From: Ley Foon Tan <lftan@xxxxxxxxxx>
Check TLP packet successful completion status. This fix the issue when
accessing multi-function devices in enumeration process, TLP will return
error when accessing non-exist function number. Returns PCI error code
instead of generic errno.
Tested on Ethernet adapter card with multi-functions.
[bhelgaas: simplify completion status checking code]
Signed-off-by: Ley Foon Tan <lftan@xxxxxxxxxx>
Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
---
drivers/pci/host/pcie-altera.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/drivers/pci/host/pcie-altera.c b/drivers/pci/host/pcie-altera.c
index ed736a9..072255d 100644
--- a/drivers/pci/host/pcie-altera.c
+++ b/drivers/pci/host/pcie-altera.c
@@ -55,6 +55,7 @@
#define TLP_CFG_DW2(bus, devfn, offset) \
(((bus) << 24) | ((devfn) << 16) | (offset))
#define TLP_REQ_ID(bus, devfn) (((bus) << 8) | (devfn))
+#define TLP_COMP_STATUS(s) (((s) >> 12) & 7)
#define TLP_HDR_SIZE 3
#define TLP_LOOP 500
#define RP_DEVFN 0
@@ -171,6 +172,7 @@ static int tlp_read_packet(struct altera_pcie *pcie, u32 *value)
bool sop = 0;
u32 ctrl;
u32 reg0, reg1;
+ u32 comp_status = 1;
/*
* Minimum 2 loops to read TLP headers and 1 loop to read data
@@ -182,19 +184,25 @@ static int tlp_read_packet(struct altera_pcie *pcie, u32 *value)
reg0 = cra_readl(pcie, RP_RXCPL_REG0);
reg1 = cra_readl(pcie, RP_RXCPL_REG1);
- if (ctrl & RP_RXCPL_SOP)
+ if (ctrl & RP_RXCPL_SOP) {
sop = true;
+ comp_status = TLP_COMP_STATUS(reg1);
+ }
if (ctrl & RP_RXCPL_EOP) {
+ if (comp_status)
+ return PCIBIOS_DEVICE_NOT_FOUND;
+
if (value)
*value = reg0;
+
return PCIBIOS_SUCCESSFUL;
}
}
udelay(5);
}
- return -ENOENT;
+ return PCIBIOS_DEVICE_NOT_FOUND;
}
static void tlp_write_packet(struct altera_pcie *pcie, u32 *headers,
--
2.9.3
