diff options
Diffstat (limited to 'drivers/pci/controller')
| -rw-r--r-- | drivers/pci/controller/pcie-mediatek-gen3.c | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/drivers/pci/controller/pcie-mediatek-gen3.c b/drivers/pci/controller/pcie-mediatek-gen3.c index 98a2eee75a0a..3c5b97716d40 100644 --- a/drivers/pci/controller/pcie-mediatek-gen3.c +++ b/drivers/pci/controller/pcie-mediatek-gen3.c @@ -45,6 +45,9 @@ #define PCIE_PE_RSTB BIT(3) #define PCIE_LTSSM_STATUS_REG 0x150 +#define PCIE_LTSSM_STATE_MASK GENMASK(28, 24) +#define PCIE_LTSSM_STATE(val) ((val & PCIE_LTSSM_STATE_MASK) >> 24) +#define PCIE_LTSSM_STATE_L2_IDLE 0x14 #define PCIE_LINK_STATUS_REG 0x154 #define PCIE_PORT_LINKUP BIT(8) @@ -73,6 +76,9 @@ #define PCIE_MSI_SET_ADDR_HI_BASE 0xc80 #define PCIE_MSI_SET_ADDR_HI_OFFSET 0x04 +#define PCIE_ICMD_PM_REG 0x198 +#define PCIE_TURN_OFF_LINK BIT(4) + #define PCIE_TRANS_TABLE_BASE_REG 0x800 #define PCIE_ATR_SRC_ADDR_MSB_OFFSET 0x4 #define PCIE_ATR_TRSL_ADDR_LSB_OFFSET 0x8 @@ -95,10 +101,12 @@ * struct mtk_msi_set - MSI information for each set * @base: IO mapped register base * @msg_addr: MSI message address + * @saved_irq_state: IRQ enable state saved at suspend time */ struct mtk_msi_set { void __iomem *base; phys_addr_t msg_addr; + u32 saved_irq_state; }; /** @@ -112,6 +120,7 @@ struct mtk_msi_set { * @clks: PCIe clocks * @num_clks: PCIe clocks count for this port * @irq: PCIe controller interrupt number + * @saved_irq_state: IRQ enable state saved at suspend time * @irq_lock: lock protecting IRQ register access * @intx_domain: legacy INTx IRQ domain * @msi_domain: MSI IRQ domain @@ -131,6 +140,7 @@ struct mtk_pcie_port { int num_clks; int irq; + u32 saved_irq_state; raw_spinlock_t irq_lock; struct irq_domain *intx_domain; struct irq_domain *msi_domain; @@ -896,6 +906,108 @@ static int mtk_pcie_remove(struct platform_device *pdev) return 0; } +static void __maybe_unused mtk_pcie_irq_save(struct mtk_pcie_port *port) +{ + int i; + + raw_spin_lock(&port->irq_lock); + + port->saved_irq_state = readl_relaxed(port->base + PCIE_INT_ENABLE_REG); + + for (i = 0; i < PCIE_MSI_SET_NUM; i++) { + struct mtk_msi_set *msi_set = &port->msi_sets[i]; + + msi_set->saved_irq_state = readl_relaxed(msi_set->base + + PCIE_MSI_SET_ENABLE_OFFSET); + } + + raw_spin_unlock(&port->irq_lock); +} + +static void __maybe_unused mtk_pcie_irq_restore(struct mtk_pcie_port *port) +{ + int i; + + raw_spin_lock(&port->irq_lock); + + writel_relaxed(port->saved_irq_state, port->base + PCIE_INT_ENABLE_REG); + + for (i = 0; i < PCIE_MSI_SET_NUM; i++) { + struct mtk_msi_set *msi_set = &port->msi_sets[i]; + + writel_relaxed(msi_set->saved_irq_state, + msi_set->base + PCIE_MSI_SET_ENABLE_OFFSET); + } + + raw_spin_unlock(&port->irq_lock); +} + +static int __maybe_unused mtk_pcie_turn_off_link(struct mtk_pcie_port *port) +{ + u32 val; + + val = readl_relaxed(port->base + PCIE_ICMD_PM_REG); + val |= PCIE_TURN_OFF_LINK; + writel_relaxed(val, port->base + PCIE_ICMD_PM_REG); + + /* Check the link is L2 */ + return readl_poll_timeout(port->base + PCIE_LTSSM_STATUS_REG, val, + (PCIE_LTSSM_STATE(val) == + PCIE_LTSSM_STATE_L2_IDLE), 20, + 50 * USEC_PER_MSEC); +} + +static int __maybe_unused mtk_pcie_suspend_noirq(struct device *dev) +{ + struct mtk_pcie_port *port = dev_get_drvdata(dev); + int err; + u32 val; + + /* Trigger link to L2 state */ + err = mtk_pcie_turn_off_link(port); + if (err) { + dev_err(port->dev, "cannot enter L2 state\n"); + return err; + } + + /* Pull down the PERST# pin */ + val = readl_relaxed(port->base + PCIE_RST_CTRL_REG); + val |= PCIE_PE_RSTB; + writel_relaxed(val, port->base + PCIE_RST_CTRL_REG); + + dev_dbg(port->dev, "entered L2 states successfully"); + + mtk_pcie_irq_save(port); + mtk_pcie_power_down(port); + + return 0; +} + +static int __maybe_unused mtk_pcie_resume_noirq(struct device *dev) +{ + struct mtk_pcie_port *port = dev_get_drvdata(dev); + int err; + + err = mtk_pcie_power_up(port); + if (err) + return err; + + err = mtk_pcie_startup_port(port); + if (err) { + mtk_pcie_power_down(port); + return err; + } + + mtk_pcie_irq_restore(port); + + return 0; +} + +static const struct dev_pm_ops mtk_pcie_pm_ops = { + SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(mtk_pcie_suspend_noirq, + mtk_pcie_resume_noirq) +}; + static const struct of_device_id mtk_pcie_of_match[] = { { .compatible = "mediatek,mt8192-pcie" }, {}, @@ -907,6 +1019,7 @@ static struct platform_driver mtk_pcie_driver = { .driver = { .name = "mtk-pcie", .of_match_table = mtk_pcie_of_match, + .pm = &mtk_pcie_pm_ops, }, }; |