[PATCH v4 4/4] PCI: mediatek-gen3: Add Airoha EN7581 support

Lorenzo Bianconi
2024-07-03T16:13:27Z

Introduce support for Airoha EN7581 PCIe controller to mediatek-gen3
PCIe controller driver.

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Tested-by: Zhengping Zhang <zhengping.zhang@airoha.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
---
drivers/pci/controller/Kconfig | 2 +-
drivers/pci/controller/pcie-mediatek-gen3.c | 113 +++++++++++++++++++-
2 files changed, 113 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/controller/Kconfig b/drivers/pci/controller/Kconfig
index e534c02ee34f..3bd6c9430010 100644
--- a/drivers/pci/controller/Kconfig
+++ b/drivers/pci/controller/Kconfig
@@ -196,7 +196,7 @@ config PCIE_MEDIATEK

config PCIE_MEDIATEK_GEN3
tristate "MediaTek Gen3 PCIe controller"
- depends on ARCH_MEDIATEK || COMPILE_TEST
+ depends on ARCH_AIROHA || ARCH_MEDIATEK || COMPILE_TEST
depends on PCI_MSI
help
Adds support for PCIe Gen3 MAC controller for MediaTek SoCs.
diff --git a/drivers/pci/controller/pcie-mediatek-gen3.c b/drivers/pci/controller/pcie-mediatek-gen3.c
index 438a5222d986..e064f467ced6 100644
--- a/drivers/pci/controller/pcie-mediatek-gen3.c
+++ b/drivers/pci/controller/pcie-mediatek-gen3.c
@@ -6,7 +6,9 @@
* Author: Jianjun Wang <jianjun.wang@mediatek.com>
*/

+#include <linux/bitfield.h>
#include <linux/clk.h>
+#include <linux/clk-provider.h>
#include <linux/delay.h>
#include <linux/iopoll.h>
#include <linux/irq.h>
@@ -15,6 +17,8 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/msi.h>
+#include <linux/of_device.h>
+#include <linux/of_pci.h>
#include <linux/pci.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
@@ -29,6 +33,12 @@
#define PCI_CLASS(class) (class << 8)
#define PCIE_RC_MODE BIT(0)

+#define PCIE_EQ_PRESET_01_REG 0x100
+#define PCIE_VAL_LN0_DOWNSTREAM GENMASK(6, 0)
+#define PCIE_VAL_LN0_UPSTREAM GENMASK(14, 8)
+#define PCIE_VAL_LN1_DOWNSTREAM GENMASK(22, 16)
+#define PCIE_VAL_LN1_UPSTREAM GENMASK(30, 24)
+
#define PCIE_CFGNUM_REG 0x140
#define PCIE_CFG_DEVFN(devfn) ((devfn) & GENMASK(7, 0))
#define PCIE_CFG_BUS(bus) (((bus) << 8) & GENMASK(15, 8))
@@ -68,6 +78,14 @@
#define PCIE_MSI_SET_ENABLE_REG 0x190
#define PCIE_MSI_SET_ENABLE GENMASK(PCIE_MSI_SET_NUM - 1, 0)

+#define PCIE_PIPE4_PIE8_REG 0x338
+#define PCIE_K_FINETUNE_MAX GENMASK(5, 0)
+#define PCIE_K_FINETUNE_ERR GENMASK(7, 6)
+#define PCIE_K_PRESET_TO_USE GENMASK(18, 8)
+#define PCIE_K_PHYPARAM_QUERY BIT(19)
+#define PCIE_K_QUERY_TIMEOUT BIT(20)
+#define PCIE_K_PRESET_TO_USE_16G GENMASK(31, 21)
+
#define PCIE_MSI_SET_BASE_REG 0xc00
#define PCIE_MSI_SET_OFFSET 0x10
#define PCIE_MSI_SET_STATUS_OFFSET 0x04
@@ -100,7 +118,10 @@
#define PCIE_ATR_TLP_TYPE_MEM PCIE_ATR_TLP_TYPE(0)
#define PCIE_ATR_TLP_TYPE_IO PCIE_ATR_TLP_TYPE(2)

-#define MAX_NUM_PHY_RESETS 1
+#define MAX_NUM_PHY_RESETS 3
+
+/* Time in ms needed to complete PCIe reset on EN7581 SoC */
+#define PCIE_EN7581_RESET_TIME_MS 100

struct mtk_gen3_pcie;

@@ -847,6 +868,85 @@ static int mtk_pcie_parse_port(struct mtk_gen3_pcie *pcie)
return 0;
}

+static int mtk_pcie_en7581_power_up(struct mtk_gen3_pcie *pcie)
+{
+ struct device *dev = pcie->dev;
+ int err;
+ u32 val;
+
+ /*
+ * Wait for the time needed to complete the bulk assert in
+ * mtk_pcie_setup for EN7581 SoC.
+ */
+ mdelay(PCIE_EN7581_RESET_TIME_MS);
+
+ err = phy_init(pcie->phy);
+ if (err) {
+ dev_err(dev, "failed to initialize PHY\n");
+ return err;
+ }
+
+ err = phy_power_on(pcie->phy);
+ if (err) {
+ dev_err(dev, "failed to power on PHY\n");
+ goto err_phy_on;
+ }
+
+ err = reset_control_bulk_deassert(pcie->soc->phy_resets.num_resets, pcie->phy_resets);
+ if (err) {
+ dev_err(dev, "failed to deassert PHYs\n");
+ goto err_phy_deassert;
+ }
+
+ /*
+ * Wait for the time needed to complete the bulk de-assert above.
+ * This time is specific for EN7581 SoC.
+ */
+ mdelay(PCIE_EN7581_RESET_TIME_MS);
+
+ pm_runtime_enable(dev);
+ pm_runtime_get_sync(dev);
+
+ err = clk_bulk_prepare(pcie->num_clks, pcie->clks);
+ if (err) {
+ dev_err(dev, "failed to prepare clock\n");
+ goto err_clk_prepare;
+ }
+
+ val = FIELD_PREP(PCIE_VAL_LN0_DOWNSTREAM, 0x47) |
+ FIELD_PREP(PCIE_VAL_LN1_DOWNSTREAM, 0x47) |
+ FIELD_PREP(PCIE_VAL_LN0_UPSTREAM, 0x41) |
+ FIELD_PREP(PCIE_VAL_LN1_UPSTREAM, 0x41);
+ writel_relaxed(val, pcie->base + PCIE_EQ_PRESET_01_REG);
+
+ val = PCIE_K_PHYPARAM_QUERY | PCIE_K_QUERY_TIMEOUT |
+ FIELD_PREP(PCIE_K_PRESET_TO_USE_16G, 0x80) |
+ FIELD_PREP(PCIE_K_PRESET_TO_USE, 0x2) |
+ FIELD_PREP(PCIE_K_FINETUNE_MAX, 0xf);
+ writel_relaxed(val, pcie->base + PCIE_PIPE4_PIE8_REG);
+
+ err = clk_bulk_enable(pcie->num_clks, pcie->clks);
+ if (err) {
+ dev_err(dev, "failed to prepare clock\n");
+ goto err_clk_enable;
+ }
+
+ return 0;
+
+err_clk_enable:
+ clk_bulk_unprepare(pcie->num_clks, pcie->clks);
+err_clk_prepare:
+ pm_runtime_put_sync(dev);
+ pm_runtime_disable(dev);
+ reset_control_bulk_assert(pcie->soc->phy_resets.num_resets, pcie->phy_resets);
+err_phy_deassert:
+ phy_power_off(pcie->phy);
+err_phy_on:
+ phy_exit(pcie->phy);
+
+ return err;
+}
+
static int mtk_pcie_power_up(struct mtk_gen3_pcie *pcie)
{
struct device *dev = pcie->dev;
@@ -1113,7 +1213,18 @@ static const struct mtk_gen3_pcie_pdata mtk_pcie_soc_mt8192 = {
},
};

+static const struct mtk_gen3_pcie_pdata mtk_pcie_soc_en7581 = {
+ .power_up = mtk_pcie_en7581_power_up,
+ .phy_resets = {
+ .id[0] = "phy-lane0",
+ .id[1] = "phy-lane1",
+ .id[2] = "phy-lane2",
+ .num_resets = 3,
+ },
+};
+
static const struct of_device_id mtk_pcie_of_match[] = {
+ { .compatible = "airoha,en7581-pcie", .data = &mtk_pcie_soc_en7581 },
{ .compatible = "mediatek,mt8192-pcie", .data = &mtk_pcie_soc_mt8192 },
{},
};
--
2.45.2