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path: root/target/linux/imx6/patches-3.14/0055-pci_imx6_fix-boot-hang-when-link-already-enabled.patch
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Diffstat (limited to 'target/linux/imx6/patches-3.14/0055-pci_imx6_fix-boot-hang-when-link-already-enabled.patch')
-rw-r--r--target/linux/imx6/patches-3.14/0055-pci_imx6_fix-boot-hang-when-link-already-enabled.patch86
1 files changed, 0 insertions, 86 deletions
diff --git a/target/linux/imx6/patches-3.14/0055-pci_imx6_fix-boot-hang-when-link-already-enabled.patch b/target/linux/imx6/patches-3.14/0055-pci_imx6_fix-boot-hang-when-link-already-enabled.patch
deleted file mode 100644
index bae5a1f..0000000
--- a/target/linux/imx6/patches-3.14/0055-pci_imx6_fix-boot-hang-when-link-already-enabled.patch
+++ /dev/null
@@ -1,86 +0,0 @@
-This fixes a boot hang observed when the bootloader
-already enabled the PCIe link for it's own use. The
-fundamental problem is that Freescale forgot to wire
-up the core reset, so software doesn't have a sane way
-to get the core into a defined state.
-
-According to the DW PCIe core reference manual configuration
-of the core may only happen when the LTSSM is disabled, so
-this is one of the first things we need to do. Apparently
-this isn't safe to do when the LTSSM is in any other state
-than "detect" as we observe an instant machine hang when
-trying to do so while the link is already up.
-
-As a workaround force LTSSM into detect state right before
-hitting the disable switch.
-
-Reported-by: Fabio Estevam <fabio.estevam <at> freescale.com>
-Signed-off-by: Lucas Stach <l.stach <at> pengutronix.de>
-Acked-by: Tim Harvey <tharvey <at> gateworks.com>
---- a/drivers/pci/host/pci-imx6.c
-+++ b/drivers/pci/host/pci-imx6.c
-@@ -52,6 +52,9 @@ struct imx6_pcie {
-
- /* PCIe Port Logic registers (memory-mapped) */
- #define PL_OFFSET 0x700
-+#define PCIE_PL_PFLR (PL_OFFSET + 0x08)
-+#define PCIE_PL_PFLR_LINK_STATE_MASK (0x3f << 16)
-+#define PCIE_PL_PFLR_FORCE_LINK (1 << 15)
- #define PCIE_PHY_DEBUG_R0 (PL_OFFSET + 0x28)
- #define PCIE_PHY_DEBUG_R1 (PL_OFFSET + 0x2c)
- #define PCIE_PHY_DEBUG_R1_XMLH_LINK_IN_TRAINING (1 << 29)
-@@ -217,6 +220,31 @@ static int imx6q_pcie_abort_handler(unsi
- static int imx6_pcie_assert_core_reset(struct pcie_port *pp)
- {
- struct imx6_pcie *imx6_pcie = to_imx6_pcie(pp);
-+ u32 val, gpr1, gpr12;
-+
-+ /*
-+ * If the bootloader already enabled the link we need some special
-+ * handling to get the core back into a state where it is safe to
-+ * touch it for configuration. As there is no dedicated reset signal
-+ * wired up for MX6QDL, we need to manually force LTSSM into "detect"
-+ * state before completely disabling LTSSM, which is a prerequisite
-+ * for core configuration.
-+ * If both LTSSM_ENABLE and REF_SSP_ENABLE are active we have a strong
-+ * indication that the bootloader activated the link.
-+ */
-+ regmap_read(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1, &gpr1);
-+ regmap_read(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, &gpr12);
-+
-+ if ((gpr1 & IMX6Q_GPR1_PCIE_REF_CLK_EN) &&
-+ (gpr12 & IMX6Q_GPR12_PCIE_CTL_2)) {
-+ val = readl(pp->dbi_base + PCIE_PL_PFLR);
-+ val &= ~PCIE_PL_PFLR_LINK_STATE_MASK;
-+ val |= PCIE_PL_PFLR_FORCE_LINK;
-+ writel(val, pp->dbi_base + PCIE_PL_PFLR);
-+
-+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
-+ IMX6Q_GPR12_PCIE_CTL_2, 0 << 10);
-+ }
-
- regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
- IMX6Q_GPR1_PCIE_TEST_PD, 1 << 18);
-@@ -627,6 +655,14 @@ static int __init imx6_pcie_probe(struct
- return 0;
- }
-
-+static void imx6_pcie_shutdown(struct platform_device *pdev)
-+{
-+ struct imx6_pcie *imx6_pcie = platform_get_drvdata(pdev);
-+
-+ /* bring down link, so bootloader gets clean state in case of reboot */
-+ imx6_pcie_assert_core_reset(&imx6_pcie->pp);
-+}
-+
- static const struct of_device_id imx6_pcie_of_match[] = {
- { .compatible = "fsl,imx6q-pcie", },
- {},
-@@ -639,6 +675,7 @@ static struct platform_driver imx6_pcie_
- .owner = THIS_MODULE,
- .of_match_table = imx6_pcie_of_match,
- },
-+ .shutdown = imx6_pcie_shutdown,
- };
-
- /* Freescale PCIe driver does not allow module unload */