[PATCH] PCI: fix up word-aligned 16-bit PCI config access through sysfs
This patch adds the possibility to do word-aligned 16-bit atomic PCI
configuration space accesses via the sysfs PCI interface. As a result, problems
with Emulex LFPC on IBM PowerPC64 are fixed.
Patch is present in SLES 9 SP1.
Signed-off-by: Vojtech Pavlik <vojtech@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index d57ae71..8568b20 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -91,6 +91,7 @@
struct pci_dev *dev = to_pci_dev(container_of(kobj,struct device,kobj));
unsigned int size = 64;
loff_t init_off = off;
+ u8 *data = (u8*) buf;
/* Several chips lock up trying to read undefined config space */
if (capable(CAP_SYS_ADMIN)) {
@@ -108,30 +109,47 @@
size = count;
}
- while (off & 3) {
- unsigned char val;
+ if ((off & 1) && size) {
+ u8 val;
pci_read_config_byte(dev, off, &val);
- buf[off - init_off] = val;
+ data[off - init_off] = val;
off++;
- if (--size == 0)
- break;
+ size--;
+ }
+
+ if ((off & 3) && size > 2) {
+ u16 val;
+ pci_read_config_word(dev, off, &val);
+ data[off - init_off] = val & 0xff;
+ data[off - init_off + 1] = (val >> 8) & 0xff;
+ off += 2;
+ size -= 2;
}
while (size > 3) {
- unsigned int val;
+ u32 val;
pci_read_config_dword(dev, off, &val);
- buf[off - init_off] = val & 0xff;
- buf[off - init_off + 1] = (val >> 8) & 0xff;
- buf[off - init_off + 2] = (val >> 16) & 0xff;
- buf[off - init_off + 3] = (val >> 24) & 0xff;
+ data[off - init_off] = val & 0xff;
+ data[off - init_off + 1] = (val >> 8) & 0xff;
+ data[off - init_off + 2] = (val >> 16) & 0xff;
+ data[off - init_off + 3] = (val >> 24) & 0xff;
off += 4;
size -= 4;
}
- while (size > 0) {
- unsigned char val;
+ if (size >= 2) {
+ u16 val;
+ pci_read_config_word(dev, off, &val);
+ data[off - init_off] = val & 0xff;
+ data[off - init_off + 1] = (val >> 8) & 0xff;
+ off += 2;
+ size -= 2;
+ }
+
+ if (size > 0) {
+ u8 val;
pci_read_config_byte(dev, off, &val);
- buf[off - init_off] = val;
+ data[off - init_off] = val;
off++;
--size;
}
@@ -145,6 +163,7 @@
struct pci_dev *dev = to_pci_dev(container_of(kobj,struct device,kobj));
unsigned int size = count;
loff_t init_off = off;
+ u8 *data = (u8*) buf;
if (off > dev->cfg_size)
return 0;
@@ -152,26 +171,41 @@
size = dev->cfg_size - off;
count = size;
}
-
- while (off & 3) {
- pci_write_config_byte(dev, off, buf[off - init_off]);
+
+ if ((off & 1) && size) {
+ pci_write_config_byte(dev, off, data[off - init_off]);
off++;
- if (--size == 0)
- break;
+ size--;
}
+
+ if ((off & 3) && size > 2) {
+ u16 val = data[off - init_off];
+ val |= (u16) data[off - init_off + 1] << 8;
+ pci_write_config_word(dev, off, val);
+ off += 2;
+ size -= 2;
+ }
while (size > 3) {
- unsigned int val = buf[off - init_off];
- val |= (unsigned int) buf[off - init_off + 1] << 8;
- val |= (unsigned int) buf[off - init_off + 2] << 16;
- val |= (unsigned int) buf[off - init_off + 3] << 24;
+ u32 val = data[off - init_off];
+ val |= (u32) data[off - init_off + 1] << 8;
+ val |= (u32) data[off - init_off + 2] << 16;
+ val |= (u32) data[off - init_off + 3] << 24;
pci_write_config_dword(dev, off, val);
off += 4;
size -= 4;
}
+
+ if (size >= 2) {
+ u16 val = data[off - init_off];
+ val |= (u16) data[off - init_off + 1] << 8;
+ pci_write_config_word(dev, off, val);
+ off += 2;
+ size -= 2;
+ }
- while (size > 0) {
- pci_write_config_byte(dev, off, buf[off - init_off]);
+ if (size) {
+ pci_write_config_byte(dev, off, data[off - init_off]);
off++;
--size;
}