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pci: tegra: fix DM conversion issues on Tegra20

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Tegra20's PCIe controller has a couple of quirks. There are workarounds in
the driver for these, but they don't work after the DM conversion:

1) The PCI_CLASS value is wrong in HW.

This is worked around in pci_tegra_read_config() by patching up the value
read from that register. Pre-DM, the PCIe core always read this via a
16-bit access to the 16-bit offset 0xa. With DM, 32-bit accesses are used,
so we need to check for offset 0x8 instead. Mask the offset value back to
32-bit alignment to make this work in all cases.

2) Accessing devices other than dev 1 causes a data abort.

Pre-DM, this was worked around in pci_skip_dev(), which the PCIe core code
called during enumeration while iterating over a bus. The DM PCIe core
doesn't use this function. Instead, enhance tegra_pcie_conf_address() to
validate the bdf being accessed, and refuse to access invalid devices.
Since pci_skip_dev() isn't used, delete it.

I've also validated that both these WARs are only needed for Tegra20, by
testing on Tegra30/Cardhu and Tegra124/Jetson TKx. So, compile them in
conditionally.

Fixes: e81ca88451 ("dm: tegra: pci: Convert tegra boards to driver model for PCI")
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Warren <twarren@nvidia.com>
This commit is contained in:
Stephen Warren 2016-04-20 15:46:50 -06:00 committed by Tom Warren
parent d9b6f58efd
commit f5c6db84e7
1 changed files with 10 additions and 11 deletions
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21
drivers/pci/pci_tegra.c
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@ -275,12 +275,17 @@ static int tegra_pcie_conf_address(struct tegra_pcie *pcie, pci_dev_t bdf,
return 0;
}
}
return -EFAULT;
} else {
#ifdef CONFIG_TEGRA20
unsigned int dev = PCI_DEV(bdf);
if (dev != 0)
return -EFAULT;
#endif
*address = pcie->cs.start + tegra_pcie_conf_offset(bdf, where);
return 0;
}
return -EFAULT;
}
static int pci_tegra_read_config(struct udevice *bus, pci_dev_t bdf,
@ -299,13 +304,15 @@ static int pci_tegra_read_config(struct udevice *bus, pci_dev_t bdf,
value = readl(address);
#ifdef CONFIG_TEGRA20
/* fixup root port class */
if (PCI_BUS(bdf) == 0) {
if (offset == PCI_CLASS_REVISION) {
if ((offset & ~3) == PCI_CLASS_REVISION) {
value &= ~0x00ff0000;
value |= PCI_CLASS_BRIDGE_PCI << 16;
}
}
#endif
done:
*valuep = pci_conv_32_to_size(value, offset, size);
@ -1041,11 +1048,3 @@ U_BOOT_DRIVER(pci_tegra) = {
.probe = pci_tegra_probe,
.priv_auto_alloc_size = sizeof(struct tegra_pcie),
};
int pci_skip_dev(struct pci_controller *hose, pci_dev_t dev)
{
if (PCI_BUS(dev) != 0 && PCI_DEV(dev) > 0)
return 1;
return 0;
}