From db674ed450f113518285f410c93abecd93e71a2f Mon Sep 17 00:00:00 2001 From: Sylvain Munaut Date: Fri, 6 Jan 2006 00:11:36 -0800 Subject: [PATCH] [PATCH] ppc32: Fix MPC52xx configuration space access This patch takes care of an errata of the MPC5200 by avoiding 32 bits access in type 1 configuration accesses. All others accesses are still 32 bits wide. It also adds some mb() since the simple out_be(...) are not sufficient in this case. Signed-off-by: Sylvain Munaut Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/ppc/syslib/mpc52xx_pci.c | 83 +++++++++++++++++++++++++++++++++++-------- 1 file changed, 69 insertions(+), 14 deletions(-) diff --git a/arch/ppc/syslib/mpc52xx_pci.c b/arch/ppc/syslib/mpc52xx_pci.c index e6cb3e2..2c5e6dd 100644 --- a/arch/ppc/syslib/mpc52xx_pci.c +++ b/arch/ppc/syslib/mpc52xx_pci.c @@ -24,6 +24,12 @@ #include +/* This macro is defined to activate the workaround for the bug + 435 of the MPC5200 (L25R). With it activated, we don't do any + 32 bits configuration access during type-1 cycles */ +#define MPC5200_BUG_435_WORKAROUND + + static int mpc52xx_pci_read_config(struct pci_bus *bus, unsigned int devfn, int offset, int len, u32 *val) @@ -40,17 +46,39 @@ mpc52xx_pci_read_config(struct pci_bus *bus, unsigned int devfn, ((bus->number - hose->bus_offset) << 16) | (devfn << 8) | (offset & 0xfc)); + mb(); + +#ifdef MPC5200_BUG_435_WORKAROUND + if (bus->number != hose->bus_offset) { + switch (len) { + case 1: + value = in_8(((u8 __iomem *)hose->cfg_data) + (offset & 3)); + break; + case 2: + value = in_le16(((u16 __iomem *)hose->cfg_data) + ((offset>>1) & 1)); + break; + + default: + value = in_le16((u16 __iomem *)hose->cfg_data) | + (in_le16(((u16 __iomem *)hose->cfg_data) + 1) << 16); + break; + } + } + else +#endif + { + value = in_le32(hose->cfg_data); - value = in_le32(hose->cfg_data); - - if (len != 4) { - value >>= ((offset & 0x3) << 3); - value &= 0xffffffff >> (32 - (len << 3)); + if (len != 4) { + value >>= ((offset & 0x3) << 3); + value &= 0xffffffff >> (32 - (len << 3)); + } } *val = value; out_be32(hose->cfg_addr, 0); + mb(); return PCIBIOS_SUCCESSFUL; } @@ -71,21 +99,48 @@ mpc52xx_pci_write_config(struct pci_bus *bus, unsigned int devfn, ((bus->number - hose->bus_offset) << 16) | (devfn << 8) | (offset & 0xfc)); + mb(); + +#ifdef MPC5200_BUG_435_WORKAROUND + if (bus->number != hose->bus_offset) { + switch (len) { + case 1: + out_8(((u8 __iomem *)hose->cfg_data) + + (offset & 3), val); + break; + case 2: + out_le16(((u16 __iomem *)hose->cfg_data) + + ((offset>>1) & 1), val); + break; + + default: + out_le16((u16 __iomem *)hose->cfg_data, + (u16)val); + out_le16(((u16 __iomem *)hose->cfg_data) + 1, + (u16)(val>>16)); + break; + } + } + else +#endif + { + if (len != 4) { + value = in_le32(hose->cfg_data); - if (len != 4) { - value = in_le32(hose->cfg_data); + offset = (offset & 0x3) << 3; + mask = (0xffffffff >> (32 - (len << 3))); + mask <<= offset; - offset = (offset & 0x3) << 3; - mask = (0xffffffff >> (32 - (len << 3))); - mask <<= offset; + value &= ~mask; + val = value | ((val << offset) & mask); + } - value &= ~mask; - val = value | ((val << offset) & mask); + out_le32(hose->cfg_data, val); } - - out_le32(hose->cfg_data, val); + mb(); out_be32(hose->cfg_addr, 0); + mb(); return PCIBIOS_SUCCESSFUL; } -- 2.7.4