Hi Bjorn, Thanks for your review comments. On Mon, Jan 24 2022, Bjorn Helgaas wrote: > Capitalize subject line to match history, i.e., > > $ git log --oneline drivers/pci/controller/dwc/pcie-qcom.c > 3f13d611aa6b PCI: qcom: Use __be16 type to store return value from cpu_to_be16() > 4e0e90539bb0 PCI: qcom: Fix an error handling path in 'qcom_pcie_probe()' > 45a3ec891370 PCI: qcom: Add sc8180x compatible > aa9c0df98c29 PCI: qcom: Switch pcie_1_pipe_clk_src after PHY init in SC7280 > b89ff410253d PCI: qcom: Replace ops with struct pcie_cfg in pcie match data > 2cfef1971aea PCI: qcom: Use PHY_REFCLK_USE_PAD only for ipq8064 > 7081556f81f7 PCI: qcom: Add support for ddrss_sf_tbu clock > 4c9398822106 PCI: qcom: Add support for configuring BDF to SID mapping for SM8250 > e1dd639e374a PCI: qcom: Add SM8250 SoC support > > A good one would be: > > PCI: qcom: Add IPQ60xx support > > We already know this is a PCIe controller, and it's nice to have the > important words like "IPQ60xx" early in the message so they don't get > truncated or wrapped. > > On Mon, Jan 24, 2022 at 06:27:31PM +0200, Baruch Siach wrote: >> From: Selvam Sathappan Periakaruppan <speriaka@xxxxxxxxxxxxxx> >> >> 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/ >> >> Signed-off-by: Selvam Sathappan Periakaruppan <speriaka@xxxxxxxxxxxxxx> >> Signed-off-by: Baruch Siach <baruch.siach@xxxxxxxxx> >> --- >> v5: >> >> * Remove comments from qcom_pcie_init_2_9_0() (Bjorn Andersson) >> >> v4: >> >> * Rebase on v5.16-rc1 >> >> v3: >> * Drop speed setup; rely on generic code (Rob Herring) >> >> * Drop unused CLK_RATE macros (Bjorn Helgaas) >> >> * Minor formatting fixes (Bjorn Helgaas) >> >> * Add reference to downstream Codeaurora kernel tree (Bjorn Helgaas) >> >> v2: >> * Drop ATU configuration; rely on common code instead >> >> * Use more common register macros >> >> * Use bulk clk and reset APIs >> --- >> drivers/pci/controller/dwc/pcie-designware.h | 1 + >> drivers/pci/controller/dwc/pcie-qcom.c | 137 +++++++++++++++++++ >> 2 files changed, 138 insertions(+) >> >> diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h >> index ea87809ee298..279c3778a13b 100644 >> --- 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 c19cd506ed3f..5d47e572da44 100644 >> --- 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 >> @@ -171,6 +175,11 @@ struct qcom_pcie_resources_2_7_0 { >> struct clk *ref_clk_src; >> }; >> >> +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; >> @@ -178,6 +187,7 @@ 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; >> @@ -1297,6 +1307,119 @@ static void qcom_pcie_post_deinit_2_7_0(struct qcom_pcie *pcie) >> clk_disable_unprepare(res->pipe_clk); >> } >> >> +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; >> + } >> + >> + usleep_range(2000, 2500); > > Where do these sleep durations come from? If they're specified > somewhere by PCIe, can you include a citation, e.g., a section number > in the spec. As I mentioned before, I have no access to hardware documentation. I'm only porting working code from downstream kernel. In a comment on v4 Bjorn Andersson mentioned "datasheet stating the minimum timing of the operations to be performed to get the PCIe controller into a known (clean) state". https://lore.kernel.org/all/Ydd5Wh0KeADBQ%2Fh1@ripper/ I have no further details. >> + ret = reset_control_deassert(res->rst); >> + if (ret) { >> + dev_err(dev, "reset deassert failed (%d)\n", ret); >> + return ret; >> + } >> + >> + usleep_range(2000, 2500); >> + >> + ret = clk_bulk_prepare_enable(ARRAY_SIZE(res->clks), res->clks); >> + if (ret) >> + goto err_reset; >> + >> + return 0; >> + >> +err_reset: >> + reset_control_assert(res->rst); >> + >> + return ret; >> +} >> + >> +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_LINK1_VAL, pci->dbi_base + offset + PCI_EXP_SLTCAP); > > Is "PCIE_CAP_LINK1_VAL" misnamed? If it's being written to > PCI_EXP_SLTCAP, seems like it should be named something about a > *slot*, not a *link*. > > Or is this an error and it should this be written to PCI_EXP_LNKCAP > instead? As above, I don't know. I can only mention that the exact same assignment is currently also in qcom_pcie_init_2_3_3(). > Could PCIE_CAP_LINK1_VAL be defined in terms of PCI_EXP_SLTCAP_* or > PCI_EXP_LNKCAP_*? It surely can. Whether it makes sense I can't tell. >> + /* Configure PCIe link capabilities for ASPM */ >> + val = readl(pci->dbi_base + offset + PCI_EXP_LNKCAP); >> + val &= ~PCI_EXP_LNKCAP_ASPMS; >> + writel(val, pci->dbi_base + offset + PCI_EXP_LNKCAP); > > Thanks for using the standard PCI_EXP_LNKCAP and similar #defines. > Does this mean you don't advertise any ASPM support on this platform? > If so, that's fine, but the comment could be more specific. > "Configure" doesn't give any hint about *how* they are configured. Again, the same code is in qcom_pcie_init_2_3_3(). I'll just drop the comment in the next submission. Thanks, baruch >> + writel(PCI_EXP_DEVCTL2_COMP_TMOUT_DIS, pci->dbi_base + offset + >> + PCI_EXP_DEVCTL2); >> + >> + for (i = 0; i < 256; i++) >> + writel(0x0, 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); >> @@ -1487,6 +1610,15 @@ 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, >> }; >> @@ -1520,6 +1652,10 @@ static const struct qcom_pcie_cfg sc7280_cfg = { >> .pipe_clk_need_muxing = 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, >> @@ -1629,6 +1765,7 @@ static const struct of_device_id qcom_pcie_match[] = { >> { .compatible = "qcom,pcie-sm8250", .data = &sm8250_cfg }, >> { .compatible = "qcom,pcie-sc8180x", .data = &sm8250_cfg }, >> { .compatible = "qcom,pcie-sc7280", .data = &sc7280_cfg }, >> + { .compatible = "qcom,pcie-ipq6018", .data = &ipq6018_cfg }, >> { } >> }; >> >> -- >> 2.34.1 -- ~. .~ Tk Open Systems =}------------------------------------------------ooO--U--Ooo------------{= - baruch@xxxxxxxxxx - tel: +972.52.368.4656, http://www.tkos.co.il -
