From c5c4d3a3f4a8c830cb514eb469a1025df2df0379 Mon Sep 17 00:00:00 2001 From: David Daney Date: Wed, 11 Jan 2017 11:22:11 -0800 Subject: PCI: thunder-pem: Add support for cn81xx and cn83xx SoCs The pci-thunder-pem driver was initially developed for cn88xx SoCs. The cn81xx and cn83xx members of the same family of SoCs have a slightly different configuration of interrupt resources in the PEM hardware, which prevents the INTA legacy interrupt source from functioning with the current driver. There are two fixes required: 1) Don't fixup the PME interrupt on the newer SoCs as it already has the proper value. 2) Report MSI-X Capability Table Size of 2 for the newer SoCs, so the core MSI-X code doesn't inadvertently clobber the INTA machinery that happens to reside immediately following the table. Signed-off-by: David Daney Signed-off-by: Bjorn Helgaas --- drivers/pci/host/pci-thunder-pem.c | 25 ++++++++++++++++++++----- 1 file changed, 20 insertions(+), 5 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/host/pci-thunder-pem.c b/drivers/pci/host/pci-thunder-pem.c index af722eb0ca75..52b5bdccf5f0 100644 --- a/drivers/pci/host/pci-thunder-pem.c +++ b/drivers/pci/host/pci-thunder-pem.c @@ -36,7 +36,7 @@ struct thunder_pem_pci { static int thunder_pem_bridge_read(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *val) { - u64 read_val; + u64 read_val, tmp_val; struct pci_config_window *cfg = bus->sysdata; struct thunder_pem_pci *pem_pci = (struct thunder_pem_pci *)cfg->priv; @@ -65,13 +65,28 @@ static int thunder_pem_bridge_read(struct pci_bus *bus, unsigned int devfn, read_val |= 0x00007000; /* Skip MSI CAP */ break; case 0x70: /* Express Cap */ - /* PME interrupt on vector 2*/ - read_val |= (2u << 25); + /* + * Change PME interrupt to vector 2 on T88 where it + * reads as 0, else leave it alone. + */ + if (!(read_val & (0x1f << 25))) + read_val |= (2u << 25); break; case 0xb0: /* MSI-X Cap */ - /* TableSize=4, Next Cap is EA */ + /* TableSize=2 or 4, Next Cap is EA */ read_val &= 0xc00000ff; - read_val |= 0x0003bc00; + /* + * If Express Cap(0x70) raw PME vector reads as 0 we are on + * T88 and TableSize is reported as 4, else TableSize + * is 2. + */ + writeq(0x70, pem_pci->pem_reg_base + PEM_CFG_RD); + tmp_val = readq(pem_pci->pem_reg_base + PEM_CFG_RD); + tmp_val >>= 32; + if (!(tmp_val & (0x1f << 25))) + read_val |= 0x0003bc00; + else + read_val |= 0x0001bc00; break; case 0xb4: /* Table offset=0, BIR=0 */ -- cgit