From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:49:45 +0200 Subject: Adding upstream version 6.1.76. Signed-off-by: Daniel Baumann --- drivers/pci/controller/dwc/pci-meson.c | 492 +++++++++++++++++++++++++++++++++ 1 file changed, 492 insertions(+) create mode 100644 drivers/pci/controller/dwc/pci-meson.c (limited to 'drivers/pci/controller/dwc/pci-meson.c') diff --git a/drivers/pci/controller/dwc/pci-meson.c b/drivers/pci/controller/dwc/pci-meson.c new file mode 100644 index 000000000..c1527693b --- /dev/null +++ b/drivers/pci/controller/dwc/pci-meson.c @@ -0,0 +1,492 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * PCIe host controller driver for Amlogic MESON SoCs + * + * Copyright (c) 2018 Amlogic, inc. + * Author: Yue Wang + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "pcie-designware.h" + +#define to_meson_pcie(x) dev_get_drvdata((x)->dev) + +#define PCIE_CAP_MAX_PAYLOAD_SIZE(x) ((x) << 5) +#define PCIE_CAP_MAX_READ_REQ_SIZE(x) ((x) << 12) + +/* PCIe specific config registers */ +#define PCIE_CFG0 0x0 +#define APP_LTSSM_ENABLE BIT(7) + +#define PCIE_CFG_STATUS12 0x30 +#define IS_SMLH_LINK_UP(x) ((x) & (1 << 6)) +#define IS_RDLH_LINK_UP(x) ((x) & (1 << 16)) +#define IS_LTSSM_UP(x) ((((x) >> 10) & 0x1f) == 0x11) + +#define PCIE_CFG_STATUS17 0x44 +#define PM_CURRENT_STATE(x) (((x) >> 7) & 0x1) + +#define WAIT_LINKUP_TIMEOUT 4000 +#define PORT_CLK_RATE 100000000UL +#define MAX_PAYLOAD_SIZE 256 +#define MAX_READ_REQ_SIZE 256 +#define PCIE_RESET_DELAY 500 +#define PCIE_SHARED_RESET 1 +#define PCIE_NORMAL_RESET 0 + +enum pcie_data_rate { + PCIE_GEN1, + PCIE_GEN2, + PCIE_GEN3, + PCIE_GEN4 +}; + +struct meson_pcie_clk_res { + struct clk *clk; + struct clk *port_clk; + struct clk *general_clk; +}; + +struct meson_pcie_rc_reset { + struct reset_control *port; + struct reset_control *apb; +}; + +struct meson_pcie { + struct dw_pcie pci; + void __iomem *cfg_base; + struct meson_pcie_clk_res clk_res; + struct meson_pcie_rc_reset mrst; + struct gpio_desc *reset_gpio; + struct phy *phy; +}; + +static struct reset_control *meson_pcie_get_reset(struct meson_pcie *mp, + const char *id, + u32 reset_type) +{ + struct device *dev = mp->pci.dev; + struct reset_control *reset; + + if (reset_type == PCIE_SHARED_RESET) + reset = devm_reset_control_get_shared(dev, id); + else + reset = devm_reset_control_get(dev, id); + + return reset; +} + +static int meson_pcie_get_resets(struct meson_pcie *mp) +{ + struct meson_pcie_rc_reset *mrst = &mp->mrst; + + mrst->port = meson_pcie_get_reset(mp, "port", PCIE_NORMAL_RESET); + if (IS_ERR(mrst->port)) + return PTR_ERR(mrst->port); + reset_control_deassert(mrst->port); + + mrst->apb = meson_pcie_get_reset(mp, "apb", PCIE_SHARED_RESET); + if (IS_ERR(mrst->apb)) + return PTR_ERR(mrst->apb); + reset_control_deassert(mrst->apb); + + return 0; +} + +static int meson_pcie_get_mems(struct platform_device *pdev, + struct meson_pcie *mp) +{ + struct dw_pcie *pci = &mp->pci; + + pci->dbi_base = devm_platform_ioremap_resource_byname(pdev, "elbi"); + if (IS_ERR(pci->dbi_base)) + return PTR_ERR(pci->dbi_base); + + mp->cfg_base = devm_platform_ioremap_resource_byname(pdev, "cfg"); + if (IS_ERR(mp->cfg_base)) + return PTR_ERR(mp->cfg_base); + + return 0; +} + +static int meson_pcie_power_on(struct meson_pcie *mp) +{ + int ret = 0; + + ret = phy_init(mp->phy); + if (ret) + return ret; + + ret = phy_power_on(mp->phy); + if (ret) { + phy_exit(mp->phy); + return ret; + } + + return 0; +} + +static void meson_pcie_power_off(struct meson_pcie *mp) +{ + phy_power_off(mp->phy); + phy_exit(mp->phy); +} + +static int meson_pcie_reset(struct meson_pcie *mp) +{ + struct meson_pcie_rc_reset *mrst = &mp->mrst; + int ret = 0; + + ret = phy_reset(mp->phy); + if (ret) + return ret; + + reset_control_assert(mrst->port); + reset_control_assert(mrst->apb); + udelay(PCIE_RESET_DELAY); + reset_control_deassert(mrst->port); + reset_control_deassert(mrst->apb); + udelay(PCIE_RESET_DELAY); + + return 0; +} + +static inline struct clk *meson_pcie_probe_clock(struct device *dev, + const char *id, u64 rate) +{ + struct clk *clk; + int ret; + + clk = devm_clk_get(dev, id); + if (IS_ERR(clk)) + return clk; + + if (rate) { + ret = clk_set_rate(clk, rate); + if (ret) { + dev_err(dev, "set clk rate failed, ret = %d\n", ret); + return ERR_PTR(ret); + } + } + + ret = clk_prepare_enable(clk); + if (ret) { + dev_err(dev, "couldn't enable clk\n"); + return ERR_PTR(ret); + } + + devm_add_action_or_reset(dev, + (void (*) (void *))clk_disable_unprepare, + clk); + + return clk; +} + +static int meson_pcie_probe_clocks(struct meson_pcie *mp) +{ + struct device *dev = mp->pci.dev; + struct meson_pcie_clk_res *res = &mp->clk_res; + + res->port_clk = meson_pcie_probe_clock(dev, "port", PORT_CLK_RATE); + if (IS_ERR(res->port_clk)) + return PTR_ERR(res->port_clk); + + res->general_clk = meson_pcie_probe_clock(dev, "general", 0); + if (IS_ERR(res->general_clk)) + return PTR_ERR(res->general_clk); + + res->clk = meson_pcie_probe_clock(dev, "pclk", 0); + if (IS_ERR(res->clk)) + return PTR_ERR(res->clk); + + return 0; +} + +static inline u32 meson_cfg_readl(struct meson_pcie *mp, u32 reg) +{ + return readl(mp->cfg_base + reg); +} + +static inline void meson_cfg_writel(struct meson_pcie *mp, u32 val, u32 reg) +{ + writel(val, mp->cfg_base + reg); +} + +static void meson_pcie_assert_reset(struct meson_pcie *mp) +{ + gpiod_set_value_cansleep(mp->reset_gpio, 1); + udelay(500); + gpiod_set_value_cansleep(mp->reset_gpio, 0); +} + +static void meson_pcie_ltssm_enable(struct meson_pcie *mp) +{ + u32 val; + + val = meson_cfg_readl(mp, PCIE_CFG0); + val |= APP_LTSSM_ENABLE; + meson_cfg_writel(mp, val, PCIE_CFG0); +} + +static int meson_size_to_payload(struct meson_pcie *mp, int size) +{ + struct device *dev = mp->pci.dev; + + /* + * dwc supports 2^(val+7) payload size, which val is 0~5 default to 1. + * So if input size is not 2^order alignment or less than 2^7 or bigger + * than 2^12, just set to default size 2^(1+7). + */ + if (!is_power_of_2(size) || size < 128 || size > 4096) { + dev_warn(dev, "payload size %d, set to default 256\n", size); + return 1; + } + + return fls(size) - 8; +} + +static void meson_set_max_payload(struct meson_pcie *mp, int size) +{ + struct dw_pcie *pci = &mp->pci; + u32 val; + u16 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP); + int max_payload_size = meson_size_to_payload(mp, size); + + val = dw_pcie_readl_dbi(pci, offset + PCI_EXP_DEVCTL); + val &= ~PCI_EXP_DEVCTL_PAYLOAD; + dw_pcie_writel_dbi(pci, offset + PCI_EXP_DEVCTL, val); + + val = dw_pcie_readl_dbi(pci, offset + PCI_EXP_DEVCTL); + val |= PCIE_CAP_MAX_PAYLOAD_SIZE(max_payload_size); + dw_pcie_writel_dbi(pci, offset + PCI_EXP_DEVCTL, val); +} + +static void meson_set_max_rd_req_size(struct meson_pcie *mp, int size) +{ + struct dw_pcie *pci = &mp->pci; + u32 val; + u16 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP); + int max_rd_req_size = meson_size_to_payload(mp, size); + + val = dw_pcie_readl_dbi(pci, offset + PCI_EXP_DEVCTL); + val &= ~PCI_EXP_DEVCTL_READRQ; + dw_pcie_writel_dbi(pci, offset + PCI_EXP_DEVCTL, val); + + val = dw_pcie_readl_dbi(pci, offset + PCI_EXP_DEVCTL); + val |= PCIE_CAP_MAX_READ_REQ_SIZE(max_rd_req_size); + dw_pcie_writel_dbi(pci, offset + PCI_EXP_DEVCTL, val); +} + +static int meson_pcie_start_link(struct dw_pcie *pci) +{ + struct meson_pcie *mp = to_meson_pcie(pci); + + meson_pcie_ltssm_enable(mp); + meson_pcie_assert_reset(mp); + + return 0; +} + +static int meson_pcie_rd_own_conf(struct pci_bus *bus, u32 devfn, + int where, int size, u32 *val) +{ + int ret; + + ret = pci_generic_config_read(bus, devfn, where, size, val); + if (ret != PCIBIOS_SUCCESSFUL) + return ret; + + /* + * There is a bug in the MESON AXG PCIe controller whereby software + * cannot program the PCI_CLASS_DEVICE register, so we must fabricate + * the return value in the config accessors. + */ + if ((where & ~3) == PCI_CLASS_REVISION) { + if (size <= 2) + *val = (*val & ((1 << (size * 8)) - 1)) << (8 * (where & 3)); + *val &= ~0xffffff00; + *val |= PCI_CLASS_BRIDGE_PCI_NORMAL << 8; + if (size <= 2) + *val = (*val >> (8 * (where & 3))) & ((1 << (size * 8)) - 1); + } + + return PCIBIOS_SUCCESSFUL; +} + +static struct pci_ops meson_pci_ops = { + .map_bus = dw_pcie_own_conf_map_bus, + .read = meson_pcie_rd_own_conf, + .write = pci_generic_config_write, +}; + +static int meson_pcie_link_up(struct dw_pcie *pci) +{ + struct meson_pcie *mp = to_meson_pcie(pci); + struct device *dev = pci->dev; + u32 speed_okay = 0; + u32 cnt = 0; + u32 state12, state17, smlh_up, ltssm_up, rdlh_up; + + do { + state12 = meson_cfg_readl(mp, PCIE_CFG_STATUS12); + state17 = meson_cfg_readl(mp, PCIE_CFG_STATUS17); + smlh_up = IS_SMLH_LINK_UP(state12); + rdlh_up = IS_RDLH_LINK_UP(state12); + ltssm_up = IS_LTSSM_UP(state12); + + if (PM_CURRENT_STATE(state17) < PCIE_GEN3) + speed_okay = 1; + + if (smlh_up) + dev_dbg(dev, "smlh_link_up is on\n"); + if (rdlh_up) + dev_dbg(dev, "rdlh_link_up is on\n"); + if (ltssm_up) + dev_dbg(dev, "ltssm_up is on\n"); + if (speed_okay) + dev_dbg(dev, "speed_okay\n"); + + if (smlh_up && rdlh_up && ltssm_up && speed_okay) + return 1; + + cnt++; + + udelay(10); + } while (cnt < WAIT_LINKUP_TIMEOUT); + + dev_err(dev, "error: wait linkup timeout\n"); + return 0; +} + +static int meson_pcie_host_init(struct dw_pcie_rp *pp) +{ + struct dw_pcie *pci = to_dw_pcie_from_pp(pp); + struct meson_pcie *mp = to_meson_pcie(pci); + + pp->bridge->ops = &meson_pci_ops; + + meson_set_max_payload(mp, MAX_PAYLOAD_SIZE); + meson_set_max_rd_req_size(mp, MAX_READ_REQ_SIZE); + + return 0; +} + +static const struct dw_pcie_host_ops meson_pcie_host_ops = { + .host_init = meson_pcie_host_init, +}; + +static const struct dw_pcie_ops dw_pcie_ops = { + .link_up = meson_pcie_link_up, + .start_link = meson_pcie_start_link, +}; + +static int meson_pcie_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct dw_pcie *pci; + struct meson_pcie *mp; + int ret; + + mp = devm_kzalloc(dev, sizeof(*mp), GFP_KERNEL); + if (!mp) + return -ENOMEM; + + pci = &mp->pci; + pci->dev = dev; + pci->ops = &dw_pcie_ops; + pci->pp.ops = &meson_pcie_host_ops; + pci->num_lanes = 1; + + mp->phy = devm_phy_get(dev, "pcie"); + if (IS_ERR(mp->phy)) { + dev_err(dev, "get phy failed, %ld\n", PTR_ERR(mp->phy)); + return PTR_ERR(mp->phy); + } + + mp->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW); + if (IS_ERR(mp->reset_gpio)) { + dev_err(dev, "get reset gpio failed\n"); + return PTR_ERR(mp->reset_gpio); + } + + ret = meson_pcie_get_resets(mp); + if (ret) { + dev_err(dev, "get reset resource failed, %d\n", ret); + return ret; + } + + ret = meson_pcie_get_mems(pdev, mp); + if (ret) { + dev_err(dev, "get memory resource failed, %d\n", ret); + return ret; + } + + ret = meson_pcie_power_on(mp); + if (ret) { + dev_err(dev, "phy power on failed, %d\n", ret); + return ret; + } + + ret = meson_pcie_reset(mp); + if (ret) { + dev_err(dev, "reset failed, %d\n", ret); + goto err_phy; + } + + ret = meson_pcie_probe_clocks(mp); + if (ret) { + dev_err(dev, "init clock resources failed, %d\n", ret); + goto err_phy; + } + + platform_set_drvdata(pdev, mp); + + ret = dw_pcie_host_init(&pci->pp); + if (ret < 0) { + dev_err(dev, "Add PCIe port failed, %d\n", ret); + goto err_phy; + } + + return 0; + +err_phy: + meson_pcie_power_off(mp); + return ret; +} + +static const struct of_device_id meson_pcie_of_match[] = { + { + .compatible = "amlogic,axg-pcie", + }, + { + .compatible = "amlogic,g12a-pcie", + }, + {}, +}; +MODULE_DEVICE_TABLE(of, meson_pcie_of_match); + +static struct platform_driver meson_pcie_driver = { + .probe = meson_pcie_probe, + .driver = { + .name = "meson-pcie", + .of_match_table = meson_pcie_of_match, + }, +}; + +module_platform_driver(meson_pcie_driver); + +MODULE_AUTHOR("Yue Wang "); +MODULE_DESCRIPTION("Amlogic PCIe Controller driver"); +MODULE_LICENSE("GPL v2"); -- cgit v1.2.3