sb600: Implement EHCI workaround

Linux implements it itself, but older Linuxes and other systems
might not. Without this, the host controller might not respond
to drivers.

Change-Id: I4ff0e3683c02e7aa00d188428847c64c4c5d589d
Signed-off-by: Patrick Georgi <patrick.georgi@secunet.com>
Reviewed-on: http://review.coreboot.org/345
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

diff --git a/src/southbridge/amd/sb600/usb.c b/src/southbridge/amd/sb600/usb.c
index 7539f083c640be1f3deef3068230e040df7d0f92..7ff8f5c9a4e43dc6702a4d637972618d862becb7 100644 (file)
--- a/src/southbridge/amd/sb600/usb.c
+++ b/src/southbridge/amd/sb600/usb.c
@@ -119,6 +119,11 @@ static void usb_init2(struct device *dev)
        dword &= ~(1 << 28);
        pci_write_config32(dev, 0x50, dword);
 
+       /* EHCI Erratum (adapted from Linux) */
+       dword = pci_read_config32(dev, 0x53);
+       dword |= (1 << 3);
+       pci_write_config32(dev, 0x53, dword);
+
        /* RPR5.14 Disable USB PHY PLL Reset signal to come from ACPI */
        byte = pci_read_config8(dev, 0x54);
        byte &= ~(1 << 0);