
+
+u8
+readb_check(struct pci_dev *dev, u8 *addr)
+{
+ u8 val;
+
+ pciwhole_read_lock();
+ val = _readb_check(addr);
+ pciwhole_read_unlock();
+
+ return val;
+}
+
+u16
+readw_check(struct pci_dev *dev, u16 *addr)
+{
+ u16 val;
+
+ pciwhole_read_lock();
+ val = _readw_check(addr);
+ pciwhole_read_unlock();
+
+ return val;
+}
+
+u32
+readl_check(struct pci_dev *dev, u32 *addr)
+{
+ u32 val;
+
+ pciwhole_read_lock();
+ val = _readl_check(addr);
+ pciwhole_read_unlock();
+
+ return val;
+}
+
+EXPORT_SYMBOL (pcibus_lock_init);
+EXPORT_SYMBOL (pcibus_lock);
+EXPORT_SYMBOL (pcibus_unlock);
+EXPORT_SYMBOL (pciwhole_lock_init);
+EXPORT_SYMBOL (pciwhole_read_lock);
+EXPORT_SYMBOL (pciwhole_read_unlock);
+EXPORT_SYMBOL (pciwhole_write_lock);
+EXPORT_SYMBOL (pciwhole_write_unlock);
+EXPORT_SYMBOL (pcidev_extra_init);
+EXPORT_SYMBOL (clear_pci_errors);
+EXPORT_SYMBOL (read_pci_errors);
+EXPORT_SYMBOL (readb_check);
+EXPORT_SYMBOL (readw_check);
+EXPORT_SYMBOL (readl_check);
diff -Nur linux-2.6.8.1/drivers/pci/probe.c linux-2.6.8.1-pci/drivers/pci/probe.c
--- linux-2.6.8.1/drivers/pci/probe.c 2004-08-14 19:55:48.000000000 +0900
+++ linux-2.6.8.1-pci/drivers/pci/probe.c 2004-09-13 10:44:53.000000000 +0900
@@ -270,6 +270,9 @@
INIT_LIST_HEAD(&b->node);
INIT_LIST_HEAD(&b->children);
INIT_LIST_HEAD(&b->devices);
+#ifdef CONFIG_PCI_ERROR_RECOVERY
+ pcibus_lock_init(b);
+#endif
}
return b;
}
@@ -624,6 +627,9 @@
dev->dev.dma_mask = &dev->dma_mask;
dev->dev.coherent_dma_mask = 0xffffffffull;
+#ifdef CONFIG_PCI_ERROR_RECOVERY
+ pcidev_extra_init(dev);
+#endif
return dev;
}
diff -Nur linux-2.6.8.1/include/asm-i386/io.h linux-2.6.8.1-pci/include/asm-i386/io.h
--- linux-2.6.8.1/include/asm-i386/io.h 2004-08-14 19:56:23.000000000 +0900
+++ linux-2.6.8.1-pci/include/asm-i386/io.h 2004-09-13 10:44:53.000000000 +0900
@@ -364,4 +364,19 @@
BUILDIO(w,w,short)
BUILDIO(l,,int)
+static inline unsigned char _readb_check(unsigned char *addr)
+{
+ return readb(addr);
+}
+
+static inline unsigned short _readw_check(unsigned short *addr)
+{
+ return readw(addr);
+}
+
+static inline unsigned int _readl_check(unsigned int *addr)
+{
+ return readl(addr);
+}
+
#endif
diff -Nur linux-2.6.8.1/include/asm-i386/pci.h linux-2.6.8.1-pci/include/asm-i386/pci.h
--- linux-2.6.8.1/include/asm-i386/pci.h 2004-08-14 19:55:19.000000000 +0900
+++ linux-2.6.8.1-pci/include/asm-i386/pci.h 2004-09-13 11:06:00.000000000 +0900
@@ -99,6 +99,11 @@
{
}
+#ifdef CONFIG_PCI_ERROR_RECOVERY
+u8 readb_check(struct pci_dev *, u8*);
+u16 readw_check(struct pci_dev *, u16*);
+u32 readl_check(struct pci_dev *, u32*);
+#endif
#endif /* __KERNEL__ */
/* implement the pci_ DMA API in terms of the generic device dma_ one */
diff -Nur linux-2.6.8.1/include/asm-ia64/io.h linux-2.6.8.1-pci/include/asm-ia64/io.h
--- linux-2.6.8.1/include/asm-ia64/io.h 2004-08-14 19:54:48.000000000 +0900
+++ linux-2.6.8.1-pci/include/asm-ia64/io.h 2004-09-17 20:52:45.000000000 +0900
@@ -457,4 +457,39 @@
#define BIO_VMERGE_BOUNDARY (ia64_max_iommu_merge_mask + 1)
#endif
+static inline unsigned char
+_readb_check(unsigned char *addr)
+{
+ register unsigned long gr8 asm("r8");
+ unsigned char val;
+
+ val = readb(addr);
+ asm volatile ("add %0=%1,r0" : "=r"(gr8) : "r"(val));
+
+ return val;
+}
+
+static inline unsigned short
+_readw_check(unsigned short *addr)
+{
+ register unsigned long gr8 asm("r8");
+ unsigned short val;
+
+ val = readw(addr);
+ asm volatile ("add %0=%1,r0" : "=r"(gr8) : "r"(val));
+
+ return val;
+}
+
+static inline unsigned int
+_readl_check(unsigned int *addr)
+{
+ register unsigned long gr8 asm("r8");
+ unsigned int val;
+
+ val = readl(addr);
+ asm volatile ("add %0=%1,r0" : "=r"(gr8) : "r"(val));
+
+ return val;
+}
#endif /* _ASM_IA64_IO_H */
diff -Nur linux-2.6.8.1/include/asm-ia64/pci.h linux-2.6.8.1-pci/include/asm-ia64/pci.h
--- linux-2.6.8.1/include/asm-ia64/pci.h 2004-08-14 19:56:22.000000000 +0900
+++ linux-2.6.8.1-pci/include/asm-ia64/pci.h 2004-09-13 10:44:53.000000000 +0900
@@ -119,6 +119,11 @@
{
}
+#ifdef CONFIG_PCI_ERROR_RECOVERY
+u8 readb_check(struct pci_dev *, u8*);
+u16 readw_check(struct pci_dev *, u16*);
+u32 readl_check(struct pci_dev *, u32*);
+#endif
/* generic pci stuff */
#include <asm-generic/pci.h>
diff -Nur linux-2.6.8.1/include/linux/pci.h linux-2.6.8.1-pci/include/linux/pci.h
--- linux-2.6.8.1/include/linux/pci.h 2004-08-14 19:55:32.000000000 +0900
+++ linux-2.6.8.1-pci/include/linux/pci.h 2004-09-13 10:44:53.000000000 +0900
@@ -486,6 +486,10 @@
struct pci_dev {
struct list_head global_list; /* node in list of all PCI devices */
struct list_head bus_list; /* node in per-bus list */
+#ifdef CONFIG_PCI_ERROR_RECOVERY
+ struct list_head working_device;/* working device */
+ unsigned err_status; /* root bridge status and other error */
+#endif
struct pci_bus *bus; /* bus this device is on */
struct pci_bus *subordinate; /* bus this device bridges to */
@@ -568,6 +572,9 @@
struct pci_bus {
struct list_head node; /* node in list of buses */
+#ifdef CONFIG_PCI_ERROR_RECOVERY
+ struct rw_semaphore bus_lock; /* for serialized operation under same root bridge */
+#endif
struct pci_bus *parent; /* parent bus this bridge is on */
struct list_head children; /* list of child buses */
struct list_head devices; /* list of devices on this bus */
@@ -1021,5 +1028,21 @@
#define PCIPCI_VSFX 16
#define PCIPCI_ALIMAGIK 32
+#ifdef CONFIG_PCI_ERROR_RECOVERY
+void pcidev_extra_init(struct pci_dev *);
+void pcibus_lock_init(struct pci_bus *);
+void pcibus_lock(struct pci_bus *);
+void pcibus_unlock(struct pci_bus *);
+void pciwhole_lock_init(void);
+void pciwhole_read_lock(void);
+void pciwhole_read_unlock(void);
+void pciwhole_write_lock(void);
+void pciwhole_write_unlock(void);
+void clear_pci_errors(struct pci_dev *);
+int read_pci_errors(struct pci_dev *);
+u8 readb_check(struct pci_dev *, u8 *);
+u16 readw_check(struct pci_dev *, u16 *);
+u32 readl_check(struct pci_dev *, u32 *);
+#endif
#endif /* __KERNEL__ */
#endif /* LINUX_PCI_H */
On Fri, Sep 17, 2004 at 09:06:18PM +0900, Hidetoshi Seto wrote:
> This is the latest patch for PCI recovery.
> (merge Grant's text, fix spellmisses)
Hidetoshi,
sorry, I have more questions/comments...
And I still don't understand how some of the core pieces work.
Comments below just "nibble around the edges" (like a mouse
on a cracker).
> diff -Nur linux-2.6.8.1/include/asm-i386/io.h
> linux-2.6.8.1-pci/include/asm-i386/io.h
> --- linux-2.6.8.1/include/asm-i386/io.h 2004-08-14
...
> +static inline unsigned char _readb_check(unsigned char *addr)
> +{
> + return readb(addr);
> +}
Instead of adding those to io.h, wouldn't it be better to add
a new header file? e.g io_check.h or something like that.
io.h is cluttered up with too much stuff already.
Anyone who wants to use these functions will be writing new
code and a new header file shouldn't be a problem.
Oh...and linus' recent addition of iomap.h to 2.6.9-rcX kernels:
http://www.ussg.iu.edu/hypermail/linux/kernel/0409.1/2561.html
This might be an opportunity for you to make the new interface
a bit more aware of error recovery.
It would make sense to integrate directly into his new design
for new kernel functionality. If someone is (re)writing code
to use the new interfaces, they might do it differently
if the pci error recovery is part of that.
Sorry, I don't mean to upset the your plans and suspect
what you are doing will be useful for existing 2.6 kernels
shipped by distro's.
> diff -Nur linux-2.6.8.1/include/asm-ia64/io.h
> linux-2.6.8.1-pci/include/asm-ia64/io.h
...
> +static inline unsigned char
> +_readb_check(unsigned char *addr)
> +{
> + register unsigned long gr8 asm("r8");
> + unsigned char val;
> +
> + val = readb(addr);
> + asm volatile ("add %0=%1,r0" : "=r"(gr8) : "r"(val));
Sorry - I don't understand the intent of the asm here.
Would a short comment be sufficient to explain?
I'm trying to understand why it's different from i386 and
not what "add" does.
...
> +u8 readb_check(struct pci_dev *, u8 *);
> +u16 readw_check(struct pci_dev *, u16 *);
> +u32 readl_check(struct pci_dev *, u32 *);
These function protoypes are added to i386 and ia64 asm/pci.h and
to linux/pci.h.
Do you really need to add the same function proto to asm/pci.h?
Or am I overlooking something? (It's been a long day again...)
thanks,
grant
Grant,
thank you for your constant comment/interest.
Grant Grundler wrote:
>>diff -Nur linux-2.6.8.1/include/asm-i386/io.h
>>linux-2.6.8.1-pci/include/asm-i386/io.h
>>--- linux-2.6.8.1/include/asm-i386/io.h 2004-08-14
>
> ...
>
>>+static inline unsigned char _readb_check(unsigned char *addr)
>>+{
>>+ return readb(addr);
>>+}
>
>
> Instead of adding those to io.h, wouldn't it be better to add
> a new header file? e.g io_check.h or something like that.
>
> io.h is cluttered up with too much stuff already.
> Anyone who wants to use these functions will be writing new
> code and a new header file shouldn't be a problem.
Sounds good.
Hmm, I tend to avoid creating new file in the Linux tree... :-p
> Oh...and linus' recent addition of iomap.h to 2.6.9-rcX kernels:
> http://www.ussg.iu.edu/hypermail/linux/kernel/0409.1/2561.html
>
> This might be an opportunity for you to make the new interface
> a bit more aware of error recovery.
>
> It would make sense to integrate directly into his new design
> for new kernel functionality. If someone is (re)writing code
> to use the new interfaces, they might do it differently
> if the pci error recovery is part of that.
>
> Sorry, I don't mean to upset the your plans and suspect
> what you are doing will be useful for existing 2.6 kernels
> shipped by distro's.
Thank you for your information.
I hadn't notice the Linus's post... iomap.h is very interesting.
In fact, I'm targeting current distro's. However now I think it is
worth to reconsider my plan if we are entering a great transitional
stage in the development of the kernel infrastructure...
>>diff -Nur linux-2.6.8.1/include/asm-ia64/io.h
>>linux-2.6.8.1-pci/include/asm-ia64/io.h
>
> ...
>
>>+static inline unsigned char
>>+_readb_check(unsigned char *addr)
>>+{
>>+ register unsigned long gr8 asm("r8");
>>+ unsigned char val;
>>+
>>+ val = readb(addr);
>>+ asm volatile ("add %0=%1,r0" : "=r"(gr8) : "r"(val));
>
>
> Sorry - I don't understand the intent of the asm here.
> Would a short comment be sufficient to explain?
>
> I'm trying to understand why it's different from i386 and
> not what "add" does.
This part is ia64 specific staff... we need something like "add" to
make sure the value is not poisoned. Since the processor asserts an
MCA at the time when the poisoned value is "consumed" - more properly,
the MCA is signaled at or before the use of the IO read transaction:
LabelA: ld8 r15 = [r16] // Load
LabelB: Mov r17 = r18;;
:
LabelX: Mov r22 = r15 // MCA signaled at or before this instruction
So the "add" make us sure that read_pci_errors() which should follow
this readX_check() never fail to catch all MCA that could be caused by
values fetched by some readX_check().
AFAIK, this "add" works as something like barrier(), definitely certain,
and quick than PAL_MC_DRAIN call.
>>+u8 readb_check(struct pci_dev *, u8 *);
>>+u16 readw_check(struct pci_dev *, u16 *);
>>+u32 readl_check(struct pci_dev *, u32 *);
>
>
> These function protoypes are added to i386 and ia64 asm/pci.h and
> to linux/pci.h.
> Do you really need to add the same function proto to asm/pci.h?
> Or am I overlooking something? (It's been a long day again...)
No no, it's my overlooking... They are duplicated.
Add it only linux/pci.h.
Thanks,
H.Seto