[PATCH AUTOSEL 4.19 078/172] PCI: rcar: Fix incorrect programming of OB windows

From: Sasha Levin
Date: Wed Jun 17 2020 - 22:02:04 EST


From: Andrew Murray <andrew.murray@xxxxxxx>

[ Upstream commit 2b9f217433e31d125fb697ca7974d3de3ecc3e92 ]

The outbound windows (PCIEPAUR(x), PCIEPALR(x)) describe a mapping between
a CPU address (which is determined by the window number 'x') and a
programmed PCI address - Thus allowing the controller to translate CPU
accesses into PCI accesses.

However the existing code incorrectly writes the CPU address - lets fix
this by writing the PCI address instead.

For memory transactions, existing DT users describe a 1:1 identity mapping
and thus this change should have no effect. However the same isn't true for
I/O.

Link: https://lore.kernel.org/r/20191004132941.6660-1-andrew.murray@xxxxxxx
Fixes: c25da4778803 ("PCI: rcar: Add Renesas R-Car PCIe driver")
Tested-by: Marek Vasut <marek.vasut+renesas@xxxxxxxxx>
Signed-off-by: Andrew Murray <andrew.murray@xxxxxxx>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
Reviewed-by: Marek Vasut <marek.vasut+renesas@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/pci/controller/pcie-rcar.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/controller/pcie-rcar.c b/drivers/pci/controller/pcie-rcar.c
index 333ab6092f17..00296c5eacb9 100644
--- a/drivers/pci/controller/pcie-rcar.c
+++ b/drivers/pci/controller/pcie-rcar.c
@@ -335,11 +335,12 @@ static struct pci_ops rcar_pcie_ops = {
};

static void rcar_pcie_setup_window(int win, struct rcar_pcie *pcie,
- struct resource *res)
+ struct resource_entry *window)
{
/* Setup PCIe address space mappings for each resource */
resource_size_t size;
resource_size_t res_start;
+ struct resource *res = window->res;
u32 mask;

rcar_pci_write_reg(pcie, 0x00000000, PCIEPTCTLR(win));
@@ -353,9 +354,9 @@ static void rcar_pcie_setup_window(int win, struct rcar_pcie *pcie,
rcar_pci_write_reg(pcie, mask << 7, PCIEPAMR(win));

if (res->flags & IORESOURCE_IO)
- res_start = pci_pio_to_address(res->start);
+ res_start = pci_pio_to_address(res->start) - window->offset;
else
- res_start = res->start;
+ res_start = res->start - window->offset;

rcar_pci_write_reg(pcie, upper_32_bits(res_start), PCIEPAUR(win));
rcar_pci_write_reg(pcie, lower_32_bits(res_start) & ~0x7F,
@@ -384,7 +385,7 @@ static int rcar_pcie_setup(struct list_head *resource, struct rcar_pcie *pci)
switch (resource_type(res)) {
case IORESOURCE_IO:
case IORESOURCE_MEM:
- rcar_pcie_setup_window(i, pci, res);
+ rcar_pcie_setup_window(i, pci, win);
i++;
break;
case IORESOURCE_BUS:
--
2.25.1