2024-02-27 11:12:35

by Minda Chen

[permalink] [raw]
Subject: [PATCH v15,RESEND 21/23] PCI: starfive: Add JH7110 PCIe controller

Add StarFive JH7110 SoC PCIe controller platform driver codes, JH7110
with PLDA host PCIe core.

Signed-off-by: Minda Chen <[email protected]>
Co-developed-by: Kevin Xie <[email protected]>
Reviewed-by: Mason Huo <[email protected]>
---
MAINTAINERS | 7 +
drivers/pci/controller/plda/Kconfig | 12 +
drivers/pci/controller/plda/Makefile | 1 +
drivers/pci/controller/plda/pcie-plda.h | 71 ++-
drivers/pci/controller/plda/pcie-starfive.c | 473 ++++++++++++++++++++
5 files changed, 563 insertions(+), 1 deletion(-)
create mode 100644 drivers/pci/controller/plda/pcie-starfive.c

diff --git a/MAINTAINERS b/MAINTAINERS
index fc9576e69a71..d3b0a0fb754f 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -17078,6 +17078,13 @@ S: Maintained
F: Documentation/devicetree/bindings/pci/socionext,uniphier-pcie*
F: drivers/pci/controller/dwc/pcie-uniphier*

+PCIE DRIVER FOR STARFIVE JH71x0
+M: Kevin Xie <[email protected]>
+L: [email protected]
+S: Maintained
+F: Documentation/devicetree/bindings/pci/starfive*
+F: drivers/pci/controller/plda/pcie-starfive.c
+
PCIE DRIVER FOR ST SPEAR13XX
M: Pratyush Anand <[email protected]>
L: [email protected]
diff --git a/drivers/pci/controller/plda/Kconfig b/drivers/pci/controller/plda/Kconfig
index e54a82ee94f5..c0e14146d7e4 100644
--- a/drivers/pci/controller/plda/Kconfig
+++ b/drivers/pci/controller/plda/Kconfig
@@ -15,4 +15,16 @@ config PCIE_MICROCHIP_HOST
Say Y here if you want kernel to support the Microchip AXI PCIe
Host Bridge driver.

+config PCIE_STARFIVE_HOST
+ tristate "StarFive PCIe host controller"
+ depends on PCI_MSI && OF
+ depends on ARCH_STARFIVE || COMPILE_TEST
+ select PCIE_PLDA_HOST
+ help
+ Say Y here if you want to support the StarFive PCIe controller in
+ host mode. StarFive PCIe controller uses PLDA PCIe core.
+
+ If you choose to build this driver as module it will be dynamically
+ linked and module will be called pcie-starfive.ko.
+
endmenu
diff --git a/drivers/pci/controller/plda/Makefile b/drivers/pci/controller/plda/Makefile
index 4340ab007f44..0ac6851bed48 100644
--- a/drivers/pci/controller/plda/Makefile
+++ b/drivers/pci/controller/plda/Makefile
@@ -1,3 +1,4 @@
# SPDX-License-Identifier: GPL-2.0
obj-$(CONFIG_PCIE_PLDA_HOST) += pcie-plda-host.o
obj-$(CONFIG_PCIE_MICROCHIP_HOST) += pcie-microchip-host.o
+obj-$(CONFIG_PCIE_STARFIVE_HOST) += pcie-starfive.o
diff --git a/drivers/pci/controller/plda/pcie-plda.h b/drivers/pci/controller/plda/pcie-plda.h
index 7b69891700a4..04e385758a2f 100644
--- a/drivers/pci/controller/plda/pcie-plda.h
+++ b/drivers/pci/controller/plda/pcie-plda.h
@@ -10,10 +10,20 @@
#define PLDA_MAX_NUM_MSI_IRQS 32

/* PCIe Bridge Phy Regs */
+#define GEN_SETTINGS 0x80
+#define RP_ENABLE 1
+#define PCIE_PCI_IDS_DW1 0x9c
+#define IDS_CLASS_CODE_SHIFT 16
+#define REVISION_ID_MASK GENMASK(7, 0)
+#define CLASS_CODE_ID_MASK GENMASK(31, 8)
#define PCIE_PCI_IRQ_DW0 0xa8
#define MSIX_CAP_MASK BIT(31)
#define NUM_MSI_MSGS_MASK GENMASK(6, 4)
#define NUM_MSI_MSGS_SHIFT 4
+#define PCI_MISC 0xb4
+#define PHY_FUNCTION_DIS BIT(15)
+#define PCIE_WINROM 0xfc
+#define PREF_MEM_WIN_64_SUPPORT BIT(3)

#define IMASK_LOCAL 0x180
#define DMA_END_ENGINE_0_MASK 0x00000000u
@@ -65,6 +75,8 @@
#define ISTATUS_HOST 0x18c
#define IMSI_ADDR 0x190
#define ISTATUS_MSI 0x194
+#define PMSG_SUPPORT_RX 0x3f0
+#define PMSG_LTR_SUPPORT BIT(2)

/* PCIe Master table init defines */
#define ATR0_PCIE_WIN0_SRCADDR_PARAM 0x600u
@@ -86,6 +98,8 @@
#define PCIE_TX_RX_INTERFACE 0x00000000u
#define PCIE_CONFIG_INTERFACE 0x00000001u

+#define CONFIG_SPACE_ADDR_OFFSET 0x1000u
+
#define ATR_ENTRY_SIZE 32

enum plda_int_event {
@@ -200,4 +214,59 @@ static inline void plda_set_default_msi(struct plda_msi *msi)
msi->vector_phy = IMSI_ADDR;
msi->num_vectors = PLDA_MAX_NUM_MSI_IRQS;
}
-#endif
+
+static inline void plda_pcie_enable_root_port(struct plda_pcie_rp *plda)
+{
+ u32 value;
+
+ value = readl_relaxed(plda->bridge_addr + GEN_SETTINGS);
+ value |= RP_ENABLE;
+ writel_relaxed(value, plda->bridge_addr + GEN_SETTINGS);
+}
+
+static inline void plda_pcie_set_standard_class(struct plda_pcie_rp *plda)
+{
+ u32 value;
+
+ /* set class code and reserve revision id */
+ value = readl_relaxed(plda->bridge_addr + PCIE_PCI_IDS_DW1);
+ value &= REVISION_ID_MASK;
+ value |= (PCI_CLASS_BRIDGE_PCI << IDS_CLASS_CODE_SHIFT);
+ writel_relaxed(value, plda->bridge_addr + PCIE_PCI_IDS_DW1);
+}
+
+static inline void plda_pcie_set_pref_win_64bit(struct plda_pcie_rp *plda)
+{
+ u32 value;
+
+ value = readl_relaxed(plda->bridge_addr + PCIE_WINROM);
+ value |= PREF_MEM_WIN_64_SUPPORT;
+ writel_relaxed(value, plda->bridge_addr + PCIE_WINROM);
+}
+
+static inline void plda_pcie_disable_ltr(struct plda_pcie_rp *plda)
+{
+ u32 value;
+
+ value = readl_relaxed(plda->bridge_addr + PMSG_SUPPORT_RX);
+ value &= ~PMSG_LTR_SUPPORT;
+ writel_relaxed(value, plda->bridge_addr + PMSG_SUPPORT_RX);
+}
+
+static inline void plda_pcie_disable_func(struct plda_pcie_rp *plda)
+{
+ u32 value;
+
+ value = readl_relaxed(plda->bridge_addr + PCI_MISC);
+ value |= PHY_FUNCTION_DIS;
+ writel_relaxed(value, plda->bridge_addr + PCI_MISC);
+}
+
+static inline void plda_pcie_write_rc_bar(struct plda_pcie_rp *plda, u64 val)
+{
+ void __iomem *addr = plda->bridge_addr + CONFIG_SPACE_ADDR_OFFSET;
+
+ writel_relaxed(lower_32_bits(val), addr + PCI_BASE_ADDRESS_0);
+ writel_relaxed(upper_32_bits(val), addr + PCI_BASE_ADDRESS_1);
+}
+#endif /* _PCIE_PLDA_H */
diff --git a/drivers/pci/controller/plda/pcie-starfive.c b/drivers/pci/controller/plda/pcie-starfive.c
new file mode 100644
index 000000000000..9bb9f0e29565
--- /dev/null
+++ b/drivers/pci/controller/plda/pcie-starfive.c
@@ -0,0 +1,473 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * PCIe host controller driver for StarFive JH7110 Soc.
+ *
+ * Copyright (C) 2023 StarFive Technology Co., Ltd.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_pci.h>
+#include <linux/pci.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+#include "../../pci.h"
+
+#include "pcie-plda.h"
+
+#define PCIE_FUNC_NUM 4
+
+/* system control */
+#define STG_SYSCON_PCIE0_BASE 0x48
+#define STG_SYSCON_PCIE1_BASE 0x1f8
+
+#define STG_SYSCON_AR_OFFSET 0x78
+#define STG_SYSCON_AXI4_SLVL_AR_MASK GENMASK(22, 8)
+#define STG_SYSCON_AXI4_SLVL_PHY_AR(x) FIELD_PREP(GENMASK(20, 17), x)
+#define STG_SYSCON_AW_OFFSET 0x7c
+#define STG_SYSCON_AXI4_SLVL_AW_MASK GENMASK(14, 0)
+#define STG_SYSCON_AXI4_SLVL_PHY_AW(x) FIELD_PREP(GENMASK(12, 9), x)
+#define STG_SYSCON_CLKREQ BIT(22)
+#define STG_SYSCON_CKREF_SRC_MASK GENMASK(19, 18)
+#define STG_SYSCON_RP_NEP_OFFSET 0xe8
+#define STG_SYSCON_K_RP_NEP BIT(8)
+#define STG_SYSCON_LNKSTA_OFFSET 0x170
+#define DATA_LINK_ACTIVE BIT(5)
+
+/* Parameters for the waiting for link up routine */
+#define LINK_WAIT_MAX_RETRIES 10
+#define LINK_WAIT_USLEEP_MIN 90000
+#define LINK_WAIT_USLEEP_MAX 100000
+
+struct starfive_jh7110_pcie {
+ struct plda_pcie_rp plda;
+ struct reset_control *resets;
+ struct clk_bulk_data *clks;
+ struct regmap *reg_syscon;
+ struct gpio_desc *power_gpio;
+ struct gpio_desc *reset_gpio;
+ struct phy *phy;
+
+ unsigned int stg_pcie_base;
+ int num_clks;
+};
+
+/*
+ * The BAR0/1 of bridge should be hidden during enumeration to
+ * avoid the sizing and resource allocation by PCIe core.
+ */
+static bool starfive_pcie_hide_rc_bar(struct pci_bus *bus, unsigned int devfn,
+ int offset)
+{
+ if (pci_is_root_bus(bus) && !devfn &&
+ (offset == PCI_BASE_ADDRESS_0 || offset == PCI_BASE_ADDRESS_1))
+ return true;
+
+ return false;
+}
+
+static int starfive_pcie_config_write(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 value)
+{
+ if (starfive_pcie_hide_rc_bar(bus, devfn, where))
+ return PCIBIOS_SUCCESSFUL;
+
+ return pci_generic_config_write(bus, devfn, where, size, value);
+}
+
+static int starfive_pcie_config_read(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 *value)
+{
+ if (starfive_pcie_hide_rc_bar(bus, devfn, where)) {
+ *value = 0;
+ return PCIBIOS_SUCCESSFUL;
+ }
+
+ return pci_generic_config_read(bus, devfn, where, size, value);
+}
+
+static int starfive_pcie_parse_dt(struct starfive_jh7110_pcie *pcie,
+ struct device *dev)
+{
+ int domain_nr;
+
+ pcie->num_clks = devm_clk_bulk_get_all(dev, &pcie->clks);
+ if (pcie->num_clks < 0)
+ return dev_err_probe(dev, pcie->num_clks,
+ "failed to get pcie clocks\n");
+
+ pcie->resets = devm_reset_control_array_get_exclusive(dev);
+ if (IS_ERR(pcie->resets))
+ return dev_err_probe(dev, PTR_ERR(pcie->resets),
+ "failed to get pcie resets");
+
+ pcie->reg_syscon =
+ syscon_regmap_lookup_by_phandle(dev->of_node,
+ "starfive,stg-syscon");
+
+ if (IS_ERR(pcie->reg_syscon))
+ return dev_err_probe(dev, PTR_ERR(pcie->reg_syscon),
+ "failed to parse starfive,stg-syscon\n");
+
+ pcie->phy = devm_phy_optional_get(dev, NULL);
+ if (IS_ERR(pcie->phy))
+ return dev_err_probe(dev, PTR_ERR(pcie->phy),
+ "failed to get pcie phy\n");
+
+ domain_nr = of_get_pci_domain_nr(dev->of_node);
+
+ if (domain_nr < 0 || domain_nr > 1)
+ return dev_err_probe(dev, -ENODEV,
+ "failed to get valid pcie domain\n");
+
+ if (domain_nr == 0)
+ pcie->stg_pcie_base = STG_SYSCON_PCIE0_BASE;
+ else
+ pcie->stg_pcie_base = STG_SYSCON_PCIE1_BASE;
+
+ pcie->reset_gpio = devm_gpiod_get_optional(dev, "perst",
+ GPIOD_OUT_HIGH);
+ if (IS_ERR(pcie->reset_gpio))
+ return dev_err_probe(dev, PTR_ERR(pcie->reset_gpio),
+ "failed to get perst-gpio\n");
+
+ pcie->power_gpio = devm_gpiod_get_optional(dev, "enable",
+ GPIOD_OUT_LOW);
+ if (IS_ERR(pcie->power_gpio))
+ return dev_err_probe(dev, PTR_ERR(pcie->power_gpio),
+ "failed to get power-gpio\n");
+
+ return 0;
+}
+
+static struct pci_ops starfive_pcie_ops = {
+ .map_bus = plda_pcie_map_bus,
+ .read = starfive_pcie_config_read,
+ .write = starfive_pcie_config_write,
+};
+
+static int starfive_pcie_clk_rst_init(struct starfive_jh7110_pcie *pcie)
+{
+ struct device *dev = pcie->plda.dev;
+ int ret;
+
+ ret = clk_bulk_prepare_enable(pcie->num_clks, pcie->clks);
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to enable clocks\n");
+
+ ret = reset_control_deassert(pcie->resets);
+ if (ret) {
+ clk_bulk_disable_unprepare(pcie->num_clks, pcie->clks);
+ dev_err_probe(dev, ret, "failed to deassert resets\n");
+ }
+
+ return ret;
+}
+
+static void starfive_pcie_clk_rst_deinit(struct starfive_jh7110_pcie *pcie)
+{
+ reset_control_assert(pcie->resets);
+ clk_bulk_disable_unprepare(pcie->num_clks, pcie->clks);
+}
+
+static bool starfive_pcie_link_up(struct plda_pcie_rp *plda)
+{
+ struct starfive_jh7110_pcie *pcie =
+ container_of(plda, struct starfive_jh7110_pcie, plda);
+ int ret;
+ u32 stg_reg_val;
+
+ ret = regmap_read(pcie->reg_syscon,
+ pcie->stg_pcie_base + STG_SYSCON_LNKSTA_OFFSET,
+ &stg_reg_val);
+ if (ret) {
+ dev_err(pcie->plda.dev, "failed to read link status\n");
+ return false;
+ }
+
+ return !!(stg_reg_val & DATA_LINK_ACTIVE);
+}
+
+static int starfive_pcie_host_wait_for_link(struct starfive_jh7110_pcie *pcie)
+{
+ int retries;
+
+ /* Check if the link is up or not */
+ for (retries = 0; retries < LINK_WAIT_MAX_RETRIES; retries++) {
+ if (starfive_pcie_link_up(&pcie->plda)) {
+ dev_info(pcie->plda.dev, "port link up\n");
+ return 0;
+ }
+ usleep_range(LINK_WAIT_USLEEP_MIN, LINK_WAIT_USLEEP_MAX);
+ }
+
+ return -ETIMEDOUT;
+}
+
+static int starfive_pcie_enable_phy(struct device *dev,
+ struct starfive_jh7110_pcie *pcie)
+{
+ int ret;
+
+ if (!pcie->phy)
+ return 0;
+
+ ret = phy_init(pcie->phy);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "failed to initialize pcie phy\n");
+
+ ret = phy_set_mode(pcie->phy, PHY_MODE_PCIE);
+ if (ret) {
+ dev_err_probe(dev, ret, "failed to set pcie mode\n");
+ goto err_phy_on;
+ }
+
+ ret = phy_power_on(pcie->phy);
+ if (ret) {
+ dev_err_probe(dev, ret, "failed to power on pcie phy\n");
+ goto err_phy_on;
+ }
+
+ return 0;
+
+err_phy_on:
+ phy_exit(pcie->phy);
+ return ret;
+}
+
+static void starfive_pcie_disable_phy(struct starfive_jh7110_pcie *pcie)
+{
+ phy_power_off(pcie->phy);
+ phy_exit(pcie->phy);
+}
+
+static void starfive_pcie_host_deinit(struct plda_pcie_rp *plda)
+{
+ struct starfive_jh7110_pcie *pcie =
+ container_of(plda, struct starfive_jh7110_pcie, plda);
+
+ starfive_pcie_clk_rst_deinit(pcie);
+ if (pcie->power_gpio)
+ gpiod_set_value_cansleep(pcie->power_gpio, 0);
+ starfive_pcie_disable_phy(pcie);
+}
+
+static int starfive_pcie_host_init(struct plda_pcie_rp *plda)
+{
+ struct starfive_jh7110_pcie *pcie =
+ container_of(plda, struct starfive_jh7110_pcie, plda);
+ struct device *dev = plda->dev;
+ int ret;
+ int i;
+
+ ret = starfive_pcie_enable_phy(dev, pcie);
+ if (ret)
+ return ret;
+
+ regmap_update_bits(pcie->reg_syscon,
+ pcie->stg_pcie_base + STG_SYSCON_RP_NEP_OFFSET,
+ STG_SYSCON_K_RP_NEP, STG_SYSCON_K_RP_NEP);
+
+ regmap_update_bits(pcie->reg_syscon,
+ pcie->stg_pcie_base + STG_SYSCON_AW_OFFSET,
+ STG_SYSCON_CKREF_SRC_MASK,
+ FIELD_PREP(STG_SYSCON_CKREF_SRC_MASK, 2));
+
+ regmap_update_bits(pcie->reg_syscon,
+ pcie->stg_pcie_base + STG_SYSCON_AW_OFFSET,
+ STG_SYSCON_CLKREQ, STG_SYSCON_CLKREQ);
+
+ ret = starfive_pcie_clk_rst_init(pcie);
+ if (ret)
+ return ret;
+
+ if (pcie->power_gpio)
+ gpiod_set_value_cansleep(pcie->power_gpio, 1);
+
+ if (pcie->reset_gpio)
+ gpiod_set_value_cansleep(pcie->reset_gpio, 1);
+
+ /* Disable physical functions except #0 */
+ for (i = 1; i < PCIE_FUNC_NUM; i++) {
+ regmap_update_bits(pcie->reg_syscon,
+ pcie->stg_pcie_base + STG_SYSCON_AR_OFFSET,
+ STG_SYSCON_AXI4_SLVL_AR_MASK,
+ STG_SYSCON_AXI4_SLVL_PHY_AR(i));
+
+ regmap_update_bits(pcie->reg_syscon,
+ pcie->stg_pcie_base + STG_SYSCON_AW_OFFSET,
+ STG_SYSCON_AXI4_SLVL_AW_MASK,
+ STG_SYSCON_AXI4_SLVL_PHY_AW(i));
+
+ plda_pcie_disable_func(plda);
+ }
+
+ regmap_update_bits(pcie->reg_syscon,
+ pcie->stg_pcie_base + STG_SYSCON_AR_OFFSET,
+ STG_SYSCON_AXI4_SLVL_AR_MASK, 0);
+ regmap_update_bits(pcie->reg_syscon,
+ pcie->stg_pcie_base + STG_SYSCON_AW_OFFSET,
+ STG_SYSCON_AXI4_SLVL_AW_MASK, 0);
+
+ plda_pcie_enable_root_port(plda);
+ plda_pcie_write_rc_bar(plda, 0);
+
+ /* PCIe PCI Standard Configuration Identification Settings. */
+ plda_pcie_set_standard_class(plda);
+
+ /*
+ * The LTR message forwarding of PCIe Message Reception was set by core
+ * as default, but the forward id & addr are also need to be reset.
+ * If we do not disable LTR message forwarding here, or set a legal
+ * forwarding address, the kernel will get stuck after the driver probe.
+ * To workaround, disable the LTR message forwarding support on
+ * PCIe Message Reception.
+ */
+ plda_pcie_disable_ltr(plda);
+
+ /* Prefetchable memory window 64-bit addressing support */
+ plda_pcie_set_pref_win_64bit(plda);
+
+ /*
+ * Ensure that PERST has been asserted for at least 100 ms,
+ * the sleep value is T_PVPERL from PCIe CEM spec r2.0 (Table 2-4)
+ */
+ msleep(100);
+ if (pcie->reset_gpio)
+ gpiod_set_value_cansleep(pcie->reset_gpio, 0);
+
+ /*
+ * With a Downstream Port (<=5GT/s), software must wait a minimum
+ * of 100ms following exit from a conventional reset before
+ * sending a configuration request to the device.
+ */
+ msleep(PCIE_RESET_CONFIG_DEVICE_WAIT_MS);
+
+ if (starfive_pcie_host_wait_for_link(pcie))
+ dev_info(dev, "port link down\n");
+
+ return 0;
+}
+
+static const struct plda_pcie_host_ops sf_host_ops = {
+ .host_init = starfive_pcie_host_init,
+ .host_deinit = starfive_pcie_host_deinit,
+};
+
+static const struct plda_event stf_pcie_event = {
+ .intx_event = EVENT_PM_MSI_INT_INTX,
+ .msi_event = EVENT_PM_MSI_INT_MSI
+};
+
+static int starfive_pcie_probe(struct platform_device *pdev)
+{
+ struct starfive_jh7110_pcie *pcie;
+ struct device *dev = &pdev->dev;
+ struct plda_pcie_rp *plda;
+ int ret;
+
+ pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL);
+ if (!pcie)
+ return -ENOMEM;
+
+ plda = &pcie->plda;
+ plda->dev = dev;
+
+ ret = starfive_pcie_parse_dt(pcie, dev);
+ if (ret)
+ return ret;
+
+ plda->host_ops = &sf_host_ops;
+ plda->num_events = PLDA_MAX_EVENT_NUM;
+ /* mask doorbell event */
+ plda->events_bitmap = GENMASK(PLDA_INT_EVENT_NUM - 1, 0)
+ & ~BIT(PLDA_AXI_DOORBELL)
+ & ~BIT(PLDA_PCIE_DOORBELL);
+ plda->events_bitmap <<= PLDA_NUM_DMA_EVENTS;
+ ret = plda_pcie_host_init(&pcie->plda, &starfive_pcie_ops,
+ &stf_pcie_event);
+ if (ret)
+ return ret;
+
+ pm_runtime_enable(&pdev->dev);
+ pm_runtime_get_sync(&pdev->dev);
+ platform_set_drvdata(pdev, pcie);
+
+ return 0;
+}
+
+static void starfive_pcie_remove(struct platform_device *pdev)
+{
+ struct starfive_jh7110_pcie *pcie = platform_get_drvdata(pdev);
+
+ pm_runtime_put(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+ plda_pcie_host_deinit(&pcie->plda);
+ platform_set_drvdata(pdev, NULL);
+}
+
+static int starfive_pcie_suspend_noirq(struct device *dev)
+{
+ struct starfive_jh7110_pcie *pcie = dev_get_drvdata(dev);
+
+ clk_bulk_disable_unprepare(pcie->num_clks, pcie->clks);
+ starfive_pcie_disable_phy(pcie);
+
+ return 0;
+}
+
+static int starfive_pcie_resume_noirq(struct device *dev)
+{
+ struct starfive_jh7110_pcie *pcie = dev_get_drvdata(dev);
+ int ret;
+
+ ret = starfive_pcie_enable_phy(dev, pcie);
+ if (ret)
+ return ret;
+
+ ret = clk_bulk_prepare_enable(pcie->num_clks, pcie->clks);
+ if (ret) {
+ dev_err(dev, "failed to enable clocks\n");
+ starfive_pcie_disable_phy(pcie);
+ return ret;
+ }
+
+ return 0;
+}
+
+static const struct dev_pm_ops starfive_pcie_pm_ops = {
+ NOIRQ_SYSTEM_SLEEP_PM_OPS(starfive_pcie_suspend_noirq,
+ starfive_pcie_resume_noirq)
+};
+
+static const struct of_device_id starfive_pcie_of_match[] = {
+ { .compatible = "starfive,jh7110-pcie", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, starfive_pcie_of_match);
+
+static struct platform_driver starfive_pcie_driver = {
+ .driver = {
+ .name = "pcie-starfive",
+ .of_match_table = of_match_ptr(starfive_pcie_of_match),
+ .pm = pm_sleep_ptr(&starfive_pcie_pm_ops),
+ },
+ .probe = starfive_pcie_probe,
+ .remove_new = starfive_pcie_remove,
+};
+module_platform_driver(starfive_pcie_driver);
+
+MODULE_DESCRIPTION("StarFive JH7110 PCIe host driver");
+MODULE_LICENSE("GPL v2");
--
2.17.1



2024-02-29 14:31:02

by Lorenzo Pieralisi

[permalink] [raw]
Subject: Re: [PATCH v15,RESEND 21/23] PCI: starfive: Add JH7110 PCIe controller

On Tue, Feb 27, 2024 at 06:35:20PM +0800, Minda Chen wrote:
> Add StarFive JH7110 SoC PCIe controller platform driver codes, JH7110
> with PLDA host PCIe core.
>
> Signed-off-by: Minda Chen <[email protected]>
> Co-developed-by: Kevin Xie <[email protected]>
> Reviewed-by: Mason Huo <[email protected]>
> ---
> MAINTAINERS | 7 +
> drivers/pci/controller/plda/Kconfig | 12 +
> drivers/pci/controller/plda/Makefile | 1 +
> drivers/pci/controller/plda/pcie-plda.h | 71 ++-
> drivers/pci/controller/plda/pcie-starfive.c | 473 ++++++++++++++++++++
> 5 files changed, 563 insertions(+), 1 deletion(-)
> create mode 100644 drivers/pci/controller/plda/pcie-starfive.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index fc9576e69a71..d3b0a0fb754f 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -17078,6 +17078,13 @@ S: Maintained
> F: Documentation/devicetree/bindings/pci/socionext,uniphier-pcie*
> F: drivers/pci/controller/dwc/pcie-uniphier*
>
> +PCIE DRIVER FOR STARFIVE JH71x0
> +M: Kevin Xie <[email protected]>
> +L: [email protected]
> +S: Maintained
> +F: Documentation/devicetree/bindings/pci/starfive*
> +F: drivers/pci/controller/plda/pcie-starfive.c
> +
> PCIE DRIVER FOR ST SPEAR13XX
> M: Pratyush Anand <[email protected]>
> L: [email protected]
> diff --git a/drivers/pci/controller/plda/Kconfig b/drivers/pci/controller/plda/Kconfig
> index e54a82ee94f5..c0e14146d7e4 100644
> --- a/drivers/pci/controller/plda/Kconfig
> +++ b/drivers/pci/controller/plda/Kconfig
> @@ -15,4 +15,16 @@ config PCIE_MICROCHIP_HOST
> Say Y here if you want kernel to support the Microchip AXI PCIe
> Host Bridge driver.
>
> +config PCIE_STARFIVE_HOST
> + tristate "StarFive PCIe host controller"
> + depends on PCI_MSI && OF
> + depends on ARCH_STARFIVE || COMPILE_TEST
> + select PCIE_PLDA_HOST
> + help
> + Say Y here if you want to support the StarFive PCIe controller in
> + host mode. StarFive PCIe controller uses PLDA PCIe core.
> +
> + If you choose to build this driver as module it will be dynamically
> + linked and module will be called pcie-starfive.ko.
> +
> endmenu
> diff --git a/drivers/pci/controller/plda/Makefile b/drivers/pci/controller/plda/Makefile
> index 4340ab007f44..0ac6851bed48 100644
> --- a/drivers/pci/controller/plda/Makefile
> +++ b/drivers/pci/controller/plda/Makefile
> @@ -1,3 +1,4 @@
> # SPDX-License-Identifier: GPL-2.0
> obj-$(CONFIG_PCIE_PLDA_HOST) += pcie-plda-host.o
> obj-$(CONFIG_PCIE_MICROCHIP_HOST) += pcie-microchip-host.o
> +obj-$(CONFIG_PCIE_STARFIVE_HOST) += pcie-starfive.o
> diff --git a/drivers/pci/controller/plda/pcie-plda.h b/drivers/pci/controller/plda/pcie-plda.h
> index 7b69891700a4..04e385758a2f 100644
> --- a/drivers/pci/controller/plda/pcie-plda.h
> +++ b/drivers/pci/controller/plda/pcie-plda.h
> @@ -10,10 +10,20 @@
> #define PLDA_MAX_NUM_MSI_IRQS 32
>
> /* PCIe Bridge Phy Regs */
> +#define GEN_SETTINGS 0x80
> +#define RP_ENABLE 1
> +#define PCIE_PCI_IDS_DW1 0x9c
> +#define IDS_CLASS_CODE_SHIFT 16
> +#define REVISION_ID_MASK GENMASK(7, 0)
> +#define CLASS_CODE_ID_MASK GENMASK(31, 8)
> #define PCIE_PCI_IRQ_DW0 0xa8
> #define MSIX_CAP_MASK BIT(31)
> #define NUM_MSI_MSGS_MASK GENMASK(6, 4)
> #define NUM_MSI_MSGS_SHIFT 4
> +#define PCI_MISC 0xb4
> +#define PHY_FUNCTION_DIS BIT(15)
> +#define PCIE_WINROM 0xfc
> +#define PREF_MEM_WIN_64_SUPPORT BIT(3)
>
> #define IMASK_LOCAL 0x180
> #define DMA_END_ENGINE_0_MASK 0x00000000u
> @@ -65,6 +75,8 @@
> #define ISTATUS_HOST 0x18c
> #define IMSI_ADDR 0x190
> #define ISTATUS_MSI 0x194
> +#define PMSG_SUPPORT_RX 0x3f0
> +#define PMSG_LTR_SUPPORT BIT(2)
>
> /* PCIe Master table init defines */
> #define ATR0_PCIE_WIN0_SRCADDR_PARAM 0x600u
> @@ -86,6 +98,8 @@
> #define PCIE_TX_RX_INTERFACE 0x00000000u
> #define PCIE_CONFIG_INTERFACE 0x00000001u
>
> +#define CONFIG_SPACE_ADDR_OFFSET 0x1000u
> +
> #define ATR_ENTRY_SIZE 32
>
> enum plda_int_event {
> @@ -200,4 +214,59 @@ static inline void plda_set_default_msi(struct plda_msi *msi)
> msi->vector_phy = IMSI_ADDR;
> msi->num_vectors = PLDA_MAX_NUM_MSI_IRQS;
> }
> -#endif
> +
> +static inline void plda_pcie_enable_root_port(struct plda_pcie_rp *plda)
> +{
> + u32 value;
> +
> + value = readl_relaxed(plda->bridge_addr + GEN_SETTINGS);
> + value |= RP_ENABLE;
> + writel_relaxed(value, plda->bridge_addr + GEN_SETTINGS);
> +}
> +
> +static inline void plda_pcie_set_standard_class(struct plda_pcie_rp *plda)
> +{
> + u32 value;
> +
> + /* set class code and reserve revision id */
> + value = readl_relaxed(plda->bridge_addr + PCIE_PCI_IDS_DW1);
> + value &= REVISION_ID_MASK;
> + value |= (PCI_CLASS_BRIDGE_PCI << IDS_CLASS_CODE_SHIFT);
> + writel_relaxed(value, plda->bridge_addr + PCIE_PCI_IDS_DW1);
> +}
> +
> +static inline void plda_pcie_set_pref_win_64bit(struct plda_pcie_rp *plda)
> +{
> + u32 value;
> +
> + value = readl_relaxed(plda->bridge_addr + PCIE_WINROM);
> + value |= PREF_MEM_WIN_64_SUPPORT;
> + writel_relaxed(value, plda->bridge_addr + PCIE_WINROM);
> +}

What does this do ?

> +static inline void plda_pcie_disable_ltr(struct plda_pcie_rp *plda)
> +{
> + u32 value;
> +
> + value = readl_relaxed(plda->bridge_addr + PMSG_SUPPORT_RX);
> + value &= ~PMSG_LTR_SUPPORT;
> + writel_relaxed(value, plda->bridge_addr + PMSG_SUPPORT_RX);
> +}
> +
> +static inline void plda_pcie_disable_func(struct plda_pcie_rp *plda)
> +{
> + u32 value;
> +
> + value = readl_relaxed(plda->bridge_addr + PCI_MISC);
> + value |= PHY_FUNCTION_DIS;
> + writel_relaxed(value, plda->bridge_addr + PCI_MISC);
> +}
> +
> +static inline void plda_pcie_write_rc_bar(struct plda_pcie_rp *plda, u64 val)
> +{
> + void __iomem *addr = plda->bridge_addr + CONFIG_SPACE_ADDR_OFFSET;
> +
> + writel_relaxed(lower_32_bits(val), addr + PCI_BASE_ADDRESS_0);
> + writel_relaxed(upper_32_bits(val), addr + PCI_BASE_ADDRESS_1);
> +}
> +#endif /* _PCIE_PLDA_H */
> diff --git a/drivers/pci/controller/plda/pcie-starfive.c b/drivers/pci/controller/plda/pcie-starfive.c
> new file mode 100644
> index 000000000000..9bb9f0e29565
> --- /dev/null
> +++ b/drivers/pci/controller/plda/pcie-starfive.c
> @@ -0,0 +1,473 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * PCIe host controller driver for StarFive JH7110 Soc.
> + *
> + * Copyright (C) 2023 StarFive Technology Co., Ltd.
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/interrupt.h>
> +#include <linux/kernel.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/module.h>
> +#include <linux/of_address.h>
> +#include <linux/of_irq.h>
> +#include <linux/of_pci.h>
> +#include <linux/pci.h>
> +#include <linux/phy/phy.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/regmap.h>
> +#include <linux/reset.h>
> +#include "../../pci.h"
> +
> +#include "pcie-plda.h"
> +
> +#define PCIE_FUNC_NUM 4
> +
> +/* system control */
> +#define STG_SYSCON_PCIE0_BASE 0x48
> +#define STG_SYSCON_PCIE1_BASE 0x1f8
> +
> +#define STG_SYSCON_AR_OFFSET 0x78
> +#define STG_SYSCON_AXI4_SLVL_AR_MASK GENMASK(22, 8)
> +#define STG_SYSCON_AXI4_SLVL_PHY_AR(x) FIELD_PREP(GENMASK(20, 17), x)
> +#define STG_SYSCON_AW_OFFSET 0x7c
> +#define STG_SYSCON_AXI4_SLVL_AW_MASK GENMASK(14, 0)
> +#define STG_SYSCON_AXI4_SLVL_PHY_AW(x) FIELD_PREP(GENMASK(12, 9), x)
> +#define STG_SYSCON_CLKREQ BIT(22)
> +#define STG_SYSCON_CKREF_SRC_MASK GENMASK(19, 18)
> +#define STG_SYSCON_RP_NEP_OFFSET 0xe8
> +#define STG_SYSCON_K_RP_NEP BIT(8)
> +#define STG_SYSCON_LNKSTA_OFFSET 0x170
> +#define DATA_LINK_ACTIVE BIT(5)
> +
> +/* Parameters for the waiting for link up routine */
> +#define LINK_WAIT_MAX_RETRIES 10
> +#define LINK_WAIT_USLEEP_MIN 90000
> +#define LINK_WAIT_USLEEP_MAX 100000
> +
> +struct starfive_jh7110_pcie {
> + struct plda_pcie_rp plda;
> + struct reset_control *resets;
> + struct clk_bulk_data *clks;
> + struct regmap *reg_syscon;
> + struct gpio_desc *power_gpio;
> + struct gpio_desc *reset_gpio;
> + struct phy *phy;
> +
> + unsigned int stg_pcie_base;
> + int num_clks;
> +};
> +
> +/*
> + * The BAR0/1 of bridge should be hidden during enumeration to
> + * avoid the sizing and resource allocation by PCIe core.

Please explain. This is what's preventing this driver to re-use
the PCI_HOST_COMMON infrastructure and it is unclear why.

> + */
> +static bool starfive_pcie_hide_rc_bar(struct pci_bus *bus, unsigned int devfn,
> + int offset)
> +{
> + if (pci_is_root_bus(bus) && !devfn &&
> + (offset == PCI_BASE_ADDRESS_0 || offset == PCI_BASE_ADDRESS_1))
> + return true;
> +
> + return false;
> +}
> +
> +static int starfive_pcie_config_write(struct pci_bus *bus, unsigned int devfn,
> + int where, int size, u32 value)
> +{
> + if (starfive_pcie_hide_rc_bar(bus, devfn, where))
> + return PCIBIOS_SUCCESSFUL;
> +
> + return pci_generic_config_write(bus, devfn, where, size, value);
> +}
> +
> +static int starfive_pcie_config_read(struct pci_bus *bus, unsigned int devfn,
> + int where, int size, u32 *value)
> +{
> + if (starfive_pcie_hide_rc_bar(bus, devfn, where)) {
> + *value = 0;
> + return PCIBIOS_SUCCESSFUL;
> + }
> +
> + return pci_generic_config_read(bus, devfn, where, size, value);
> +}
> +
> +static int starfive_pcie_parse_dt(struct starfive_jh7110_pcie *pcie,
> + struct device *dev)
> +{
> + int domain_nr;
> +
> + pcie->num_clks = devm_clk_bulk_get_all(dev, &pcie->clks);
> + if (pcie->num_clks < 0)
> + return dev_err_probe(dev, pcie->num_clks,
> + "failed to get pcie clocks\n");
> +
> + pcie->resets = devm_reset_control_array_get_exclusive(dev);
> + if (IS_ERR(pcie->resets))
> + return dev_err_probe(dev, PTR_ERR(pcie->resets),
> + "failed to get pcie resets");
> +
> + pcie->reg_syscon =
> + syscon_regmap_lookup_by_phandle(dev->of_node,
> + "starfive,stg-syscon");
> +
> + if (IS_ERR(pcie->reg_syscon))
> + return dev_err_probe(dev, PTR_ERR(pcie->reg_syscon),
> + "failed to parse starfive,stg-syscon\n");
> +
> + pcie->phy = devm_phy_optional_get(dev, NULL);
> + if (IS_ERR(pcie->phy))
> + return dev_err_probe(dev, PTR_ERR(pcie->phy),
> + "failed to get pcie phy\n");
> +
> + domain_nr = of_get_pci_domain_nr(dev->of_node);
> +
> + if (domain_nr < 0 || domain_nr > 1)
> + return dev_err_probe(dev, -ENODEV,
> + "failed to get valid pcie domain\n");
> +
> + if (domain_nr == 0)
> + pcie->stg_pcie_base = STG_SYSCON_PCIE0_BASE;
> + else
> + pcie->stg_pcie_base = STG_SYSCON_PCIE1_BASE;

I don't agree with this. The domain number is a software allocated
value attached to a controller. It is written nowhere that you can't
swap them and leave this code path broken.

> + pcie->reset_gpio = devm_gpiod_get_optional(dev, "perst",
> + GPIOD_OUT_HIGH);
> + if (IS_ERR(pcie->reset_gpio))
> + return dev_err_probe(dev, PTR_ERR(pcie->reset_gpio),
> + "failed to get perst-gpio\n");
> +
> + pcie->power_gpio = devm_gpiod_get_optional(dev, "enable",
> + GPIOD_OUT_LOW);
> + if (IS_ERR(pcie->power_gpio))
> + return dev_err_probe(dev, PTR_ERR(pcie->power_gpio),
> + "failed to get power-gpio\n");
> +
> + return 0;
> +}
> +
> +static struct pci_ops starfive_pcie_ops = {
> + .map_bus = plda_pcie_map_bus,

It looks like this is an ECAM driver with the read/config quirks
for read/write in the method below. Please explain why they are needed.

> + .read = starfive_pcie_config_read,
> + .write = starfive_pcie_config_write,
> +};
> +
> +static int starfive_pcie_clk_rst_init(struct starfive_jh7110_pcie *pcie)
> +{
> + struct device *dev = pcie->plda.dev;
> + int ret;
> +
> + ret = clk_bulk_prepare_enable(pcie->num_clks, pcie->clks);
> + if (ret)
> + return dev_err_probe(dev, ret, "failed to enable clocks\n");
> +
> + ret = reset_control_deassert(pcie->resets);
> + if (ret) {
> + clk_bulk_disable_unprepare(pcie->num_clks, pcie->clks);
> + dev_err_probe(dev, ret, "failed to deassert resets\n");
> + }
> +
> + return ret;
> +}
> +
> +static void starfive_pcie_clk_rst_deinit(struct starfive_jh7110_pcie *pcie)
> +{
> + reset_control_assert(pcie->resets);
> + clk_bulk_disable_unprepare(pcie->num_clks, pcie->clks);
> +}
> +
> +static bool starfive_pcie_link_up(struct plda_pcie_rp *plda)
> +{
> + struct starfive_jh7110_pcie *pcie =
> + container_of(plda, struct starfive_jh7110_pcie, plda);
> + int ret;
> + u32 stg_reg_val;
> +
> + ret = regmap_read(pcie->reg_syscon,
> + pcie->stg_pcie_base + STG_SYSCON_LNKSTA_OFFSET,
> + &stg_reg_val);
> + if (ret) {
> + dev_err(pcie->plda.dev, "failed to read link status\n");
> + return false;
> + }
> +
> + return !!(stg_reg_val & DATA_LINK_ACTIVE);
> +}
> +
> +static int starfive_pcie_host_wait_for_link(struct starfive_jh7110_pcie *pcie)
> +{
> + int retries;
> +
> + /* Check if the link is up or not */
> + for (retries = 0; retries < LINK_WAIT_MAX_RETRIES; retries++) {
> + if (starfive_pcie_link_up(&pcie->plda)) {
> + dev_info(pcie->plda.dev, "port link up\n");
> + return 0;
> + }
> + usleep_range(LINK_WAIT_USLEEP_MIN, LINK_WAIT_USLEEP_MAX);
> + }
> +
> + return -ETIMEDOUT;
> +}
> +
> +static int starfive_pcie_enable_phy(struct device *dev,
> + struct starfive_jh7110_pcie *pcie)
> +{
> + int ret;
> +
> + if (!pcie->phy)
> + return 0;
> +
> + ret = phy_init(pcie->phy);
> + if (ret)
> + return dev_err_probe(dev, ret,
> + "failed to initialize pcie phy\n");
> +
> + ret = phy_set_mode(pcie->phy, PHY_MODE_PCIE);
> + if (ret) {
> + dev_err_probe(dev, ret, "failed to set pcie mode\n");
> + goto err_phy_on;
> + }
> +
> + ret = phy_power_on(pcie->phy);
> + if (ret) {
> + dev_err_probe(dev, ret, "failed to power on pcie phy\n");
> + goto err_phy_on;
> + }
> +
> + return 0;
> +
> +err_phy_on:
> + phy_exit(pcie->phy);
> + return ret;
> +}
> +
> +static void starfive_pcie_disable_phy(struct starfive_jh7110_pcie *pcie)
> +{
> + phy_power_off(pcie->phy);
> + phy_exit(pcie->phy);
> +}
> +
> +static void starfive_pcie_host_deinit(struct plda_pcie_rp *plda)
> +{
> + struct starfive_jh7110_pcie *pcie =
> + container_of(plda, struct starfive_jh7110_pcie, plda);
> +
> + starfive_pcie_clk_rst_deinit(pcie);
> + if (pcie->power_gpio)
> + gpiod_set_value_cansleep(pcie->power_gpio, 0);
> + starfive_pcie_disable_phy(pcie);
> +}
> +
> +static int starfive_pcie_host_init(struct plda_pcie_rp *plda)
> +{
> + struct starfive_jh7110_pcie *pcie =
> + container_of(plda, struct starfive_jh7110_pcie, plda);
> + struct device *dev = plda->dev;
> + int ret;
> + int i;
> +
> + ret = starfive_pcie_enable_phy(dev, pcie);
> + if (ret)
> + return ret;
> +
> + regmap_update_bits(pcie->reg_syscon,
> + pcie->stg_pcie_base + STG_SYSCON_RP_NEP_OFFSET,
> + STG_SYSCON_K_RP_NEP, STG_SYSCON_K_RP_NEP);
> +
> + regmap_update_bits(pcie->reg_syscon,
> + pcie->stg_pcie_base + STG_SYSCON_AW_OFFSET,
> + STG_SYSCON_CKREF_SRC_MASK,
> + FIELD_PREP(STG_SYSCON_CKREF_SRC_MASK, 2));
> +
> + regmap_update_bits(pcie->reg_syscon,
> + pcie->stg_pcie_base + STG_SYSCON_AW_OFFSET,
> + STG_SYSCON_CLKREQ, STG_SYSCON_CLKREQ);
> +
> + ret = starfive_pcie_clk_rst_init(pcie);
> + if (ret)
> + return ret;
> +
> + if (pcie->power_gpio)
> + gpiod_set_value_cansleep(pcie->power_gpio, 1);
> +
> + if (pcie->reset_gpio)
> + gpiod_set_value_cansleep(pcie->reset_gpio, 1);
> +
> + /* Disable physical functions except #0 */
> + for (i = 1; i < PCIE_FUNC_NUM; i++) {
> + regmap_update_bits(pcie->reg_syscon,
> + pcie->stg_pcie_base + STG_SYSCON_AR_OFFSET,
> + STG_SYSCON_AXI4_SLVL_AR_MASK,
> + STG_SYSCON_AXI4_SLVL_PHY_AR(i));
> +
> + regmap_update_bits(pcie->reg_syscon,
> + pcie->stg_pcie_base + STG_SYSCON_AW_OFFSET,
> + STG_SYSCON_AXI4_SLVL_AW_MASK,
> + STG_SYSCON_AXI4_SLVL_PHY_AW(i));
> +
> + plda_pcie_disable_func(plda);
> + }
> +
> + regmap_update_bits(pcie->reg_syscon,
> + pcie->stg_pcie_base + STG_SYSCON_AR_OFFSET,
> + STG_SYSCON_AXI4_SLVL_AR_MASK, 0);
> + regmap_update_bits(pcie->reg_syscon,
> + pcie->stg_pcie_base + STG_SYSCON_AW_OFFSET,
> + STG_SYSCON_AXI4_SLVL_AW_MASK, 0);
> +
> + plda_pcie_enable_root_port(plda);
> + plda_pcie_write_rc_bar(plda, 0);
> +
> + /* PCIe PCI Standard Configuration Identification Settings. */
> + plda_pcie_set_standard_class(plda);
> +
> + /*
> + * The LTR message forwarding of PCIe Message Reception was set by core

"LTR message forwarding of PCIe Message Reception".

What is this referring to ?

Thanks,
Lorenzo

> + * as default, but the forward id & addr are also need to be reset.
> + * If we do not disable LTR message forwarding here, or set a legal
> + * forwarding address, the kernel will get stuck after the driver probe.
> + * To workaround, disable the LTR message forwarding support on
> + * PCIe Message Reception.
> + */
> + plda_pcie_disable_ltr(plda);
> +
> + /* Prefetchable memory window 64-bit addressing support */
> + plda_pcie_set_pref_win_64bit(plda);
> +
> + /*
> + * Ensure that PERST has been asserted for at least 100 ms,
> + * the sleep value is T_PVPERL from PCIe CEM spec r2.0 (Table 2-4)
> + */
> + msleep(100);
> + if (pcie->reset_gpio)
> + gpiod_set_value_cansleep(pcie->reset_gpio, 0);
> +
> + /*
> + * With a Downstream Port (<=5GT/s), software must wait a minimum
> + * of 100ms following exit from a conventional reset before
> + * sending a configuration request to the device.
> + */
> + msleep(PCIE_RESET_CONFIG_DEVICE_WAIT_MS);
> +
> + if (starfive_pcie_host_wait_for_link(pcie))
> + dev_info(dev, "port link down\n");
> +
> + return 0;
> +}
> +
> +static const struct plda_pcie_host_ops sf_host_ops = {
> + .host_init = starfive_pcie_host_init,
> + .host_deinit = starfive_pcie_host_deinit,
> +};
> +
> +static const struct plda_event stf_pcie_event = {
> + .intx_event = EVENT_PM_MSI_INT_INTX,
> + .msi_event = EVENT_PM_MSI_INT_MSI
> +};
> +
> +static int starfive_pcie_probe(struct platform_device *pdev)
> +{
> + struct starfive_jh7110_pcie *pcie;
> + struct device *dev = &pdev->dev;
> + struct plda_pcie_rp *plda;
> + int ret;
> +
> + pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL);
> + if (!pcie)
> + return -ENOMEM;
> +
> + plda = &pcie->plda;
> + plda->dev = dev;
> +
> + ret = starfive_pcie_parse_dt(pcie, dev);
> + if (ret)
> + return ret;
> +
> + plda->host_ops = &sf_host_ops;
> + plda->num_events = PLDA_MAX_EVENT_NUM;
> + /* mask doorbell event */
> + plda->events_bitmap = GENMASK(PLDA_INT_EVENT_NUM - 1, 0)
> + & ~BIT(PLDA_AXI_DOORBELL)
> + & ~BIT(PLDA_PCIE_DOORBELL);
> + plda->events_bitmap <<= PLDA_NUM_DMA_EVENTS;
> + ret = plda_pcie_host_init(&pcie->plda, &starfive_pcie_ops,
> + &stf_pcie_event);
> + if (ret)
> + return ret;
> +
> + pm_runtime_enable(&pdev->dev);
> + pm_runtime_get_sync(&pdev->dev);
> + platform_set_drvdata(pdev, pcie);
> +
> + return 0;
> +}
> +
> +static void starfive_pcie_remove(struct platform_device *pdev)
> +{
> + struct starfive_jh7110_pcie *pcie = platform_get_drvdata(pdev);
> +
> + pm_runtime_put(&pdev->dev);
> + pm_runtime_disable(&pdev->dev);
> + plda_pcie_host_deinit(&pcie->plda);
> + platform_set_drvdata(pdev, NULL);
> +}
> +
> +static int starfive_pcie_suspend_noirq(struct device *dev)
> +{
> + struct starfive_jh7110_pcie *pcie = dev_get_drvdata(dev);
> +
> + clk_bulk_disable_unprepare(pcie->num_clks, pcie->clks);
> + starfive_pcie_disable_phy(pcie);
> +
> + return 0;
> +}
> +
> +static int starfive_pcie_resume_noirq(struct device *dev)
> +{
> + struct starfive_jh7110_pcie *pcie = dev_get_drvdata(dev);
> + int ret;
> +
> + ret = starfive_pcie_enable_phy(dev, pcie);
> + if (ret)
> + return ret;
> +
> + ret = clk_bulk_prepare_enable(pcie->num_clks, pcie->clks);
> + if (ret) {
> + dev_err(dev, "failed to enable clocks\n");
> + starfive_pcie_disable_phy(pcie);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static const struct dev_pm_ops starfive_pcie_pm_ops = {
> + NOIRQ_SYSTEM_SLEEP_PM_OPS(starfive_pcie_suspend_noirq,
> + starfive_pcie_resume_noirq)
> +};
> +
> +static const struct of_device_id starfive_pcie_of_match[] = {
> + { .compatible = "starfive,jh7110-pcie", },
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, starfive_pcie_of_match);
> +
> +static struct platform_driver starfive_pcie_driver = {
> + .driver = {
> + .name = "pcie-starfive",
> + .of_match_table = of_match_ptr(starfive_pcie_of_match),
> + .pm = pm_sleep_ptr(&starfive_pcie_pm_ops),
> + },
> + .probe = starfive_pcie_probe,
> + .remove_new = starfive_pcie_remove,
> +};
> +module_platform_driver(starfive_pcie_driver);
> +
> +MODULE_DESCRIPTION("StarFive JH7110 PCIe host driver");
> +MODULE_LICENSE("GPL v2");
> --
> 2.17.1
>
>
> _______________________________________________
> linux-riscv mailing list
> [email protected]
> http://lists.infradead.org/mailman/listinfo/linux-riscv

2024-03-04 13:25:34

by Kevin Xie

[permalink] [raw]
Subject: Re: [PATCH v15,RESEND 21/23] PCI: starfive: Add JH7110 PCIe controller

> On Tue, Feb 27, 2024 at 06:35:20PM +0800, Minda Chen wrote:
> > Add StarFive JH7110 SoC PCIe controller platform driver codes, JH7110
> > with PLDA host PCIe core.
> >
> > Signed-off-by: Minda Chen <[email protected]>
> > Co-developed-by: Kevin Xie <[email protected]>
> > Reviewed-by: Mason Huo <[email protected]>
> > ---
> > MAINTAINERS | 7 +
> > drivers/pci/controller/plda/Kconfig | 12 +
> > drivers/pci/controller/plda/Makefile | 1 +
> > drivers/pci/controller/plda/pcie-plda.h | 71 ++-
> > drivers/pci/controller/plda/pcie-starfive.c | 473
> > ++++++++++++++++++++
> > 5 files changed, 563 insertions(+), 1 deletion(-) create mode 100644
> > drivers/pci/controller/plda/pcie-starfive.c
> >
> > diff --git a/MAINTAINERS b/MAINTAINERS index
> > fc9576e69a71..d3b0a0fb754f 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -17078,6 +17078,13 @@ S: Maintained
> > F: Documentation/devicetree/bindings/pci/socionext,uniphier-pcie*
> > F: drivers/pci/controller/dwc/pcie-uniphier*
> >
> > +PCIE DRIVER FOR STARFIVE JH71x0
> > +M: Kevin Xie <[email protected]>
> > +L: [email protected]
> > +S: Maintained
> > +F: Documentation/devicetree/bindings/pci/starfive*
> > +F: drivers/pci/controller/plda/pcie-starfive.c
> > +
> > PCIE DRIVER FOR ST SPEAR13XX
> > M: Pratyush Anand <[email protected]>
> > L: [email protected]

> > diff --git a/drivers/pci/controller/plda/pcie-plda.h
> > b/drivers/pci/controller/plda/pcie-plda.h
> > index 7b69891700a4..04e385758a2f 100644
> > --- a/drivers/pci/controller/plda/pcie-plda.h
> > +++ b/drivers/pci/controller/plda/pcie-plda.h
> > @@ -10,10 +10,20 @@
> > #define PLDA_MAX_NUM_MSI_IRQS 32
> >
> > /* PCIe Bridge Phy Regs */
> > +#define GEN_SETTINGS 0x80
> > +#define RP_ENABLE 1
> > +#define PCIE_PCI_IDS_DW1 0x9c
> > +#define IDS_CLASS_CODE_SHIFT 16
> > +#define REVISION_ID_MASK GENMASK(7, 0)
> > +#define CLASS_CODE_ID_MASK GENMASK(31, 8)
> > #define PCIE_PCI_IRQ_DW0 0xa8
> > #define MSIX_CAP_MASK BIT(31)
> > #define NUM_MSI_MSGS_MASK GENMASK(6, 4)
> > #define NUM_MSI_MSGS_SHIFT 4
> > +#define PCI_MISC 0xb4
> > +#define PHY_FUNCTION_DIS BIT(15)
> > +#define PCIE_WINROM 0xfc
> > +#define PREF_MEM_WIN_64_SUPPORT BIT(3)
> >
> > #define IMASK_LOCAL 0x180
> > #define DMA_END_ENGINE_0_MASK 0x00000000u
> > @@ -65,6 +75,8 @@
> > #define ISTATUS_HOST 0x18c
> > #define IMSI_ADDR 0x190
> > #define ISTATUS_MSI 0x194
> > +#define PMSG_SUPPORT_RX 0x3f0
> > +#define PMSG_LTR_SUPPORT BIT(2)
> >
> > /* PCIe Master table init defines */
> > #define ATR0_PCIE_WIN0_SRCADDR_PARAM 0x600u
> > @@ -86,6 +98,8 @@
> > #define PCIE_TX_RX_INTERFACE 0x00000000u
> > #define PCIE_CONFIG_INTERFACE 0x00000001u
> >
> > +#define CONFIG_SPACE_ADDR_OFFSET 0x1000u
> > +
> > #define ATR_ENTRY_SIZE 32
> >
> > enum plda_int_event {
> > @@ -200,4 +214,59 @@ static inline void plda_set_default_msi(struct
> plda_msi *msi)
> > msi->vector_phy = IMSI_ADDR;
> > msi->num_vectors = PLDA_MAX_NUM_MSI_IRQS; } -#endif
> > +
> > +static inline void plda_pcie_enable_root_port(struct plda_pcie_rp
> > +*plda) {
> > + u32 value;
> > +
> > + value = readl_relaxed(plda->bridge_addr + GEN_SETTINGS);
> > + value |= RP_ENABLE;
> > + writel_relaxed(value, plda->bridge_addr + GEN_SETTINGS); }
> > +
> > +static inline void plda_pcie_set_standard_class(struct plda_pcie_rp
> > +*plda) {
> > + u32 value;
> > +
> > + /* set class code and reserve revision id */
> > + value = readl_relaxed(plda->bridge_addr + PCIE_PCI_IDS_DW1);
> > + value &= REVISION_ID_MASK;
> > + value |= (PCI_CLASS_BRIDGE_PCI << IDS_CLASS_CODE_SHIFT);
> > + writel_relaxed(value, plda->bridge_addr + PCIE_PCI_IDS_DW1); }
> > +
> > +static inline void plda_pcie_set_pref_win_64bit(struct plda_pcie_rp
> > +*plda) {
> > + u32 value;
> > +
> > + value = readl_relaxed(plda->bridge_addr + PCIE_WINROM);
> > + value |= PREF_MEM_WIN_64_SUPPORT;
> > + writel_relaxed(value, plda->bridge_addr + PCIE_WINROM); }
>
> What does this do ?
>

This is an internal register to enable the prefetchable memory window
64-bit addressing support. ( disabled by default)
After this enable configuration, the address translation config in DTS
and ATU about 64-bit prefetchable memory are useful.

I will add the annotation here in the next version.

> > +static inline void plda_pcie_disable_ltr(struct plda_pcie_rp *plda) {
> > + u32 value;
> > +
> > + value = readl_relaxed(plda->bridge_addr + PMSG_SUPPORT_RX);
> > + value &= ~PMSG_LTR_SUPPORT;
> > + writel_relaxed(value, plda->bridge_addr + PMSG_SUPPORT_RX); }
> > +
> > +static inline void plda_pcie_disable_func(struct plda_pcie_rp *plda)
> > +{
> > + u32 value;
> > +
> > + value = readl_relaxed(plda->bridge_addr + PCI_MISC);
> > + value |= PHY_FUNCTION_DIS;
> > + writel_relaxed(value, plda->bridge_addr + PCI_MISC); }
> > +
> > +static inline void plda_pcie_write_rc_bar(struct plda_pcie_rp *plda,
> > +u64 val) {
> > + void __iomem *addr = plda->bridge_addr +
> CONFIG_SPACE_ADDR_OFFSET;
> > +
> > + writel_relaxed(lower_32_bits(val), addr + PCI_BASE_ADDRESS_0);
> > + writel_relaxed(upper_32_bits(val), addr + PCI_BASE_ADDRESS_1); }
> > +#endif /* _PCIE_PLDA_H */
> > diff --git a/drivers/pci/controller/plda/pcie-starfive.c
> > b/drivers/pci/controller/plda/pcie-starfive.c
> > new file mode 100644
> > index 000000000000..9bb9f0e29565
> > --- /dev/null
> > +++ b/drivers/pci/controller/plda/pcie-starfive.c
> > @@ -0,0 +1,473 @@
> > +// SPDX-License-Identifier: GPL-2.0+
> > +/*
> > + * PCIe host controller driver for StarFive JH7110 Soc.
> > + *
> > + * Copyright (C) 2023 StarFive Technology Co., Ltd.
> > + */
> > +
> > +#include <linux/bitfield.h>
> > +#include <linux/clk.h>
> > +#include <linux/delay.h>
> > +#include <linux/gpio/consumer.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/kernel.h>
> > +#include <linux/mfd/syscon.h>
> > +#include <linux/module.h>
> > +#include <linux/of_address.h>
> > +#include <linux/of_irq.h>
> > +#include <linux/of_pci.h>
> > +#include <linux/pci.h>
> > +#include <linux/phy/phy.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/pm_runtime.h>
> > +#include <linux/regmap.h>
> > +#include <linux/reset.h>
> > +#include "../../pci.h"
> > +
> > +#include "pcie-plda.h"
> > +
> > +#define PCIE_FUNC_NUM 4
> > +
> > +/* system control */
> > +#define STG_SYSCON_PCIE0_BASE 0x48
> > +#define STG_SYSCON_PCIE1_BASE 0x1f8
> > +
> > +#define STG_SYSCON_AR_OFFSET 0x78
> > +#define STG_SYSCON_AXI4_SLVL_AR_MASK GENMASK(22, 8)
> > +#define STG_SYSCON_AXI4_SLVL_PHY_AR(x)
> FIELD_PREP(GENMASK(20, 17), x)
> > +#define STG_SYSCON_AW_OFFSET 0x7c
> > +#define STG_SYSCON_AXI4_SLVL_AW_MASK GENMASK(14, 0)
> > +#define STG_SYSCON_AXI4_SLVL_PHY_AW(x)
> FIELD_PREP(GENMASK(12, 9), x)
> > +#define STG_SYSCON_CLKREQ BIT(22)
> > +#define STG_SYSCON_CKREF_SRC_MASK GENMASK(19, 18)
> > +#define STG_SYSCON_RP_NEP_OFFSET 0xe8
> > +#define STG_SYSCON_K_RP_NEP BIT(8)
> > +#define STG_SYSCON_LNKSTA_OFFSET 0x170
> > +#define DATA_LINK_ACTIVE BIT(5)
> > +
> > +/* Parameters for the waiting for link up routine */
> > +#define LINK_WAIT_MAX_RETRIES 10
> > +#define LINK_WAIT_USLEEP_MIN 90000
> > +#define LINK_WAIT_USLEEP_MAX 100000
> > +
> > +struct starfive_jh7110_pcie {
> > + struct plda_pcie_rp plda;
> > + struct reset_control *resets;
> > + struct clk_bulk_data *clks;
> > + struct regmap *reg_syscon;
> > + struct gpio_desc *power_gpio;
> > + struct gpio_desc *reset_gpio;
> > + struct phy *phy;
> > +
> > + unsigned int stg_pcie_base;
> > + int num_clks;
> > +};
> > +
> > +/*
> > + * The BAR0/1 of bridge should be hidden during enumeration to
> > + * avoid the sizing and resource allocation by PCIe core.
>
> Please explain. This is what's preventing this driver to re-use the
> PCI_HOST_COMMON infrastructure and it is unclear why.
>

Sorry, we didn't explain it clearly enough here.
JH7110 PCIe port BAR0/1 is configured as 64-bit prefetchable memory
space, PCIe read and write requests targeting BAR0/1 are routed to so
called 'Bridge Configuration space' in PLDA datasheet, which contains
the bridge internal registers, such as interrupt, DMA & ATU registers...

JH7110 can access the Bridge Configuration space by local bus, and don`t
want the bridge internal registers accessed by the DMA from EP devices.
Thus, they are unimplemented and should be hidden.

I will modify the annotation in next version if you think it is ok.

> > + */
> > +static bool starfive_pcie_hide_rc_bar(struct pci_bus *bus, unsigned int
> devfn,
> > + int offset)
> > +{
> > + if (pci_is_root_bus(bus) && !devfn &&
> > + (offset == PCI_BASE_ADDRESS_0 || offset == PCI_BASE_ADDRESS_1))
> > + return true;
> > +
> > + return false;
> > +}
> > +
> > +static int starfive_pcie_config_write(struct pci_bus *bus, unsigned int devfn,
> > + int where, int size, u32 value) {
> > + if (starfive_pcie_hide_rc_bar(bus, devfn, where))
> > + return PCIBIOS_SUCCESSFUL;
> > +
> > + return pci_generic_config_write(bus, devfn, where, size, value); }
> > +
> > +static int starfive_pcie_config_read(struct pci_bus *bus, unsigned int devfn,
> > + int where, int size, u32 *value) {
> > + if (starfive_pcie_hide_rc_bar(bus, devfn, where)) {
> > + *value = 0;
> > + return PCIBIOS_SUCCESSFUL;
> > + }
> > +
> > + return pci_generic_config_read(bus, devfn, where, size, value); }
> > +
> > +static int starfive_pcie_parse_dt(struct starfive_jh7110_pcie *pcie,
> > + struct device *dev)
> > +{
> > + int domain_nr;
> > +
> > + pcie->num_clks = devm_clk_bulk_get_all(dev, &pcie->clks);
> > + if (pcie->num_clks < 0)
> > + return dev_err_probe(dev, pcie->num_clks,
> > + "failed to get pcie clocks\n");
> > +
> > + pcie->resets = devm_reset_control_array_get_exclusive(dev);
> > + if (IS_ERR(pcie->resets))
> > + return dev_err_probe(dev, PTR_ERR(pcie->resets),
> > + "failed to get pcie resets");
> > +
> > + pcie->reg_syscon =
> > + syscon_regmap_lookup_by_phandle(dev->of_node,
> > + "starfive,stg-syscon");
> > +
> > + if (IS_ERR(pcie->reg_syscon))
> > + return dev_err_probe(dev, PTR_ERR(pcie->reg_syscon),
> > + "failed to parse starfive,stg-syscon\n");
> > +
> > + pcie->phy = devm_phy_optional_get(dev, NULL);
> > + if (IS_ERR(pcie->phy))
> > + return dev_err_probe(dev, PTR_ERR(pcie->phy),
> > + "failed to get pcie phy\n");
> > +
> > + domain_nr = of_get_pci_domain_nr(dev->of_node);
> > +
> > + if (domain_nr < 0 || domain_nr > 1)
> > + return dev_err_probe(dev, -ENODEV,
> > + "failed to get valid pcie domain\n");
> > +
> > + if (domain_nr == 0)
> > + pcie->stg_pcie_base = STG_SYSCON_PCIE0_BASE;
> > + else
> > + pcie->stg_pcie_base = STG_SYSCON_PCIE1_BASE;
>
> I don't agree with this. The domain number is a software allocated value
> attached to a controller. It is written nowhere that you can't swap them and
> leave this code path broken.
>

We set 'linux,pci-domain = <0>' in our pcie0 DTS node, and <1> for
pcie1. The value should be static now.

As the STG system controller defines different bases in PCIe RP0 & RP1,
we have to identify which controller is doing the hardware initialization.
We discussed this before with other maintainers, do you have a better
suggestion?

> > + pcie->reset_gpio = devm_gpiod_get_optional(dev, "perst",
> > + GPIOD_OUT_HIGH);
> > + if (IS_ERR(pcie->reset_gpio))
> > + return dev_err_probe(dev, PTR_ERR(pcie->reset_gpio),
> > + "failed to get perst-gpio\n");
> > +
> > + pcie->power_gpio = devm_gpiod_get_optional(dev, "enable",
> > + GPIOD_OUT_LOW);
> > + if (IS_ERR(pcie->power_gpio))
> > + return dev_err_probe(dev, PTR_ERR(pcie->power_gpio),
> > + "failed to get power-gpio\n");
> > +
> > + return 0;
> > +}
> > +
> > +static struct pci_ops starfive_pcie_ops = {
> > + .map_bus = plda_pcie_map_bus,
>
> It looks like this is an ECAM driver with the read/config quirks for read/write in
> the method below. Please explain why they are needed.
>

Yes, that's for the hide RC BAR operations mentioned above.

> > + .read = starfive_pcie_config_read,
> > + .write = starfive_pcie_config_write,
> > +};
> > +
> > +static int starfive_pcie_clk_rst_init(struct starfive_jh7110_pcie
> > +*pcie) {
> > + struct device *dev = pcie->plda.dev;
> > + int ret;
> > +
> > + /* PCIe PCI Standard Configuration Identification Settings. */
> > + plda_pcie_set_standard_class(plda);
> > +
> > + /*
> > + * The LTR message forwarding of PCIe Message Reception was set by
> > +core
>
> "LTR message forwarding of PCIe Message Reception".
>
> What is this referring to ?
>

Sorry, this sentence is ambiguous.
"PCIe Message Reception" is a register to enable the function about forwarding
specific PCIe messages to AXI application, such as ATS/LTR/OBFF messages...
Here we clear bit 2 to disable the LTR message forwarding to the AXI application.

I will modify the annotation in next version if you think it is ok.

Thank you for your valuable comments.
Kevin.

> Thanks,
> Lorenzo
>
> > + * as default, but the forward id & addr are also need to be reset.
> > + * If we do not disable LTR message forwarding here, or set a legal
> > + * forwarding address, the kernel will get stuck after the driver probe.
> > + * To workaround, disable the LTR message forwarding support on
> > + * PCIe Message Reception.
> > + */
> > + plda_pcie_disable_ltr(plda);
> > +
> > + /* Prefetchable memory window 64-bit addressing support */
> > + plda_pcie_set_pref_win_64bit(plda);
> > +
> >
> > _______________________________________________
> > linux-riscv mailing list
> > [email protected]
> > http://lists.infradead.org/mailman/listinfo/linux-riscv