[PATCH] PCI: imx6: remove LTSSM disable workaround

[Lucas Stach]

This causes CPU hangs when the system is reset by the watchdog, as
the GPRs aren't cleared, but the clocks are back to disabled state.

If the bootloader uses PCIe, it must take care to bring it down
into a safe state, before passing control to the Linux kernel.
This is the only way to get a properly operating system at all
times and circumstances.

Signed-off-by: Lucas Stach <l.stach at pengutronix.de>
---
 drivers/pci/host/pci-imx6.c | 30 ------------------------------
 1 file changed, 30 deletions(-)

diff --git a/drivers/pci/host/pci-imx6.c b/drivers/pci/host/pci-imx6.c
index c8cefb078218..42c1987ffb3d 100644
--- a/drivers/pci/host/pci-imx6.c
+++ b/drivers/pci/host/pci-imx6.c
@@ -247,9 +247,6 @@ static int imx6q_pcie_abort_handler(unsigned long addr,
 
 static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie)
 {
-	struct pcie_port *pp = &imx6_pcie->pp;
-	u32 val, gpr1, gpr12;
-
 	switch (imx6_pcie->variant) {
 	case IMX6SX:
 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
@@ -266,33 +263,6 @@ static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie)
 				   IMX6Q_GPR1_PCIE_SW_RST);
 		break;
 	case IMX6Q:
-		/*
-		 * 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 = dw_pcie_readl_rc(pp, PCIE_PL_PFLR);
-			val &= ~PCIE_PL_PFLR_LINK_STATE_MASK;
-			val |= PCIE_PL_PFLR_FORCE_LINK;
-			dw_pcie_writel_rc(pp, PCIE_PL_PFLR, val);
-
-			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);
 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
-- 
2.11.0