[PATCH v4 2/2] PCI: qcom: Move all DBI register accesses after phy_power_on()

Robert Marko
2022-06-24T10:44:36Z

IPQ8074 requires the PHY to be powered on before accessing DBI registers.
It's not clear whether other variants have the same dependency, but there
seems to be no reason for them to be different, so move all the DBI
accesses from .init() to .post_init() so they are all after phy_power_on().

Signed-off-by: Robert Marko <robimarko@gmail.com>
---
Changes in v4:
* Move 2.7.0 accesses as well
* Correct title and description (Bjorn)
---
drivers/pci/controller/dwc/pcie-qcom.c | 215 ++++++++++++++-----------
1 file changed, 119 insertions(+), 96 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
index 24708d5d817d..f1a156052fe7 100644
--- a/drivers/pci/controller/dwc/pcie-qcom.c
+++ b/drivers/pci/controller/dwc/pcie-qcom.c
@@ -348,8 +348,6 @@ static int qcom_pcie_init_2_1_0(struct qcom_pcie *pcie)
struct qcom_pcie_resources_2_1_0 *res = &pcie->res.v2_1_0;
struct dw_pcie *pci = pcie->pci;
struct device *dev = pci->dev;
- struct device_node *node = dev->of_node;
- u32 val;
int ret;

/* reset the PCIe interface as uboot can leave it undefined state */
@@ -360,8 +358,6 @@ static int qcom_pcie_init_2_1_0(struct qcom_pcie *pcie)
reset_control_assert(res->ext_reset);
reset_control_assert(res->phy_reset);

- writel(1, pcie->parf + PCIE20_PARF_PHY_CTRL);
-
ret = regulator_bulk_enable(ARRAY_SIZE(res->supplies), res->supplies);
if (ret < 0) {
dev_err(dev, "cannot enable regulators\n");
@@ -408,6 +404,35 @@ static int qcom_pcie_init_2_1_0(struct qcom_pcie *pcie)
if (ret)
goto err_clks;

+ return 0;
+
+err_clks:
+ reset_control_assert(res->axi_reset);
+err_deassert_axi:
+ reset_control_assert(res->por_reset);
+err_deassert_por:
+ reset_control_assert(res->pci_reset);
+err_deassert_pci:
+ reset_control_assert(res->phy_reset);
+err_deassert_phy:
+ reset_control_assert(res->ext_reset);
+err_deassert_ext:
+ reset_control_assert(res->ahb_reset);
+err_deassert_ahb:
+ regulator_bulk_disable(ARRAY_SIZE(res->supplies), res->supplies);
+
+ return ret;
+}
+
+static int qcom_pcie_post_init_2_1_0(struct qcom_pcie *pcie)
+{
+ struct dw_pcie *pci = pcie->pci;
+ struct device *dev = pci->dev;
+ struct device_node *node = dev->of_node;
+ u32 val;
+
+ writel(1, pcie->parf + PCIE20_PARF_PHY_CTRL);
+
/* enable PCIe clocks and resets */
val = readl(pcie->parf + PCIE20_PARF_PHY_CTRL);
val &= ~BIT(0);
@@ -451,23 +476,6 @@ static int qcom_pcie_init_2_1_0(struct qcom_pcie *pcie)
pci->dbi_base + PCIE20_AXI_MSTR_RESP_COMP_CTRL1);

return 0;
-
-err_clks:
- reset_control_assert(res->axi_reset);
-err_deassert_axi:
- reset_control_assert(res->por_reset);
-err_deassert_por:
- reset_control_assert(res->pci_reset);
-err_deassert_pci:
- reset_control_assert(res->phy_reset);
-err_deassert_phy:
- reset_control_assert(res->ext_reset);
-err_deassert_ext:
- reset_control_assert(res->ahb_reset);
-err_deassert_ahb:
- regulator_bulk_disable(ARRAY_SIZE(res->supplies), res->supplies);
-
- return ret;
}

static int qcom_pcie_get_resources_1_0_0(struct qcom_pcie *pcie)
@@ -555,16 +563,6 @@ static int qcom_pcie_init_1_0_0(struct qcom_pcie *pcie)
goto err_slave;
}

- /* change DBI base address */
- writel(0, pcie->parf + PCIE20_PARF_DBI_BASE_ADDR);
-
- if (IS_ENABLED(CONFIG_PCI_MSI)) {
- u32 val = readl(pcie->parf + PCIE20_PARF_AXI_MSTR_WR_ADDR_HALT);
-
- val |= BIT(31);
- writel(val, pcie->parf + PCIE20_PARF_AXI_MSTR_WR_ADDR_HALT);
- }
-
return 0;
err_slave:
clk_disable_unprepare(res->slave_bus);
@@ -580,6 +578,22 @@ static int qcom_pcie_init_1_0_0(struct qcom_pcie *pcie)
return ret;
}

+static int qcom_pcie_post_init_1_0_0(struct qcom_pcie *pcie)
+{
+
+ /* change DBI base address */
+ writel(0, pcie->parf + PCIE20_PARF_DBI_BASE_ADDR);
+
+ if (IS_ENABLED(CONFIG_PCI_MSI)) {
+ u32 val = readl(pcie->parf + PCIE20_PARF_AXI_MSTR_WR_ADDR_HALT);
+
+ val |= BIT(31);
+ writel(val, pcie->parf + PCIE20_PARF_AXI_MSTR_WR_ADDR_HALT);
+ }
+
+ return 0;
+}
+
static void qcom_pcie_2_3_2_ltssm_enable(struct qcom_pcie *pcie)
{
u32 val;
@@ -648,7 +662,6 @@ static int qcom_pcie_init_2_3_2(struct qcom_pcie *pcie)
struct qcom_pcie_resources_2_3_2 *res = &pcie->res.v2_3_2;
struct dw_pcie *pci = pcie->pci;
struct device *dev = pci->dev;
- u32 val;
int ret;

ret = regulator_bulk_enable(ARRAY_SIZE(res->supplies), res->supplies);
@@ -681,27 +694,6 @@ static int qcom_pcie_init_2_3_2(struct qcom_pcie *pcie)
goto err_slave_clk;
}

- /* enable PCIe clocks and resets */
- val = readl(pcie->parf + PCIE20_PARF_PHY_CTRL);
- val &= ~BIT(0);
- writel(val, pcie->parf + PCIE20_PARF_PHY_CTRL);
-
- /* change DBI base address */
- writel(0, pcie->parf + PCIE20_PARF_DBI_BASE_ADDR);
-
- /* MAC PHY_POWERDOWN MUX DISABLE */
- val = readl(pcie->parf + PCIE20_PARF_SYS_CTRL);
- val &= ~BIT(29);
- writel(val, pcie->parf + PCIE20_PARF_SYS_CTRL);
-
- val = readl(pcie->parf + PCIE20_PARF_MHI_CLOCK_RESET_CTRL);
- val |= BIT(4);
- writel(val, pcie->parf + PCIE20_PARF_MHI_CLOCK_RESET_CTRL);
-
- val = readl(pcie->parf + PCIE20_PARF_AXI_MSTR_WR_ADDR_HALT_V2);
- val |= BIT(31);
- writel(val, pcie->parf + PCIE20_PARF_AXI_MSTR_WR_ADDR_HALT_V2);
-
return 0;

err_slave_clk:
@@ -722,8 +714,30 @@ static int qcom_pcie_post_init_2_3_2(struct qcom_pcie *pcie)
struct qcom_pcie_resources_2_3_2 *res = &pcie->res.v2_3_2;
struct dw_pcie *pci = pcie->pci;
struct device *dev = pci->dev;
+ u32 val;
int ret;

+ /* enable PCIe clocks and resets */
+ val = readl(pcie->parf + PCIE20_PARF_PHY_CTRL);
+ val &= ~BIT(0);
+ writel(val, pcie->parf + PCIE20_PARF_PHY_CTRL);
+
+ /* change DBI base address */
+ writel(0, pcie->parf + PCIE20_PARF_DBI_BASE_ADDR);
+
+ /* MAC PHY_POWERDOWN MUX DISABLE */
+ val = readl(pcie->parf + PCIE20_PARF_SYS_CTRL);
+ val &= ~BIT(29);
+ writel(val, pcie->parf + PCIE20_PARF_SYS_CTRL);
+
+ val = readl(pcie->parf + PCIE20_PARF_MHI_CLOCK_RESET_CTRL);
+ val |= BIT(4);
+ writel(val, pcie->parf + PCIE20_PARF_MHI_CLOCK_RESET_CTRL);
+
+ val = readl(pcie->parf + PCIE20_PARF_AXI_MSTR_WR_ADDR_HALT_V2);
+ val |= BIT(31);
+ writel(val, pcie->parf + PCIE20_PARF_AXI_MSTR_WR_ADDR_HALT_V2);
+
ret = clk_prepare_enable(res->pipe_clk);
if (ret) {
dev_err(dev, "cannot prepare/enable pipe clock\n");
@@ -837,7 +851,6 @@ static int qcom_pcie_init_2_4_0(struct qcom_pcie *pcie)
struct qcom_pcie_resources_2_4_0 *res = &pcie->res.v2_4_0;
struct dw_pcie *pci = pcie->pci;
struct device *dev = pci->dev;
- u32 val;
int ret;

ret = reset_control_assert(res->axi_m_reset);
@@ -962,6 +975,33 @@ static int qcom_pcie_init_2_4_0(struct qcom_pcie *pcie)
if (ret)
goto err_clks;

+ return 0;
+
+err_clks:
+ reset_control_assert(res->ahb_reset);
+err_rst_ahb:
+ reset_control_assert(res->pwr_reset);
+err_rst_pwr:
+ reset_control_assert(res->axi_s_reset);
+err_rst_axi_s:
+ reset_control_assert(res->axi_m_sticky_reset);
+err_rst_axi_m_sticky:
+ reset_control_assert(res->axi_m_reset);
+err_rst_axi_m:
+ reset_control_assert(res->pipe_sticky_reset);
+err_rst_pipe_sticky:
+ reset_control_assert(res->pipe_reset);
+err_rst_pipe:
+ reset_control_assert(res->phy_reset);
+err_rst_phy:
+ reset_control_assert(res->phy_ahb_reset);
+ return ret;
+}
+
+static int qcom_pcie_post_init_2_4_0(struct qcom_pcie *pcie)
+{
+ u32 val;
+
/* enable PCIe clocks and resets */
val = readl(pcie->parf + PCIE20_PARF_PHY_CTRL);
val &= ~BIT(0);
@@ -984,26 +1024,6 @@ static int qcom_pcie_init_2_4_0(struct qcom_pcie *pcie)
writel(val, pcie->parf + PCIE20_PARF_AXI_MSTR_WR_ADDR_HALT_V2);

return 0;
-
-err_clks:
- reset_control_assert(res->ahb_reset);
-err_rst_ahb:
- reset_control_assert(res->pwr_reset);
-err_rst_pwr:
- reset_control_assert(res->axi_s_reset);
-err_rst_axi_s:
- reset_control_assert(res->axi_m_sticky_reset);
-err_rst_axi_m_sticky:
- reset_control_assert(res->axi_m_reset);
-err_rst_axi_m:
- reset_control_assert(res->pipe_sticky_reset);
-err_rst_pipe_sticky:
- reset_control_assert(res->pipe_reset);
-err_rst_pipe:
- reset_control_assert(res->phy_reset);
-err_rst_phy:
- reset_control_assert(res->phy_ahb_reset);
- return ret;
}

static int qcom_pcie_get_resources_2_3_3(struct qcom_pcie *pcie)
@@ -1237,7 +1257,6 @@ static int qcom_pcie_init_2_7_0(struct qcom_pcie *pcie)
struct qcom_pcie_resources_2_7_0 *res = &pcie->res.v2_7_0;
struct dw_pcie *pci = pcie->pci;
struct device *dev = pci->dev;
- u32 val;
int ret;

ret = regulator_bulk_enable(ARRAY_SIZE(res->supplies), res->supplies);
@@ -1271,6 +1290,28 @@ static int qcom_pcie_init_2_7_0(struct qcom_pcie *pcie)
/* Wait for reset to complete, required on SM8450 */
usleep_range(1000, 1500);

+ return 0;
+err_disable_clocks:
+ clk_bulk_disable_unprepare(res->num_clks, res->clks);
+err_disable_regulators:
+ regulator_bulk_disable(ARRAY_SIZE(res->supplies), res->supplies);
+
+ return ret;
+}
+
+static void qcom_pcie_deinit_2_7_0(struct qcom_pcie *pcie)
+{
+ struct qcom_pcie_resources_2_7_0 *res = &pcie->res.v2_7_0;
+
+ clk_bulk_disable_unprepare(res->num_clks, res->clks);
+ regulator_bulk_disable(ARRAY_SIZE(res->supplies), res->supplies);
+}
+
+static int qcom_pcie_post_init_2_7_0(struct qcom_pcie *pcie)
+{
+ struct qcom_pcie_resources_2_7_0 *res = &pcie->res.v2_7_0;
+ u32 val;
+
/* configure PCIe to RC mode */
writel(DEVICE_TYPE_RC, pcie->parf + PCIE20_PARF_DEVICE_TYPE);

@@ -1297,27 +1338,6 @@ static int qcom_pcie_init_2_7_0(struct qcom_pcie *pcie)
writel(val, pcie->parf + PCIE20_PARF_AXI_MSTR_WR_ADDR_HALT);
}

- return 0;
-err_disable_clocks:
- clk_bulk_disable_unprepare(res->num_clks, res->clks);
-err_disable_regulators:
- regulator_bulk_disable(ARRAY_SIZE(res->supplies), res->supplies);
-
- return ret;
-}
-
-static void qcom_pcie_deinit_2_7_0(struct qcom_pcie *pcie)
-{
- struct qcom_pcie_resources_2_7_0 *res = &pcie->res.v2_7_0;
-
- clk_bulk_disable_unprepare(res->num_clks, res->clks);
- regulator_bulk_disable(ARRAY_SIZE(res->supplies), res->supplies);
-}
-
-static int qcom_pcie_post_init_2_7_0(struct qcom_pcie *pcie)
-{
- struct qcom_pcie_resources_2_7_0 *res = &pcie->res.v2_7_0;
-
/* Set pipe clock as clock source for pcie_pipe_clk_src */
if (pcie->cfg->pipe_clk_need_muxing)
clk_set_parent(res->pipe_clk_src, res->phy_pipe_clk);
@@ -1569,6 +1589,7 @@ static const struct dw_pcie_host_ops qcom_pcie_dw_ops = {
static const struct qcom_pcie_ops ops_2_1_0 = {
.get_resources = qcom_pcie_get_resources_2_1_0,
.init = qcom_pcie_init_2_1_0,
+ .post_init = qcom_pcie_post_init_2_1_0,
.deinit = qcom_pcie_deinit_2_1_0,
.ltssm_enable = qcom_pcie_2_1_0_ltssm_enable,
};
@@ -1577,6 +1598,7 @@ static const struct qcom_pcie_ops ops_2_1_0 = {
static const struct qcom_pcie_ops ops_1_0_0 = {
.get_resources = qcom_pcie_get_resources_1_0_0,
.init = qcom_pcie_init_1_0_0,
+ .post_init = qcom_pcie_post_init_1_0_0,
.deinit = qcom_pcie_deinit_1_0_0,
.ltssm_enable = qcom_pcie_2_1_0_ltssm_enable,
};
@@ -1595,6 +1617,7 @@ static const struct qcom_pcie_ops ops_2_3_2 = {
static const struct qcom_pcie_ops ops_2_4_0 = {
.get_resources = qcom_pcie_get_resources_2_4_0,
.init = qcom_pcie_init_2_4_0,
+ .post_init = qcom_pcie_post_init_2_4_0,
.deinit = qcom_pcie_deinit_2_4_0,
.ltssm_enable = qcom_pcie_2_3_2_ltssm_enable,
};
--
2.36.1