On 01/12/2013 11:46 AM, Nathan Hintz wrote:
> For PCI config space access offsets < 256 for device '0',
> bcma_extpci_write_config performs an 'ioremap_nocache' on a 4 byte
> section of the PCI config space (an area that has already
> previously been mapped), and then subsequently unmaps that 4 byte
> section. This can't be a good thing for future read access from
> that now unmapped location. Modify the config space writes to use
> the existing access functions (similar to how it is done for the reads).
>
> Signed-off-by: Nathan Hintz <nlhintz@xxxxxxxxxxx>
> ---
> drivers/bcma/driver_pci_host.c | 22 +++++++++++-----------
> 1 files changed, 11 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/bcma/driver_pci_host.c b/drivers/bcma/driver_pci_host.c
> index 187cc9f..e1381ba 100644
> --- a/drivers/bcma/driver_pci_host.c
> +++ b/drivers/bcma/driver_pci_host.c
> @@ -149,7 +149,7 @@ static int bcma_extpci_write_config(struct bcma_drv_pci *pc, unsigned int dev,
> const void *buf, int len)
> {
> int err = -EINVAL;
> - u32 addr = 0, val = 0;
> + u32 addr, val;
> void __iomem *mmio = 0;
> u16 chipid = pc->core->bus->chipinfo.id;
>
> @@ -165,12 +165,10 @@ static int bcma_extpci_write_config(struct bcma_drv_pci *pc, unsigned int dev,
> * requires indirect access.
> */
> if (off < PCI_CONFIG_SPACE_SIZE) {
> - addr = pc->core->addr + BCMA_CORE_PCI_PCICFG0;
> + addr = BCMA_CORE_PCI_PCICFG0;
> addr |= (func << 8);
> addr |= (off & 0xfc);
> - mmio = ioremap_nocache(addr, sizeof(val));
> - if (!mmio)
> - goto out;
> + val = pcicore_read32(pc, addr);
> }
off >= PCI_CONFIG_SPACE_SIZE is not handled here, but I think it should
be. This part of the function should use the same code as used in
bcma_extpci_read_config().
Your patch improves this, but I think there is an other flaw in the code.
> } else {
> addr = bcma_get_cfgspace_addr(pc, dev, func, off);
> @@ -189,12 +187,10 @@ static int bcma_extpci_write_config(struct bcma_drv_pci *pc, unsigned int dev,
>
> switch (len) {
> case 1:
> - val = readl(mmio);
> val &= ~(0xFF << (8 * (off & 3)));
> val |= *((const u8 *)buf) << (8 * (off & 3));
> break;
> case 2:
> - val = readl(mmio);
> val &= ~(0xFFFF << (8 * (off & 3)));
> val |= *((const u16 *)buf) << (8 * (off & 3));
> break;
> @@ -202,13 +198,17 @@ static int bcma_extpci_write_config(struct bcma_drv_pci *pc, unsigned int dev,
> val = *((const u32 *)buf);
> break;
> }
> - if (dev == 0 && !addr) {
> + if (dev == 0) {
> /* accesses to config registers with offsets >= 256
> * requires indirect access.
> */
> - addr = (func << 12);
> - addr |= (off & 0x0FFF);
> - bcma_pcie_write_config(pc, addr, val);
> + if (off >= PCI_CONFIG_SPACE_SIZE) {
> + addr = (func << 12);
> + addr |= (off & 0x0FFF);
> + bcma_pcie_write_config(pc, addr, val);
> + } else {
> + pcicore_write32(pc, addr, val);
> + }
> } else {
> writel(val, mmio);
>
>
--
To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
