diff options
| author |   Stanimir Varbanov <stanimir.varbanov@linaro.org> | 2015-12-18 14:38:55 +0200 |
|---|---|---|
| committer |   Bjorn Helgaas <bhelgaas@google.com> | 2016-01-05 11:50:21 -0600 |
| commit | 17209dfb35a228e597a387bfc83b68093b247f78 (patch) | |
| tree | e1285e1c10cd9eade67b3b2b81ceea959c5a68d3 /drivers/pci | |
| parent | Linux 4.4-rc2 (diff) | |
| download | linux-dev-17209dfb35a228e597a387bfc83b68093b247f78.tar.xz linux-dev-17209dfb35a228e597a387bfc83b68093b247f78.zip | |
PCI: designware: Ensure ATU is enabled before IO/conf space accesses
Read back the ATU CR2 register to ensure ATU programming is effective
before any subsequent I/O or config space accesses.
Without this, PCI device enumeration is unreliable.
[bhelgaas: changelog, comment]
Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Pratyush Anand <pratyush.anand@gmail.com>
Diffstat (limited to 'drivers/pci')
| -rw-r--r-- | drivers/pci/host/pcie-designware.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/pci/host/pcie-designware.c b/drivers/pci/host/pcie-designware.c index 540f077c37ea..7353371b3f15 100644 --- a/drivers/pci/host/pcie-designware.c +++ b/drivers/pci/host/pcie-designware.c @@ -154,6 +154,8 @@ static int dw_pcie_wr_own_conf(struct pcie_port *pp, int where, int size, static void dw_pcie_prog_outbound_atu(struct pcie_port *pp, int index, int type, u64 cpu_addr, u64 pci_addr, u32 size) { + u32 val; + dw_pcie_writel_rc(pp, PCIE_ATU_REGION_OUTBOUND | index, PCIE_ATU_VIEWPORT); dw_pcie_writel_rc(pp, lower_32_bits(cpu_addr), PCIE_ATU_LOWER_BASE); @@ -164,6 +166,12 @@ static void dw_pcie_prog_outbound_atu(struct pcie_port *pp, int index, dw_pcie_writel_rc(pp, upper_32_bits(pci_addr), PCIE_ATU_UPPER_TARGET); dw_pcie_writel_rc(pp, type, PCIE_ATU_CR1); dw_pcie_writel_rc(pp, PCIE_ATU_ENABLE, PCIE_ATU_CR2); + + /* + * Make sure ATU enable takes effect before any subsequent config + * and I/O accesses. + */ + dw_pcie_readl_rc(pp, PCIE_ATU_CR2, &val); } static struct irq_chip dw_msi_irq_chip = { |