Re: [PATCH] MPC5200 - Make PCI work in 2.6 with the IceCube 5200
From: Sylvain Munaut <hidden>
Date: 2005-10-11 23:18:23
Hi Wolfgang, Weird, I would have thought the usage of in_be out_be macro ensured that. But after checking, they only include a isync instruction which doesn't guarantee memory access will be done while mb() uses sync that does guarantee that. Any one can comment on that ? Wasn't the purpose of the in_be out_be to ensure that ? Sylvain Wolfgang Denk wrote:
Hello, the following patch is against the current 2.6 kernel.org tree (commit f96c3bbe91117402f13119ce9e609db9087ed58f): As a prerequisite for a working system, the following two poatches are needed, too: http://patchwork.ozlabs.org/linuxppc/patch?id=2018 http://patchwork.ozlabs.org/linuxppc/patch?id=2017
quoted hunk ↗ jump to hunk
!-------------------------------------------------------------flip- [patch] making PCI work in the MPC5200 Patch by Alessandro Rubini, 08 Oct 2005 Make PCI work in 2.6 with the IceCube 5200. Without the memory barriers all PCI config reads returned 0xffffffff (actually, there may be more mb() than needed). Using wmb(); was not enough to be able to read configuration registers. Signed-off by Alessandro Rubini [off-list ref] Signed-off by Wolfgang Denk [off-list ref] --- commit cdd7fdf10b3cbb7eb82cacc7ba5dba3553020f49 tree 97d045b44c87c00a4b3fe5bca57b479be87e68b6 parent 509b5c9fcbfe7fcae7d4f98946e4dc9794d68645 author Wolfgang Denk [off-list ref] Sat, 08 Oct 2005 22:41:53 +0200 committer Wolfgang Denk [off-list ref] Sat, 08 Oct 2005 22:41:53 +0200 arch/ppc/syslib/mpc52xx_pci.c | 4 ++++ 1 files changed, 4 insertions(+), 0 deletions(-)diff --git a/arch/ppc/syslib/mpc52xx_pci.c b/arch/ppc/syslib/mpc52xx_pci.c --- a/arch/ppc/syslib/mpc52xx_pci.c +++ b/arch/ppc/syslib/mpc52xx_pci.c@@ -39,6 +39,7 @@ mpc52xx_pci_read_config(struct pci_bus * ((bus->number - hose->bus_offset) << 16) | (devfn << 8) | (offset & 0xfc)); + mb(); value = in_le32(hose->cfg_data);@@ -70,6 +71,7 @@ mpc52xx_pci_write_config(struct pci_bus ((bus->number - hose->bus_offset) << 16) | (devfn << 8) | (offset & 0xfc)); + mb(); if (len != 4) { value = in_le32(hose->cfg_data);@@ -80,9 +82,11 @@ mpc52xx_pci_write_config(struct pci_bus value &= ~mask; val = value | ((val << offset) & mask); + mb(); } out_le32(hose->cfg_data, val); + mb(); out_be32(hose->cfg_addr, 0);
!-------------------------------------------------------------flip- Best regards, Wolfgang Denk