PCI: qcom: Add IPQ60xx support

IPQ60xx series of SoCs have one port of PCIe gen 3. Add support for that
platform.

The code is based on downstream[1] Codeaurora kernel v5.4 (branch
win.linuxopenwrt.2.0).

Split out the DBI registers access part from .init into .post_init. DBI
registers are only accessible after phy_power_on().

[1] https://source.codeaurora.org/quic/qsdk/oss/kernel/linux-ipq-5.4/

Link: https://lore.kernel.org/r/f7f848653c99abbf9a0f877949a44e52329543ae.1655799816.git.baruch@tkos.co.il
Tested-by: Robert Marko <robert.marko@sartura.hr>
Signed-off-by: Selvam Sathappan Periakaruppan <quic_speriaka@quicinc.com>
Signed-off-by: Baruch Siach <baruch.siach@siklu.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Johan Hovold <johan+linaro@kernel.org>
Acked-by: Stanimir Varbanov <svarbanov@mm-sol.com>

diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index ea87809..279c377 100644 (file)
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -76,6 +76,7 @@
 
 #define GEN3_RELATED_OFF                       0x890
 #define GEN3_RELATED_OFF_GEN3_ZRXDC_NONCOMPL   BIT(0)
+#define GEN3_RELATED_OFF_RXEQ_RGRDLESS_RXTS    BIT(13)
 #define GEN3_RELATED_OFF_GEN3_EQ_DISABLE       BIT(16)
 #define GEN3_RELATED_OFF_RATE_SHADOW_SEL_SHIFT 24
 #define GEN3_RELATED_OFF_RATE_SHADOW_SEL_MASK  GENMASK(25, 24)

diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
index 07f5603..4530145 100644 (file)
--- a/drivers/pci/controller/dwc/pcie-qcom.c
+++ b/drivers/pci/controller/dwc/pcie-qcom.c
@@ -52,6 +52,10 @@
 #define PCIE20_PARF_DBI_BASE_ADDR              0x168
 #define PCIE20_PARF_SLV_ADDR_SPACE_SIZE                0x16C
 #define PCIE20_PARF_MHI_CLOCK_RESET_CTRL       0x174
+#define AHB_CLK_EN                             BIT(0)
+#define MSTR_AXI_CLK_EN                                BIT(1)
+#define BYPASS                                 BIT(4)
+
 #define PCIE20_PARF_AXI_MSTR_WR_ADDR_HALT      0x178
 #define PCIE20_PARF_AXI_MSTR_WR_ADDR_HALT_V2   0x1A8
 #define PCIE20_PARF_LTSSM                      0x1B0
@@ -179,6 +183,11 @@ struct qcom_pcie_resources_2_7_0 {
        struct reset_control *pci_reset;
 };
 
+struct qcom_pcie_resources_2_9_0 {
+       struct clk_bulk_data clks[5];
+       struct reset_control *rst;
+};
+
 union qcom_pcie_resources {
        struct qcom_pcie_resources_1_0_0 v1_0_0;
        struct qcom_pcie_resources_2_1_0 v2_1_0;
@@ -186,6 +195,7 @@ union qcom_pcie_resources {
        struct qcom_pcie_resources_2_3_3 v2_3_3;
        struct qcom_pcie_resources_2_4_0 v2_4_0;
        struct qcom_pcie_resources_2_7_0 v2_7_0;
+       struct qcom_pcie_resources_2_9_0 v2_9_0;
 };
 
 struct qcom_pcie;
@@ -1279,6 +1289,112 @@ static void qcom_pcie_deinit_2_7_0(struct qcom_pcie *pcie)
        regulator_bulk_disable(ARRAY_SIZE(res->supplies), res->supplies);
 }
 
+static int qcom_pcie_get_resources_2_9_0(struct qcom_pcie *pcie)
+{
+       struct qcom_pcie_resources_2_9_0 *res = &pcie->res.v2_9_0;
+       struct dw_pcie *pci = pcie->pci;
+       struct device *dev = pci->dev;
+       int ret;
+
+       res->clks[0].id = "iface";
+       res->clks[1].id = "axi_m";
+       res->clks[2].id = "axi_s";
+       res->clks[3].id = "axi_bridge";
+       res->clks[4].id = "rchng";
+
+       ret = devm_clk_bulk_get(dev, ARRAY_SIZE(res->clks), res->clks);
+       if (ret < 0)
+               return ret;
+
+       res->rst = devm_reset_control_array_get_exclusive(dev);
+       if (IS_ERR(res->rst))
+               return PTR_ERR(res->rst);
+
+       return 0;
+}
+
+static void qcom_pcie_deinit_2_9_0(struct qcom_pcie *pcie)
+{
+       struct qcom_pcie_resources_2_9_0 *res = &pcie->res.v2_9_0;
+
+       clk_bulk_disable_unprepare(ARRAY_SIZE(res->clks), res->clks);
+}
+
+static int qcom_pcie_init_2_9_0(struct qcom_pcie *pcie)
+{
+       struct qcom_pcie_resources_2_9_0 *res = &pcie->res.v2_9_0;
+       struct device *dev = pcie->pci->dev;
+       int ret;
+
+       ret = reset_control_assert(res->rst);
+       if (ret) {
+               dev_err(dev, "reset assert failed (%d)\n", ret);
+               return ret;
+       }
+
+       /*
+        * Delay periods before and after reset deassert are working values
+        * from downstream Codeaurora kernel
+        */
+       usleep_range(2000, 2500);
+
+       ret = reset_control_deassert(res->rst);
+       if (ret) {
+               dev_err(dev, "reset deassert failed (%d)\n", ret);
+               return ret;
+       }
+
+       usleep_range(2000, 2500);
+
+       return clk_bulk_prepare_enable(ARRAY_SIZE(res->clks), res->clks);
+}
+
+static int qcom_pcie_post_init_2_9_0(struct qcom_pcie *pcie)
+{
+       struct dw_pcie *pci = pcie->pci;
+       u16 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
+       u32 val;
+       int i;
+
+       writel(SLV_ADDR_SPACE_SZ,
+               pcie->parf + PCIE20_v3_PARF_SLV_ADDR_SPACE_SIZE);
+
+       val = readl(pcie->parf + PCIE20_PARF_PHY_CTRL);
+       val &= ~BIT(0);
+       writel(val, pcie->parf + PCIE20_PARF_PHY_CTRL);
+
+       writel(0, pcie->parf + PCIE20_PARF_DBI_BASE_ADDR);
+
+       writel(DEVICE_TYPE_RC, pcie->parf + PCIE20_PARF_DEVICE_TYPE);
+       writel(BYPASS | MSTR_AXI_CLK_EN | AHB_CLK_EN,
+               pcie->parf + PCIE20_PARF_MHI_CLOCK_RESET_CTRL);
+       writel(GEN3_RELATED_OFF_RXEQ_RGRDLESS_RXTS |
+               GEN3_RELATED_OFF_GEN3_ZRXDC_NONCOMPL,
+               pci->dbi_base + GEN3_RELATED_OFF);
+
+       writel(MST_WAKEUP_EN | SLV_WAKEUP_EN | MSTR_ACLK_CGC_DIS |
+               SLV_ACLK_CGC_DIS | CORE_CLK_CGC_DIS |
+               AUX_PWR_DET | L23_CLK_RMV_DIS | L1_CLK_RMV_DIS,
+               pcie->parf + PCIE20_PARF_SYS_CTRL);
+
+       writel(0, pcie->parf + PCIE20_PARF_Q2A_FLUSH);
+
+       dw_pcie_dbi_ro_wr_en(pci);
+       writel(PCIE_CAP_SLOT_VAL, pci->dbi_base + offset + PCI_EXP_SLTCAP);
+
+       val = readl(pci->dbi_base + offset + PCI_EXP_LNKCAP);
+       val &= ~PCI_EXP_LNKCAP_ASPMS;
+       writel(val, pci->dbi_base + offset + PCI_EXP_LNKCAP);
+
+       writel(PCI_EXP_DEVCTL2_COMP_TMOUT_DIS, pci->dbi_base + offset +
+                       PCI_EXP_DEVCTL2);
+
+       for (i = 0; i < 256; i++)
+               writel(0, pcie->parf + PCIE20_PARF_BDF_TO_SID_TABLE_N + (4 * i));
+
+       return 0;
+}
+
 static int qcom_pcie_link_up(struct dw_pcie *pci)
 {
        u16 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
@@ -1468,6 +1584,15 @@ static const struct qcom_pcie_ops ops_1_9_0 = {
        .config_sid = qcom_pcie_config_sid_sm8250,
 };
 
+/* Qcom IP rev.: 2.9.0  Synopsys IP rev.: 5.00a */
+static const struct qcom_pcie_ops ops_2_9_0 = {
+       .get_resources = qcom_pcie_get_resources_2_9_0,
+       .init = qcom_pcie_init_2_9_0,
+       .post_init = qcom_pcie_post_init_2_9_0,
+       .deinit = qcom_pcie_deinit_2_9_0,
+       .ltssm_enable = qcom_pcie_2_3_2_ltssm_enable,
+};
+
 static const struct qcom_pcie_cfg apq8084_cfg = {
        .ops = &ops_1_0_0,
 };
@@ -1529,6 +1654,10 @@ static const struct qcom_pcie_cfg sc8180x_cfg = {
        .has_tbu_clk = true,
 };
 
+static const struct qcom_pcie_cfg ipq6018_cfg = {
+       .ops = &ops_2_9_0,
+};
+
 static const struct dw_pcie_ops dw_pcie_ops = {
        .link_up = qcom_pcie_link_up,
        .start_link = qcom_pcie_start_link,
@@ -1639,6 +1768,7 @@ static const struct of_device_id qcom_pcie_match[] = {
        { .compatible = "qcom,pcie-sm8450-pcie0", .data = &sm8450_pcie0_cfg },
        { .compatible = "qcom,pcie-sm8450-pcie1", .data = &sm8450_pcie1_cfg },
        { .compatible = "qcom,pcie-sc7280", .data = &sc7280_cfg },
+       { .compatible = "qcom,pcie-ipq6018", .data = &ipq6018_cfg },
        { }
 };