From bdc2bda7c4dd253026cc1fce45fc939304749029 Mon Sep 17 00:00:00 2001 From: Dean Nelson Date: Tue, 9 Mar 2010 22:26:48 -0500 Subject: [PATCH] PCI: fix access of PCI_X_CMD by pcix get and set mmrbc functions An e1000 driver on a system with a PCI-X bus was always being returned a value of 135 from both pcix_get_mmrbc() and pcix_set_mmrbc(). This value reflects an error return of PCIBIOS_BAD_REGISTER_NUMBER from pci_bus_read_config_dword(,, cap + PCI_X_CMD,). This is because for a dword, the following portion of the PCI_OP_READ() macro: if (PCI_##size##_BAD) return PCIBIOS_BAD_REGISTER_NUMBER; expands to: if (pos & 3) return PCIBIOS_BAD_REGISTER_NUMBER; And is always true for 'cap + PCI_X_CMD', which is 0xe4 + 2 = 0xe6. ('cap' is the result of calling pci_find_capability(, PCI_CAP_ID_PCIX).) The same problem exists for pci_bus_write_config_dword(,, cap + PCI_X_CMD,). In both cases, instead of calling _dword(), _word() should be called. Cc: stable@kernel.org Signed-off-by: Dean Nelson Signed-off-by: Jesse Barnes --- drivers/pci/pci.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 9af986085d09..5c80b59c5931 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -2601,13 +2601,13 @@ EXPORT_SYMBOL(pcix_get_max_mmrbc); int pcix_get_mmrbc(struct pci_dev *dev) { int ret, cap; - u32 cmd; + u16 cmd; cap = pci_find_capability(dev, PCI_CAP_ID_PCIX); if (!cap) return -EINVAL; - ret = pci_read_config_dword(dev, cap + PCI_X_CMD, &cmd); + ret = pci_read_config_word(dev, cap + PCI_X_CMD, &cmd); if (!ret) ret = 512 << ((cmd & PCI_X_CMD_MAX_READ) >> 2); @@ -2627,7 +2627,8 @@ EXPORT_SYMBOL(pcix_get_mmrbc); int pcix_set_mmrbc(struct pci_dev *dev, int mmrbc) { int cap, err = -EINVAL; - u32 stat, cmd, v, o; + u32 stat, v, o; + u16 cmd; if (mmrbc < 512 || mmrbc > 4096 || !is_power_of_2(mmrbc)) goto out; @@ -2645,7 +2646,7 @@ int pcix_set_mmrbc(struct pci_dev *dev, int mmrbc) if (v > (stat & PCI_X_STATUS_MAX_READ) >> 21) return -E2BIG; - err = pci_read_config_dword(dev, cap + PCI_X_CMD, &cmd); + err = pci_read_config_word(dev, cap + PCI_X_CMD, &cmd); if (err) goto out; @@ -2657,7 +2658,7 @@ int pcix_set_mmrbc(struct pci_dev *dev, int mmrbc) cmd &= ~PCI_X_CMD_MAX_READ; cmd |= v << 2; - err = pci_write_config_dword(dev, cap + PCI_X_CMD, cmd); + err = pci_write_config_word(dev, cap + PCI_X_CMD, cmd); } out: return err; -- GitLab