sh: Fix up early PCI PERR/SERR IRQ handling.

This adds support for handling early PERR/SERR triggering in between
controller registration and the initial bus scan. Buggy cards end up
asserting these as soon as the M66EN scan is undertaken, resulting in
an early crash.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 42 insertions, 9 deletions

diff --git a/arch/sh/drivers/pci/pci.c b/arch/sh/drivers/pci/pci.c
index f4a69833fce..41d8f014f1d 100644
--- a/arch/sh/drivers/pci/pci.c
+++ b/arch/sh/drivers/pci/pci.c
@@ -204,7 +204,7 @@ void pcibios_align_resource(void *data, struct resource *res,
 }
 
 void pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
-			 struct resource *res)
+			     struct resource *res)
 {
 	struct pci_channel *hose = dev->sysdata;
 	unsigned long offset = 0;
@@ -218,9 +218,8 @@ void pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
 	region->end = res->end - offset;
 }
 
-void __devinit
-pcibios_bus_to_resource(struct pci_dev *dev, struct resource *res,
-			struct pci_bus_region *region)
+void pcibios_bus_to_resource(struct pci_dev *dev, struct resource *res,
+			     struct pci_bus_region *region)
 {
 	struct pci_channel *hose = dev->sysdata;
 	unsigned long offset = 0;
@@ -303,12 +302,41 @@ char * __devinit pcibios_setup(char *str)
 	return str;
 }
 
+static void __init
+pcibios_bus_report_status_early(struct pci_channel *hose,
+				int top_bus, int current_bus,
+				unsigned int status_mask, int warn)
+{
+	unsigned int pci_devfn;
+	u16 status;
+	int ret;
+
+	for (pci_devfn = 0; pci_devfn < 0xff; pci_devfn++) {
+		if (PCI_FUNC(pci_devfn))
+			continue;
+		ret = early_read_config_word(hose, top_bus, current_bus,
+					     pci_devfn, PCI_STATUS, &status);
+		if (ret != PCIBIOS_SUCCESSFUL)
+			continue;
+		if (status == 0xffff)
+			continue;
+
+		early_write_config_word(hose, top_bus, current_bus,
+					pci_devfn, PCI_STATUS,
+					status & status_mask);
+		if (warn)
+			printk("(%02x:%02x: %04X) ", current_bus,
+			       pci_devfn, status);
+	}
+}
+
 /*
  * We can't use pci_find_device() here since we are
  * called from interrupt context.
  */
-static void pcibios_bus_report_status(struct pci_bus *bus,
-		unsigned int status_mask, int warn)
+static void __init_refok
+pcibios_bus_report_status(struct pci_bus *bus, unsigned int status_mask,
+			  int warn)
 {
 	struct pci_dev *dev;
 
@@ -341,12 +369,17 @@ static void pcibios_bus_report_status(struct pci_bus *bus,
 			pcibios_bus_report_status(dev->subordinate, status_mask, warn);
 }
 
-void pcibios_report_status(unsigned int status_mask, int warn)
+void __init_refok pcibios_report_status(unsigned int status_mask, int warn)
 {
 	struct pci_channel *hose;
 
-	for (hose = hose_head; hose; hose = hose->next)
-		pcibios_bus_report_status(hose->bus, status_mask, warn);
+	for (hose = hose_head; hose; hose = hose->next) {
+		if (unlikely(!hose->bus))
+			pcibios_bus_report_status_early(hose, hose_head->index,
+					hose->index, status_mask, warn);
+		else
+			pcibios_bus_report_status(hose->bus, status_mask, warn);
+	}
 }
 
 int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,