Re: [03/12,v3] pci: fsl: add PCI indirect access support
From: Scott Wood <hidden>
Date: 2014-01-03 22:33:20
Also in:
linux-pci
On Wed, Oct 23, 2013 at 06:41:25PM +0800, Minghuan Lian wrote:
quoted hunk ↗ jump to hunk
The patch adds PCI indirect read/write functions. The main code is ported from arch/powerpc/sysdev/indirect_pci.c. We use general IO API iowrite32be/ioread32be instead of out_be32/in_be32, and use structure fsl_Pci instead of PowerPC's pci_controller. The patch also provides fsl_pcie_check_link() to check PCI link. The weak function fsl_arch_pci_exclude_device() is provided to call ppc_md.pci_exclude_device() for PowerPC architecture. Signed-off-by: Minghuan Lian <redacted> --- change log: v1-v3: Derived from http://patchwork.ozlabs.org/patch/278965/ Based on upstream master. Based on the discussion of RFC version here http://patchwork.ozlabs.org/patch/274487/ drivers/pci/host/pci-fsl-common.c | 169 ++++++++++++++++++++++++++++++++------ include/linux/fsl/pci-common.h | 6 ++ 2 files changed, 151 insertions(+), 24 deletions(-)diff --git a/drivers/pci/host/pci-fsl-common.c b/drivers/pci/host/pci-fsl-common.c index 69d338b..8bc9a64 100644 --- a/drivers/pci/host/pci-fsl-common.c +++ b/drivers/pci/host/pci-fsl-common.c@@ -35,52 +35,173 @@ #include <sysdev/fsl_soc.h> #include <sysdev/fsl_pci.h> -static int fsl_pcie_check_link(struct pci_controller *hose) +/* Indirect type */ +#define INDIRECT_TYPE_EXT_REG 0x00000002 +#define INDIRECT_TYPE_SURPRESS_PRIMARY_BUS 0x00000004 +#define INDIRECT_TYPE_NO_PCIE_LINK 0x00000008 +#define INDIRECT_TYPE_BIG_ENDIAN 0x00000010 +#define INDIRECT_TYPE_FSL_CFG_REG_LINK 0x00000040
Why are these here rather than in the header, given that you have indirect_type in the struct in the header?
+int __weak fsl_arch_pci_exclude_device(struct fsl_pci *pci, u8 bus, u8 devfn)
+{
+ return PCIBIOS_SUCCESSFUL;
+}
+
+static int fsl_pci_read_config(struct fsl_pci *pci, int bus, int devfn,
+ int offset, int len, u32 *val)
+{
+ u32 bus_no, reg, data;
+
+ if (pci->indirect_type & INDIRECT_TYPE_NO_PCIE_LINK) {
+ if (bus != pci->first_busno)
+ return PCIBIOS_DEVICE_NOT_FOUND;
+ if (devfn != 0)
+ return PCIBIOS_DEVICE_NOT_FOUND;
+ }A lot of this seems duplicated from arch/powerpc/sysdev/indirect_pci.c. How generally applicable is that file to non-PPC implementations? At a minimum I see a similar file in arch/microblaze. It should probably eventually be moved to common code, rather than duplicated again. A prerequisite for that would be making common the dependencies it has on the rest of what is currently arch PCI infrastructure; until then, it's probably better to just have the common fsl-pci code know how to interface with the appropriate PPC/ARM code rather than trying to copy the infrastructure as well. -Scott