Implement remove callback function for Tegra PCIe driver to add loadable kernel module support. Per PCIe r3.0, sec 5.3.3.2.1, PCIe root port should broadcast PME_Turn_Off message before PCIe link goes to L2. PME_Turn_Off broadcast mechanism is implemented in AFI module. Each Tegra PCIe root port has its own PME_Turn_Off and PME_TO_Ack bitmap in AFI_PME register, program this register to broadcast PME_Turn_Off message. Once PME_TO_Ack is recieved driver will turn OFF PCIe clock, power gate PCIe partition and turn OFF regulators. Signed-off-by: Manikanta Maddireddy <mmaddireddy@xxxxxxxxxx> Acked-by: Thierry Reding <treding@xxxxxxxxxx> Tested-by: Thierry Reding <treding@xxxxxxxxxx> --- V2: * no change in this patch V3: * use tegra_pcie_debugfs_exit() helper function in tegra_pcie_debugfs_init() V4: * no change in this patch V5: * Decoupled from https://patchwork.ozlabs.org/patch/832053/ and rebased on linux-next V6: * no change in this patch V7: * no change in this patch V8: * Added new lines around conditional blocks V9: * Squash PME_Turn_Off patch on top this to have single working LKM patch drivers/pci/host/pci-tegra.c | 103 +++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 100 insertions(+), 3 deletions(-) diff --git a/drivers/pci/host/pci-tegra.c b/drivers/pci/host/pci-tegra.c index e68507f658d8..60b1d5e1cfa4 100644 --- a/drivers/pci/host/pci-tegra.c +++ b/drivers/pci/host/pci-tegra.c @@ -31,10 +31,12 @@ #include <linux/delay.h> #include <linux/export.h> #include <linux/interrupt.h> +#include <linux/iopoll.h> #include <linux/irq.h> #include <linux/irqdomain.h> #include <linux/kernel.h> #include <linux/init.h> +#include <linux/module.h> #include <linux/msi.h> #include <linux/of_address.h> #include <linux/of_pci.h> @@ -152,6 +154,8 @@ #define AFI_INTR_EN_FPCI_TIMEOUT (1 << 7) #define AFI_INTR_EN_PRSNT_SENSE (1 << 8) +#define AFI_PCIE_PME 0xf0 + #define AFI_PCIE_CONFIG 0x0f8 #define AFI_PCIE_CONFIG_PCIE_DISABLE(x) (1 << ((x) + 1)) #define AFI_PCIE_CONFIG_PCIE_DISABLE_ALL 0xe @@ -232,6 +236,8 @@ #define PADS_REFCLK_CFG_PREDI_SHIFT 8 /* 11:8 */ #define PADS_REFCLK_CFG_DRVI_SHIFT 12 /* 15:12 */ +#define PME_ACK_TIMEOUT 10000 + struct tegra_msi { struct msi_controller chip; DECLARE_BITMAP(used, INT_PCI_MSI_NR); @@ -243,8 +249,16 @@ struct tegra_msi { }; /* used to differentiate between Tegra SoC generations */ +struct tegra_pcie_port_soc { + struct { + u8 turnoff_bit; + u8 ack_bit; + } pme; +}; + struct tegra_pcie_soc { unsigned int num_ports; + const struct tegra_pcie_port_soc *ports; unsigned int msi_base_shift; u32 pads_pll_ctl; u32 tx_ref_sel; @@ -1357,6 +1371,32 @@ static int tegra_pcie_put_resources(struct tegra_pcie *pcie) return 0; } +static void tegra_pcie_pme_turnoff(struct tegra_pcie_port *port) +{ + struct tegra_pcie *pcie = port->pcie; + const struct tegra_pcie_soc *soc = pcie->soc; + int err; + u32 val; + u8 ack_bit; + + val = afi_readl(pcie, AFI_PCIE_PME); + val |= (0x1 << soc->ports[port->index].pme.turnoff_bit); + afi_writel(pcie, val, AFI_PCIE_PME); + + ack_bit = soc->ports[port->index].pme.ack_bit; + err = readl_poll_timeout(pcie->afi + AFI_PCIE_PME, val, + val & (0x1 << ack_bit), 1, PME_ACK_TIMEOUT); + if (err) + dev_err(pcie->dev, "PME Ack is not received on port: %d\n", + port->index); + + usleep_range(10000, 11000); + + val = afi_readl(pcie, AFI_PCIE_PME); + val &= ~(0x1 << soc->ports[port->index].pme.turnoff_bit); + afi_writel(pcie, val, AFI_PCIE_PME); +} + static int tegra_msi_alloc(struct tegra_msi *chip) { int msi; @@ -2102,8 +2142,14 @@ static void tegra_pcie_disable_ports(struct tegra_pcie *pcie) } } +static const struct tegra_pcie_port_soc tegra20_pcie_ports[] = { + { .pme.turnoff_bit = 0, .pme.ack_bit = 5 }, + { .pme.turnoff_bit = 8, .pme.ack_bit = 10 }, +}; + static const struct tegra_pcie_soc tegra20_pcie = { .num_ports = 2, + .ports = tegra20_pcie_ports, .msi_base_shift = 0, .pads_pll_ctl = PADS_PLL_CTL_TEGRA20, .tx_ref_sel = PADS_PLL_CTL_TXCLKREF_DIV10, @@ -2117,8 +2163,15 @@ static const struct tegra_pcie_soc tegra20_pcie = { .program_uphy = true, }; +static const struct tegra_pcie_port_soc tegra30_pcie_ports[] = { + { .pme.turnoff_bit = 0, .pme.ack_bit = 5 }, + { .pme.turnoff_bit = 8, .pme.ack_bit = 10 }, + { .pme.turnoff_bit = 16, .pme.ack_bit = 18 }, +}; + static const struct tegra_pcie_soc tegra30_pcie = { .num_ports = 3, + .ports = tegra30_pcie_ports, .msi_base_shift = 8, .pads_pll_ctl = PADS_PLL_CTL_TEGRA30, .tx_ref_sel = PADS_PLL_CTL_TXCLKREF_BUF_EN, @@ -2135,6 +2188,7 @@ static const struct tegra_pcie_soc tegra30_pcie = { static const struct tegra_pcie_soc tegra124_pcie = { .num_ports = 2, + .ports = tegra20_pcie_ports, .msi_base_shift = 8, .pads_pll_ctl = PADS_PLL_CTL_TEGRA30, .tx_ref_sel = PADS_PLL_CTL_TXCLKREF_BUF_EN, @@ -2150,6 +2204,7 @@ static const struct tegra_pcie_soc tegra124_pcie = { static const struct tegra_pcie_soc tegra210_pcie = { .num_ports = 2, + .ports = tegra20_pcie_ports, .msi_base_shift = 8, .pads_pll_ctl = PADS_PLL_CTL_TEGRA30, .tx_ref_sel = PADS_PLL_CTL_TXCLKREF_BUF_EN, @@ -2163,8 +2218,15 @@ static const struct tegra_pcie_soc tegra210_pcie = { .program_uphy = true, }; +static const struct tegra_pcie_port_soc tegra186_pcie_ports[] = { + { .pme.turnoff_bit = 0, .pme.ack_bit = 5 }, + { .pme.turnoff_bit = 8, .pme.ack_bit = 10 }, + { .pme.turnoff_bit = 12, .pme.ack_bit = 14 }, +}; + static const struct tegra_pcie_soc tegra186_pcie = { .num_ports = 3, + .ports = tegra186_pcie_ports, .msi_base_shift = 8, .pads_pll_ctl = PADS_PLL_CTL_TEGRA30, .tx_ref_sel = PADS_PLL_CTL_TXCLKREF_BUF_EN, @@ -2276,6 +2338,12 @@ static const struct file_operations tegra_pcie_ports_ops = { .release = seq_release, }; +static void tegra_pcie_debugfs_exit(struct tegra_pcie *pcie) +{ + debugfs_remove_recursive(pcie->debugfs); + pcie->debugfs = NULL; +} + static int tegra_pcie_debugfs_init(struct tegra_pcie *pcie) { struct dentry *file; @@ -2292,8 +2360,7 @@ static int tegra_pcie_debugfs_init(struct tegra_pcie *pcie) return 0; remove: - debugfs_remove_recursive(pcie->debugfs); - pcie->debugfs = NULL; + tegra_pcie_debugfs_exit(pcie); return -ENOMEM; } @@ -2311,6 +2378,7 @@ static int tegra_pcie_probe(struct platform_device *pdev) pcie = pci_host_bridge_priv(host); host->sysdata = pcie; + platform_set_drvdata(pdev, pcie); pcie->soc = of_device_get_match_data(dev); INIT_LIST_HEAD(&pcie->ports); @@ -2388,6 +2456,33 @@ static int tegra_pcie_probe(struct platform_device *pdev) return err; } +static int tegra_pcie_remove(struct platform_device *pdev) +{ + struct tegra_pcie *pcie = platform_get_drvdata(pdev); + struct pci_host_bridge *host = pci_host_bridge_from_priv(pcie); + struct tegra_pcie_port *port; + + if (IS_ENABLED(CONFIG_DEBUG_FS)) + tegra_pcie_debugfs_exit(pcie); + + pci_stop_root_bus(host->bus); + pci_remove_root_bus(host->bus); + + list_for_each_entry(port, &pcie->ports, list) + tegra_pcie_pme_turnoff(port); + + tegra_pcie_disable_ports(pcie); + + if (IS_ENABLED(CONFIG_PCI_MSI)) + tegra_pcie_disable_msi(pcie); + + tegra_pcie_free_resources(pcie); + tegra_pcie_disable_controller(pcie); + tegra_pcie_put_resources(pcie); + + return 0; +} + static struct platform_driver tegra_pcie_driver = { .driver = { .name = "tegra-pcie", @@ -2395,5 +2490,7 @@ static struct platform_driver tegra_pcie_driver = { .suppress_bind_attrs = true, }, .probe = tegra_pcie_probe, + .remove = tegra_pcie_remove, }; -builtin_platform_driver(tegra_pcie_driver); +module_platform_driver(tegra_pcie_driver); +MODULE_LICENSE("GPL"); -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
