[PATCH] Exchange the Assignments of `MEMORYs' and `CFGs/IOs' in Designware PCIe Driver

From: dongbo (E)
Date: Tue Jun 28 2016 - 04:16:11 EST


From: Dong Bo <dongbo4@xxxxxxxxxx>

In designware PCIe driver, the iatu0 is used for both CFG and IO accesses.
When sending CFGs to peripherals (e.g. lspci), iatu0 frequently switches
between CFG and IO alternatively.

A MEMORY probably be sent as an IOs by mistake. Considering the following
configurations:
MEMORY -> BASE_ADDR: 0xb4100000, LIMIT: 0xb4100FFF, TYPE=mem
CFG -> BASE_ADDR: 0xb4000000, LIMIT: 0xb4000FFF, TYPE=cfg
IO -> BASE_ADDR: 0xFFFFFFFF, LIMIT: 0xFFFFFFFE, TYPE=io

Suppose PCIe has just completed a CFG access, to switch back to IO, it set
the BASE_ADDR to 0xFFFFFFFF, LIMIT 0xFFFFFFFE and TYPE to io. When another
CFG comes, the BASE_ADDR is set to 0xb4000000 to switch to CFG. At this
moment, a MEMORY access shows up, since it matches with iatu0
(due to 0xb4000000 <= MEMORY BASE_ADDR <= MEMORY LIMIE <= 0xFFFFFFF), it
is treated as an IO access by mistake, then sent to perpheral.

This patch fixes the problem by exchanging the assignments of `MEMORYs'
and `CFGs/IOs', which assigning MEMEORYs to iatu0, CFGs and IOs to iatu1.

Signed-off-by: Dong Bo <dongbo4@xxxxxxxxxx>
---
drivers/pci/host/pcie-designware.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/pci/host/pcie-designware.c b/drivers/pci/host/pcie-designware.c
index aafd766..1bd88d9 100644
--- a/drivers/pci/host/pcie-designware.c
+++ b/drivers/pci/host/pcie-designware.c
@@ -599,11 +599,11 @@ static int dw_pcie_rd_other_conf(struct pcie_port *pp, struct pci_bus *bus,
va_cfg_base = pp->va_cfg1_base;
}
- dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX0,
+ dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX1,
type, cpu_addr,
busdev, cfg_size);
ret = dw_pcie_cfg_read(va_cfg_base + where, size, val);
- dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX0,
+ dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX1,
PCIE_ATU_TYPE_IO, pp->io_base,
pp->io_bus_addr, pp->io_size);
@@ -636,11 +636,11 @@ static int dw_pcie_wr_other_conf(struct pcie_port *pp, struct pci_bus *bus,
va_cfg_base = pp->va_cfg1_base;
}
- dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX0,
+ dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX1,
type, cpu_addr,
busdev, cfg_size);
ret = dw_pcie_cfg_write(va_cfg_base + where, size, val);
- dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX0,
+ dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX1,
PCIE_ATU_TYPE_IO, pp->io_base,
pp->io_bus_addr, pp->io_size);
@@ -779,7 +779,7 @@ void dw_pcie_setup_rc(struct pcie_port *pp)
* we should not program the ATU here.
*/
if (!pp->ops->rd_other_conf)
- dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX1,
+ dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX0,
PCIE_ATU_TYPE_MEM, pp->mem_base,
pp->mem_bus_addr, pp->mem_size);
-- 1.9.1


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