summaryrefslogtreecommitdiffstats
path: root/kernel/drivers/pci/host/pci-imx6.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/drivers/pci/host/pci-imx6.c')
-rw-r--r--kernel/drivers/pci/host/pci-imx6.c108
1 files changed, 56 insertions, 52 deletions
diff --git a/kernel/drivers/pci/host/pci-imx6.c b/kernel/drivers/pci/host/pci-imx6.c
index fdb953677..9ce7cd148 100644
--- a/kernel/drivers/pci/host/pci-imx6.c
+++ b/kernel/drivers/pci/host/pci-imx6.c
@@ -47,6 +47,8 @@ struct imx6_pcie {
#define PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN2 0x2
#define PCIE_RC_LCR_MAX_LINK_SPEEDS_MASK 0xf
+#define PCIE_RC_LCSR 0x80
+
/* PCIe Port Logic registers (memory-mapped) */
#define PL_OFFSET 0x700
#define PCIE_PL_PFLR (PL_OFFSET + 0x08)
@@ -72,6 +74,7 @@ struct imx6_pcie {
/* PHY registers (not memory-mapped) */
#define PCIE_PHY_RX_ASIC_OUT 0x100D
+#define PCIE_PHY_RX_ASIC_OUT_VALID (1 << 0)
#define PHY_RX_OVRD_IN_LO 0x1005
#define PHY_RX_OVRD_IN_LO_RX_DATA_EN (1 << 5)
@@ -115,11 +118,7 @@ static int pcie_phy_wait_ack(void __iomem *dbi_base, int addr)
val = addr << PCIE_PHY_CTRL_DATA_LOC;
writel(val, dbi_base + PCIE_PHY_CTRL);
- ret = pcie_phy_poll_ack(dbi_base, 0);
- if (ret)
- return ret;
-
- return 0;
+ return pcie_phy_poll_ack(dbi_base, 0);
}
/* Read from the 16-bit PCIe PHY control registers (not memory-mapped) */
@@ -146,11 +145,7 @@ static int pcie_phy_read(void __iomem *dbi_base, int addr , int *data)
/* deassert Read signal */
writel(0x00, dbi_base + PCIE_PHY_CTRL);
- ret = pcie_phy_poll_ack(dbi_base, 0);
- if (ret)
- return ret;
-
- return 0;
+ return pcie_phy_poll_ack(dbi_base, 0);
}
static int pcie_phy_write(void __iomem *dbi_base, int addr, int data)
@@ -335,21 +330,36 @@ static void imx6_pcie_init_phy(struct pcie_port *pp)
static int imx6_pcie_wait_for_link(struct pcie_port *pp)
{
- int count = 200;
+ unsigned int retries;
- while (!dw_pcie_link_up(pp)) {
+ for (retries = 0; retries < 200; retries++) {
+ if (dw_pcie_link_up(pp))
+ return 0;
usleep_range(100, 1000);
- if (--count)
- continue;
-
- dev_err(pp->dev, "phy link never came up\n");
- dev_dbg(pp->dev, "DEBUG_R0: 0x%08x, DEBUG_R1: 0x%08x\n",
- readl(pp->dbi_base + PCIE_PHY_DEBUG_R0),
- readl(pp->dbi_base + PCIE_PHY_DEBUG_R1));
- return -EINVAL;
}
- return 0;
+ dev_err(pp->dev, "phy link never came up\n");
+ dev_dbg(pp->dev, "DEBUG_R0: 0x%08x, DEBUG_R1: 0x%08x\n",
+ readl(pp->dbi_base + PCIE_PHY_DEBUG_R0),
+ readl(pp->dbi_base + PCIE_PHY_DEBUG_R1));
+ return -EINVAL;
+}
+
+static int imx6_pcie_wait_for_speed_change(struct pcie_port *pp)
+{
+ u32 tmp;
+ unsigned int retries;
+
+ for (retries = 0; retries < 200; retries++) {
+ tmp = readl(pp->dbi_base + PCIE_LINK_WIDTH_SPEED_CONTROL);
+ /* Test if the speed change finished. */
+ if (!(tmp & PORT_LOGIC_SPEED_CHANGE))
+ return 0;
+ usleep_range(100, 1000);
+ }
+
+ dev_err(pp->dev, "Speed change timeout\n");
+ return -EINVAL;
}
static irqreturn_t imx6_pcie_msi_handler(int irq, void *arg)
@@ -359,11 +369,11 @@ static irqreturn_t imx6_pcie_msi_handler(int irq, void *arg)
return dw_handle_msi_irq(pp);
}
-static int imx6_pcie_start_link(struct pcie_port *pp)
+static int imx6_pcie_establish_link(struct pcie_port *pp)
{
struct imx6_pcie *imx6_pcie = to_imx6_pcie(pp);
- uint32_t tmp;
- int ret, count;
+ u32 tmp;
+ int ret;
/*
* Force Gen1 operation when starting the link. In case the link is
@@ -397,29 +407,22 @@ static int imx6_pcie_start_link(struct pcie_port *pp)
tmp |= PORT_LOGIC_SPEED_CHANGE;
writel(tmp, pp->dbi_base + PCIE_LINK_WIDTH_SPEED_CONTROL);
- count = 200;
- while (count--) {
- tmp = readl(pp->dbi_base + PCIE_LINK_WIDTH_SPEED_CONTROL);
- /* Test if the speed change finished. */
- if (!(tmp & PORT_LOGIC_SPEED_CHANGE))
- break;
- usleep_range(100, 1000);
+ ret = imx6_pcie_wait_for_speed_change(pp);
+ if (ret) {
+ dev_err(pp->dev, "Failed to bring link up!\n");
+ return ret;
}
/* Make sure link training is finished as well! */
- if (count)
- ret = imx6_pcie_wait_for_link(pp);
- else
- ret = -EINVAL;
-
+ ret = imx6_pcie_wait_for_link(pp);
if (ret) {
dev_err(pp->dev, "Failed to bring link up!\n");
- } else {
- tmp = readl(pp->dbi_base + 0x80);
- dev_dbg(pp->dev, "Link up, Gen=%i\n", (tmp >> 16) & 0xf);
+ return ret;
}
- return ret;
+ tmp = readl(pp->dbi_base + PCIE_RC_LCSR);
+ dev_dbg(pp->dev, "Link up, Gen=%i\n", (tmp >> 16) & 0xf);
+ return 0;
}
static void imx6_pcie_host_init(struct pcie_port *pp)
@@ -432,7 +435,7 @@ static void imx6_pcie_host_init(struct pcie_port *pp)
dw_pcie_setup_rc(pp);
- imx6_pcie_start_link(pp);
+ imx6_pcie_establish_link(pp);
if (IS_ENABLED(CONFIG_PCI_MSI))
dw_pcie_msi_init(pp);
@@ -440,19 +443,19 @@ static void imx6_pcie_host_init(struct pcie_port *pp)
static void imx6_pcie_reset_phy(struct pcie_port *pp)
{
- uint32_t temp;
+ u32 tmp;
- pcie_phy_read(pp->dbi_base, PHY_RX_OVRD_IN_LO, &temp);
- temp |= (PHY_RX_OVRD_IN_LO_RX_DATA_EN |
- PHY_RX_OVRD_IN_LO_RX_PLL_EN);
- pcie_phy_write(pp->dbi_base, PHY_RX_OVRD_IN_LO, temp);
+ pcie_phy_read(pp->dbi_base, PHY_RX_OVRD_IN_LO, &tmp);
+ tmp |= (PHY_RX_OVRD_IN_LO_RX_DATA_EN |
+ PHY_RX_OVRD_IN_LO_RX_PLL_EN);
+ pcie_phy_write(pp->dbi_base, PHY_RX_OVRD_IN_LO, tmp);
usleep_range(2000, 3000);
- pcie_phy_read(pp->dbi_base, PHY_RX_OVRD_IN_LO, &temp);
- temp &= ~(PHY_RX_OVRD_IN_LO_RX_DATA_EN |
+ pcie_phy_read(pp->dbi_base, PHY_RX_OVRD_IN_LO, &tmp);
+ tmp &= ~(PHY_RX_OVRD_IN_LO_RX_DATA_EN |
PHY_RX_OVRD_IN_LO_RX_PLL_EN);
- pcie_phy_write(pp->dbi_base, PHY_RX_OVRD_IN_LO, temp);
+ pcie_phy_write(pp->dbi_base, PHY_RX_OVRD_IN_LO, tmp);
}
static int imx6_pcie_link_up(struct pcie_port *pp)
@@ -501,7 +504,7 @@ static int imx6_pcie_link_up(struct pcie_port *pp)
pcie_phy_read(pp->dbi_base, PCIE_PHY_RX_ASIC_OUT, &rx_valid);
debug_r0 = readl(pp->dbi_base + PCIE_PHY_DEBUG_R0);
- if (rx_valid & 0x01)
+ if (rx_valid & PCIE_PHY_RX_ASIC_OUT_VALID)
return 0;
if ((debug_r0 & 0x3f) != 0x0d)
@@ -534,10 +537,11 @@ static int __init imx6_add_pcie_port(struct pcie_port *pp,
ret = devm_request_irq(&pdev->dev, pp->msi_irq,
imx6_pcie_msi_handler,
- IRQF_SHARED, "mx6-pcie-msi", pp);
+ IRQF_SHARED | IRQF_NO_THREAD,
+ "mx6-pcie-msi", pp);
if (ret) {
dev_err(&pdev->dev, "failed to request MSI irq\n");
- return -ENODEV;
+ return ret;
}
}