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-rw-r--r--drivers/pci/pci.c21
-rw-r--r--drivers/pci/quirks.c28
2 files changed, 41 insertions, 8 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 4e4c295a049f..1f9a7a03847b 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -47,6 +47,19 @@ unsigned long pci_cardbus_mem_size = DEFAULT_CARDBUS_MEM_SIZE;
unsigned long pci_hotplug_io_size = DEFAULT_HOTPLUG_IO_SIZE;
unsigned long pci_hotplug_mem_size = DEFAULT_HOTPLUG_MEM_SIZE;
+#ifndef PCI_CACHE_LINE_BYTES
+#define PCI_CACHE_LINE_BYTES L1_CACHE_BYTES
+#endif
+
+/*
+ * The default CLS is used if arch didn't set CLS explicitly and not
+ * all pci devices agree on the same value. Arch can override either
+ * the dfl or actual value as it sees fit. Don't forget this is
+ * measured in 32-bit words, not bytes.
+ */
+u8 pci_dfl_cache_line_size __initdata = PCI_CACHE_LINE_BYTES >> 2;
+u8 pci_cache_line_size;
+
/**
* pci_bus_max_busnr - returns maximum PCI bus number of given bus' children
* @bus: pointer to PCI bus structure to search
@@ -1883,14 +1896,6 @@ void pci_clear_mwi(struct pci_dev *dev)
#else
-#ifndef PCI_CACHE_LINE_BYTES
-#define PCI_CACHE_LINE_BYTES L1_CACHE_BYTES
-#endif
-
-/* This can be overridden by arch code. */
-/* Don't forget this is measured in 32-bit words, not bytes */
-u8 pci_cache_line_size = PCI_CACHE_LINE_BYTES / 4;
-
/**
* pci_set_cacheline_size - ensure the CACHE_LINE_SIZE register is programmed
* @dev: the PCI device for which MWI is to be enabled
diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 245d2cdb4765..1812ae7698de 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -2595,9 +2595,37 @@ void pci_fixup_device(enum pci_fixup_pass pass, struct pci_dev *dev)
static int __init pci_apply_final_quirks(void)
{
struct pci_dev *dev = NULL;
+ u8 cls = 0;
+ u8 tmp;
+
+ if (pci_cache_line_size)
+ printk(KERN_DEBUG "PCI: CLS %u bytes\n",
+ pci_cache_line_size << 2);
while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
pci_fixup_device(pci_fixup_final, dev);
+ /*
+ * If arch hasn't set it explicitly yet, use the CLS
+ * value shared by all PCI devices. If there's a
+ * mismatch, fall back to the default value.
+ */
+ if (!pci_cache_line_size) {
+ pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &tmp);
+ if (!cls)
+ cls = tmp;
+ if (!tmp || cls == tmp)
+ continue;
+
+ printk(KERN_DEBUG "PCI: CLS mismatch (%u != %u), "
+ "using %u bytes\n", cls << 2, tmp << 2,
+ pci_dfl_cache_line_size << 2);
+ pci_cache_line_size = pci_dfl_cache_line_size;
+ }
+ }
+ if (!pci_cache_line_size) {
+ printk(KERN_DEBUG "PCI: CLS %u bytes, default %u\n",
+ cls << 2, pci_dfl_cache_line_size << 2);
+ pci_cache_line_size = cls;
}
return 0;