diff options
Diffstat (limited to 'target/linux/layerscape/patches-5.4/812-pcie-0014-PCI-mobiveil-ls_pcie_g4-add-Workaround-for-A-011451.patch')
-rw-r--r-- | target/linux/layerscape/patches-5.4/812-pcie-0014-PCI-mobiveil-ls_pcie_g4-add-Workaround-for-A-011451.patch | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/target/linux/layerscape/patches-5.4/812-pcie-0014-PCI-mobiveil-ls_pcie_g4-add-Workaround-for-A-011451.patch b/target/linux/layerscape/patches-5.4/812-pcie-0014-PCI-mobiveil-ls_pcie_g4-add-Workaround-for-A-011451.patch new file mode 100644 index 0000000000..5486bdd003 --- /dev/null +++ b/target/linux/layerscape/patches-5.4/812-pcie-0014-PCI-mobiveil-ls_pcie_g4-add-Workaround-for-A-011451.patch @@ -0,0 +1,73 @@ +From 5f1673ff67d5e8acf590fb5a4cc2d0d5d4115927 Mon Sep 17 00:00:00 2001 +From: Hou Zhiqiang <Zhiqiang.Hou@nxp.com> +Date: Tue, 6 Nov 2018 10:14:57 +0800 +Subject: [PATCH] PCI: mobiveil: ls_pcie_g4: add Workaround for A-011451 + +When LX2 PCIe controller is sending multiple split completions and +ACK latency expires indicating that ACK should be send at priority. +But because of large number of split completions and FC update DLLP, +the controller does not give priority to ACK transmission. This +results into ACK latency timer timeout error at the link partner and +the pending TLPs are replayed by the link partner again. + +Workaround: +1. Reduce the ACK latency timeout value to a very small value. +2. Restrict the number of completions from the LX2 PCIe controller + to 1, by changing the Max Read Request Size (MRRS) of link partner + to the same value as Max Packet size (MPS). + +This patch implemented part 1, the part 2 can be set by kernel parameter +'pci=pcie_bus_perf' + +This ERRATA is only for LX2160A Rev1.0, and it will be fixed +in Rev2.0. + +Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@nxp.com> +--- + drivers/pci/controller/mobiveil/pcie-layerscape-gen4.c | 15 +++++++++++++++ + drivers/pci/controller/mobiveil/pcie-mobiveil.h | 4 ++++ + 2 files changed, 19 insertions(+) + +--- a/drivers/pci/controller/mobiveil/pcie-layerscape-gen4.c ++++ b/drivers/pci/controller/mobiveil/pcie-layerscape-gen4.c +@@ -80,12 +80,27 @@ static bool ls_pcie_g4_is_bridge(struct + return header_type == PCI_HEADER_TYPE_BRIDGE; + } + ++static void workaround_A011451(struct ls_pcie_g4 *pcie) ++{ ++ struct mobiveil_pcie *mv_pci = &pcie->pci; ++ u32 val; ++ ++ /* Set ACK latency timeout */ ++ val = csr_readl(mv_pci, GPEX_ACK_REPLAY_TO); ++ val &= ~(ACK_LAT_TO_VAL_MASK << ACK_LAT_TO_VAL_SHIFT); ++ val |= (4 << ACK_LAT_TO_VAL_SHIFT); ++ csr_writel(mv_pci, val, GPEX_ACK_REPLAY_TO); ++} ++ + static int ls_pcie_g4_host_init(struct mobiveil_pcie *pci) + { + struct ls_pcie_g4 *pcie = to_ls_pcie_g4(pci); + + pcie->rev = csr_readb(pci, PCI_REVISION_ID); + ++ if (pcie->rev == REV_1_0) ++ workaround_A011451(pcie); ++ + return 0; + } + +--- a/drivers/pci/controller/mobiveil/pcie-mobiveil.h ++++ b/drivers/pci/controller/mobiveil/pcie-mobiveil.h +@@ -86,6 +86,10 @@ + #define PAB_AXI_AMAP_PEX_WIN_H(win) PAB_REG_ADDR(0x0bac, win) + #define PAB_INTP_AXI_PIO_CLASS 0x474 + ++#define GPEX_ACK_REPLAY_TO 0x438 ++#define ACK_LAT_TO_VAL_MASK 0x1fff ++#define ACK_LAT_TO_VAL_SHIFT 0 ++ + #define PAB_PEX_AMAP_CTRL(win) PAB_REG_ADDR(0x4ba0, win) + #define AMAP_CTRL_EN_SHIFT 0 + #define AMAP_CTRL_TYPE_SHIFT 1 |