@@ -253,6 +253,25 @@ static void advk_pcie_wait_for_retrain(struct advk_pcie *pcie)
}
}
+static void advk_pcie_issue_perst(struct advk_pcie *pcie)
+{
+ u32 reg;
+
+ if (!pcie->reset_gpio)
+ return;
+
+ /* PERST does not work for some cards when link training is enabled */
+ reg = advk_readl(pcie, PCIE_CORE_CTRL0_REG);
+ reg &= ~LINK_TRAINING_EN;
+ advk_writel(pcie, reg, PCIE_CORE_CTRL0_REG);
+
+ /* 10ms delay is needed for some cards */
+ dev_info(&pcie->pdev->dev, "issuing PERST via reset GPIO for 10ms\n");
+ gpiod_set_value_cansleep(pcie->reset_gpio, 1);
+ usleep_range(10000, 11000);
+ gpiod_set_value_cansleep(pcie->reset_gpio, 0);
+}
+
static int advk_pcie_train_at_gen(struct advk_pcie *pcie, int gen)
{
int ret, neg_gen;
@@ -300,6 +319,21 @@ static void advk_pcie_train_link(struct advk_pcie *pcie)
struct device *dev = &pcie->pdev->dev;
int neg_gen = -1, gen;
+ /*
+ * Reset PCIe card via PERST# signal. Some cards are not detected
+ * during link training when they are in some non-initial state.
+ */
+ advk_pcie_issue_perst(pcie);
+
+ /*
+ * PERST# signal could have been asserted by pinctrl subsystem before
+ * probe() callback has been called or issued explicitly by reset gpio
+ * function advk_pcie_issue_perst(), making the endpoint going into
+ * fundamental reset. As required by PCI Express spec a delay for at
+ * least 100ms after such a reset before link training is needed.
+ */
+ msleep(PCI_PM_D3COLD_WAIT);
+
/*
* Try link training at link gen specified by device tree property
* 'max-link-speed'. If this fails, iteratively train at lower gen.
@@ -332,31 +366,10 @@ static void advk_pcie_train_link(struct advk_pcie *pcie)
dev_err(dev, "link never came up\n");
}
-static void advk_pcie_issue_perst(struct advk_pcie *pcie)
-{
- u32 reg;
-
- if (!pcie->reset_gpio)
- return;
-
- /* PERST does not work for some cards when link training is enabled */
- reg = advk_readl(pcie, PCIE_CORE_CTRL0_REG);
- reg &= ~LINK_TRAINING_EN;
- advk_writel(pcie, reg, PCIE_CORE_CTRL0_REG);
-
- /* 10ms delay is needed for some cards */
- dev_info(&pcie->pdev->dev, "issuing PERST via reset GPIO for 10ms\n");
- gpiod_set_value_cansleep(pcie->reset_gpio, 1);
- usleep_range(10000, 11000);
- gpiod_set_value_cansleep(pcie->reset_gpio, 0);
-}
-
static void advk_pcie_setup_hw(struct advk_pcie *pcie)
{
u32 reg;
- advk_pcie_issue_perst(pcie);
-
/* Enable TX */
reg = advk_readl(pcie, PCIE_CORE_REF_CLK_REG);
reg |= PCIE_CORE_REF_CLK_TX_ENABLE;
@@ -433,15 +446,6 @@ static void advk_pcie_setup_hw(struct advk_pcie *pcie)
reg |= PIO_CTRL_ADDR_WIN_DISABLE;
advk_writel(pcie, reg, PIO_CTRL);
- /*
- * PERST# signal could have been asserted by pinctrl subsystem before
- * probe() callback has been called or issued explicitly by reset gpio
- * function advk_pcie_issue_perst(), making the endpoint going into
- * fundamental reset. As required by PCI Express spec a delay for at
- * least 100ms after such a reset before link training is needed.
- */
- msleep(PCI_PM_D3COLD_WAIT);
-
advk_pcie_train_link(pcie);
/*