From c0a4e6b889a702cc2c8375619ce7b093f6b3b1de Mon Sep 17 00:00:00 2001 From: Yuanquan Chen Date: Mon, 26 Nov 2012 23:49:45 +0000 Subject: powerpc/p4080ds: fix PCI-e x8 link training down failure Due to SerDes configuration error, if we set the PCI-e controller link width as x8 in RCW and add a narrower width(such as x4, x2 or x1) PCI-e device to PCI-e slot, it fails to train down to the PCI-e device's link width. According to p4080ds errata PCIe-A003, we reset the PCI-e controller link width to x4 in u-boot. Then it can train down to x2 or x1 width to make the PCI-e link between RC and EP. Signed-off-by: Yuanquan Chen Signed-off-by: Andy Fleming --- drivers/pci/fsl_pci_init.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) (limited to 'drivers') diff --git a/drivers/pci/fsl_pci_init.c b/drivers/pci/fsl_pci_init.c index 48ae163..77ac1f7 100644 --- a/drivers/pci/fsl_pci_init.c +++ b/drivers/pci/fsl_pci_init.c @@ -470,6 +470,28 @@ void fsl_pci_init(struct pci_controller *hose, struct fsl_pci_info *pci_info) } #endif +#ifdef CONFIG_SYS_P4080_ERRATUM_PCIE_A003 + if (enabled == 0) { + serdes_corenet_t *srds_regs = (void *)CONFIG_SYS_FSL_CORENET_SERDES_ADDR; + temp32 = in_be32(&srds_regs->srdspccr0); + + if ((temp32 >> 28) == 3) { + int i; + + out_be32(&srds_regs->srdspccr0, 2 << 28); + setbits_be32(&pci->pdb_stat, 0x08000000); + in_be32(&pci->pdb_stat); + udelay(100); + clrbits_be32(&pci->pdb_stat, 0x08000000); + asm("sync;isync"); + for (i=0; i < 100 && ltssm < PCI_LTSSM_L0; i++) { + pci_hose_read_config_word(hose, dev, PCI_LTSSM, <ssm); + udelay(1000); + } + enabled = ltssm >= PCI_LTSSM_L0; + } + } +#endif if (!enabled) { /* Let the user know there's no PCIe link */ printf("no link, regs @ 0x%lx\n", pci_info->regs); -- cgit v1.1