pci: pcie_imx: Fix hang on mx6qp

PCI driver currently hangs on mx6qp.

Toggle the reset bit with the appropriate timings to fix the issue.

Based on the FSL kernel driver implementation.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Stefano Babic <sbabic@denx.de>

diff --git a/arch/arm/include/asm/arch-mx6/iomux.h b/arch/arm/include/asm/arch-mx6/iomux.h
index 9b3a91f..907cb40 100644 (file)
--- a/arch/arm/include/asm/arch-mx6/iomux.h
+++ b/arch/arm/include/asm/arch-mx6/iomux.h
@@ -18,6 +18,8 @@
 #define IOMUXC_GPR1_REF_SSP_EN                 (1 << 16)
 #define IOMUXC_GPR1_TEST_POWERDOWN             (1 << 18)
 
+#define IOMUXC_GPR1_PCIE_SW_RST                (1 << 29)
+
 /*
  * IOMUXC_GPR5 bit fields
  */

diff --git a/drivers/pci/pcie_imx.c b/drivers/pci/pcie_imx.c
index 1568f20..f1e189e 100644 (file)
--- a/drivers/pci/pcie_imx.c
+++ b/drivers/pci/pcie_imx.c
@@ -19,6 +19,7 @@
 #include <asm/io.h>
 #include <linux/sizes.h>
 #include <errno.h>
+#include <asm/arch/sys_proto.h>
 
 #define PCI_ACCESS_READ  0
 #define PCI_ACCESS_WRITE 1
@@ -430,6 +431,10 @@ static int imx_pcie_write_config(struct pci_controller *hose, pci_dev_t d,
 static int imx6_pcie_assert_core_reset(void)
 {
        struct iomuxc *iomuxc_regs = (struct iomuxc *)IOMUXC_BASE_ADDR;
+
+       if (is_mx6dqp())
+               setbits_le32(&iomuxc_regs->gpr[1], IOMUXC_GPR1_PCIE_SW_RST);
+
 #if defined(CONFIG_MX6SX)
        struct gpc *gpc_regs = (struct gpc *)GPC_BASE_ADDR;
 
@@ -536,6 +541,9 @@ static int imx6_pcie_deassert_core_reset(void)
 
        enable_pcie_clock();
 
+       if (is_mx6dqp())
+               clrbits_le32(&iomuxc_regs->gpr[1], IOMUXC_GPR1_PCIE_SW_RST);
+
        /*
         * Wait for the clock to settle a bit, when the clock are sourced
         * from the CPU, we need about 30 ms to settle.