[PATCH u-boot-next 12/12] pci: sh7751: Fix access to config space via PCI_CONF1_ADDRESS() macro

Pali Rohár pali at kernel.org
Fri Nov 26 11:42:52 CET 2021


sh7751 platform uses standard format of Config Address for PCI
Configuration Mechanism #1.

Commit 72c2f4acd76f ("pci: sh7751: Convert to DM and DT probing") which did
conversion of PCI sh7751 driver to DM, broke access to config space as that
commit somehow swapped device and function bits in config address.

Fix all these issues by using new U-Boot macro PCI_CONF1_ADDRESS() which
calculates Config Address correctly.

Also remove nonsense function sh7751_pci_addr_valid() which was introduced
in commit 72c2f4acd76f ("pci: sh7751: Convert to DM and DT probing")
probably due to workarounded issues with mixing/swapping device and
function bits of config address which probably resulted in non-working
access to some devices. With correct composing of config address there
should not be such issue anymore.

Signed-off-by: Pali Rohár <pali at kernel.org>
Fixes: 72c2f4acd76f ("pci: sh7751: Convert to DM and DT probing")
Cc: Marek Vasut <marek.vasut+renesas at gmail.com>
---
 drivers/pci/pci_sh7751.c | 29 ++---------------------------
 1 file changed, 2 insertions(+), 27 deletions(-)

diff --git a/drivers/pci/pci_sh7751.c b/drivers/pci/pci_sh7751.c
index e110550c71c8..d514c040344c 100644
--- a/drivers/pci/pci_sh7751.c
+++ b/drivers/pci/pci_sh7751.c
@@ -74,33 +74,13 @@
 #define p4_in(addr)	(*addr)
 #define p4_out(data, addr) (*addr) = (data)
 
-static int sh7751_pci_addr_valid(pci_dev_t d, uint offset)
-{
-	if (PCI_FUNC(d))
-		return -EINVAL;
-
-	return 0;
-}
-
-static u32 get_bus_address(const struct udevice *dev, pci_dev_t bdf, u32 offset)
-{
-	return BIT(31) | (PCI_DEV(bdf) << 8) | (offset & ~3);
-}
-
 static int sh7751_pci_read_config(const struct udevice *dev, pci_dev_t bdf,
 				  uint offset, ulong *value,
 				  enum pci_size_t size)
 {
 	u32 addr, reg;
-	int ret;
 
-	ret = sh7751_pci_addr_valid(bdf, offset);
-	if (ret) {
-		*value = pci_get_ff(size);
-		return 0;
-	}
-
-	addr = get_bus_address(dev, bdf, offset);
+	addr = PCI_CONF1_ADDRESS(PCI_BUS(bdf), PCI_DEV(bdf), PCI_FUNC(bdf), offset);
 	p4_out(addr, SH7751_PCIPAR);
 	reg = p4_in(SH7751_PCIPDR);
 	*value = pci_conv_32_to_size(reg, offset, size);
@@ -113,13 +93,8 @@ static int sh7751_pci_write_config(struct udevice *dev, pci_dev_t bdf,
 				      enum pci_size_t size)
 {
 	u32 addr, reg, old;
-	int ret;
-
-	ret = sh7751_pci_addr_valid(bdf, offset);
-	if (ret)
-		return ret;
 
-	addr = get_bus_address(dev, bdf, offset);
+	addr = PCI_CONF1_ADDRESS(PCI_BUS(bdf), PCI_DEV(bdf), PCI_FUNC(bdf), offset);
 	p4_out(addr, SH7751_PCIPAR);
 	old = p4_in(SH7751_PCIPDR);
 	reg = pci_conv_size_to_32(old, value, offset, size);
-- 
2.20.1



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