diff options
Diffstat (limited to 'target/linux/ipq806x/patches-5.4/0071-8-pcie-qcom-Fixed-pcie_phy_clk-branch-issue.patch')
| -rw-r--r-- | target/linux/ipq806x/patches-5.4/0071-8-pcie-qcom-Fixed-pcie_phy_clk-branch-issue.patch | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/target/linux/ipq806x/patches-5.4/0071-8-pcie-qcom-Fixed-pcie_phy_clk-branch-issue.patch b/target/linux/ipq806x/patches-5.4/0071-8-pcie-qcom-Fixed-pcie_phy_clk-branch-issue.patch new file mode 100644 index 0000000000..7cbeb3bed7 --- /dev/null +++ b/target/linux/ipq806x/patches-5.4/0071-8-pcie-qcom-Fixed-pcie_phy_clk-branch-issue.patch @@ -0,0 +1,91 @@ +From b74bab6186131eea09459eedf5d737645a3559c9 Mon Sep 17 00:00:00 2001 +From: Abhishek Sahu <absahu@codeaurora.org> +Date: Thu, 22 Dec 2016 11:18:45 +0530 +Subject: pcie: qcom: Fixed pcie_phy_clk branch issue + +Following backtraces are observed in PCIe deinit operation. + + Hardware name: Qualcomm (Flattened Device Tree) + (unwind_backtrace) from [] (show_stack+0x10/0x14) + (show_stack) from [] (dump_stack+0x84/0x98) + (dump_stack) from [] (warn_slowpath_common+0x9c/0xb8) + (warn_slowpath_common) from [] (warn_slowpath_fmt+0x30/0x40) + (warn_slowpath_fmt) from [] (clk_branch_wait+0x114/0x120) + (clk_branch_wait) from [] (clk_core_disable+0xd0/0x1f4) + (clk_core_disable) from [] (clk_disable+0x24/0x30) + (clk_disable) from [] (qcom_pcie_deinit_v0+0x6c/0xb8) + (qcom_pcie_deinit_v0) from [] (qcom_pcie_host_init+0xe0/0xe8) + (qcom_pcie_host_init) from [] (dw_pcie_host_init+0x3b0/0x538) + (dw_pcie_host_init) from [] (qcom_pcie_probe+0x20c/0x2e4) + +pcie_phy_clk is generated for PCIe controller itself and the +GCC controls its branch operation. This error is coming since +the assert operations turn off the parent clock before branch +clock. Now this patch moves clk_disable_unprepare before assert +operations. + +Similarly, during probe function, the clock branch operation +should be done after dessert operation. Currently, it does not +generate any error since bootloader enables the pcie_phy_clk +but the same error is coming during probe, if bootloader +disables pcie_phy_clk. + +Change-Id: Ib29c154d10eb64363d9cc982ce5fd8107af5627d +Signed-off-by: Abhishek Sahu <absahu@codeaurora.org> +--- + drivers/pci/host/pcie-qcom.c | 16 +++++++--------- + 1 file changed, 7 insertions(+), 9 deletions(-) + +--- a/drivers/pci/controller/dwc/pcie-qcom.c ++++ b/drivers/pci/controller/dwc/pcie-qcom.c +@@ -393,6 +393,7 @@ static void qcom_pcie_deinit_2_1_0(struc + { + struct qcom_pcie_resources_2_1_0 *res = &pcie->res.v2_1_0; + ++ clk_disable_unprepare(res->phy_clk); + reset_control_assert(res->pci_reset); + reset_control_assert(res->axi_reset); + reset_control_assert(res->ahb_reset); +@@ -401,7 +402,6 @@ static void qcom_pcie_deinit_2_1_0(struc + reset_control_assert(res->ext_reset); + clk_disable_unprepare(res->iface_clk); + clk_disable_unprepare(res->core_clk); +- clk_disable_unprepare(res->phy_clk); + clk_disable_unprepare(res->aux_clk); + clk_disable_unprepare(res->ref_clk); + regulator_bulk_disable(ARRAY_SIZE(res->supplies), res->supplies); +@@ -444,12 +444,6 @@ static int qcom_pcie_init_2_1_0(struct q + goto err_clk_core; + } + +- ret = clk_prepare_enable(res->phy_clk); +- if (ret) { +- dev_err(dev, "cannot prepare/enable phy clock\n"); +- goto err_clk_phy; +- } +- + ret = clk_prepare_enable(res->aux_clk); + if (ret) { + dev_err(dev, "cannot prepare/enable aux clock\n"); +@@ -513,6 +507,12 @@ static int qcom_pcie_init_2_1_0(struct q + return ret; + } + ++ ret = clk_prepare_enable(res->phy_clk); ++ if (ret) { ++ dev_err(dev, "cannot prepare/enable phy clock\n"); ++ goto err_deassert_ahb; ++ } ++ + /* wait for clock acquisition */ + usleep_range(1000, 1500); + if (pcie->force_gen1) { +@@ -538,8 +538,6 @@ err_deassert_ahb: + err_clk_ref: + clk_disable_unprepare(res->aux_clk); + err_clk_aux: +- clk_disable_unprepare(res->phy_clk); +-err_clk_phy: + clk_disable_unprepare(res->core_clk); + err_clk_core: + clk_disable_unprepare(res->iface_clk); |