On Sun, Nov 26, 2017 at 01:02:12AM +0530, Manikanta Maddireddy wrote:
> Per PCIe r3.0, sec 5.3.3.2.1, PCIe root port shoould 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.
s/PME_turn_Off/PME_Turn_Off/ above to match spec.
I thought PME_TO_Ack was also mis-capitalized, but it's not. Guess
that "TO" stands for "Turn Off".
> Signed-off-by: Manikanta Maddireddy <mmaddireddy@xxxxxxxxxx>
> ---
> V2:
> * no change in this patch
>
> drivers/pci/host/pci-tegra.c | 76 ++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 76 insertions(+)
>
> diff --git a/drivers/pci/host/pci-tegra.c b/drivers/pci/host/pci-tegra.c
> index bbc2807bcd4a..b380958a3deb 100644
> --- a/drivers/pci/host/pci-tegra.c
> +++ b/drivers/pci/host/pci-tegra.c
> @@ -155,6 +155,8 @@
> #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
> @@ -315,6 +317,7 @@
> #define PADS_REFCLK_CFG_DRVI_SHIFT 12 /* 15:12 */
>
> #define LINK_RETRAIN_TIMEOUT 100000
> +#define PME_ACK_TIMEOUT 10000
>
> struct tegra_msi {
> struct msi_controller chip;
> @@ -1503,6 +1506,76 @@ static int tegra_pcie_put_resources(struct tegra_pcie *pcie)
> return 0;
> }
>
> +static inline u32 get_pme_turnoff_bitmap(struct tegra_pcie_port *port)
> +{
> + struct device *dev = port->pcie->dev;
> + struct device_node *np = dev->of_node;
> + int ret = 0;
Unnecessary initialization. In fact, the variable is unnecessary; you
can just return the value directly as soon as you know it.
> +
> + switch (port->index) {
> + case 0:
> + ret = 0;
> + case 1:
> + ret = 8;
> + case 2:
> + if (of_device_is_compatible(np, "nvidia,tegra30-pcie"))
> + ret = 16;
> + else
> + ret = 12;
> + }
> + return ret;
> +}
> +
> +static inline u32 get_pme_ack_bitmap(struct tegra_pcie_port *port)
> +{
> + struct device *dev = port->pcie->dev;
> + struct device_node *np = dev->of_node;
> + int ret = 0;
Similar.
> +
> + switch (port->index) {
> + case 0:
> + ret = 5;
> + case 1:
> + ret = 10;
> + case 2:
> + if (of_device_is_compatible(np, "nvidia,tegra30-pcie"))
> + ret = 18;
> + else
> + ret = 14;
> + }
> + return ret;
> +}
> +
> +static void tegra_pcie_pme_turnoff(struct tegra_pcie_port *port)
> +{
> + struct tegra_pcie *pcie = port->pcie;
> + ktime_t deadline;
> + unsigned int data;
> +
> + data = afi_readl(pcie, AFI_PCIE_PME);
> + data |= (0x1 << get_pme_turnoff_bitmap(port));
> + afi_writel(pcie, data, AFI_PCIE_PME);
> +
> + deadline = ktime_add_us(ktime_get(), PME_ACK_TIMEOUT);
> + do {
> + data = afi_readl(pcie, AFI_PCIE_PME);
> + data &= (0x1 << get_pme_ack_bitmap(port));
> + udelay(1);
> + if (ktime_after(ktime_get(), deadline))
> + break;
> + } while (!data);
> +
> + if (data)
> + dev_err(pcie->dev, "PME Ack is not receieved on port: %d\n",
s/receieved/received/
> + port->index);
> +
> + usleep_range(10000, 11000);
> +
> + data = afi_readl(pcie, AFI_PCIE_PME);
> + data &= ~(0x1 << get_pme_turnoff_bitmap(port));
> + afi_writel(pcie, data, AFI_PCIE_PME);
> +}
> +
> static int tegra_msi_alloc(struct tegra_msi *chip)
> {
> int msi;
> @@ -2828,6 +2901,7 @@ 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, *tmp;
>
> if (IS_ENABLED(CONFIG_DEBUG_FS))
> tegra_pcie_debugfs_exit(pcie);
> @@ -2835,6 +2909,8 @@ static int tegra_pcie_remove(struct platform_device *pdev)
> pci_remove_root_bus(host->bus);
> if (IS_ENABLED(CONFIG_PCI_MSI))
> tegra_pcie_disable_msi(pcie);
> + list_for_each_entry_safe(port, tmp, &pcie->ports, list)
> + tegra_pcie_pme_turnoff(port);
> tegra_pcie_disable_ports(pcie);
> tegra_pcie_free_resources(pcie);
> tegra_pcie_disable_controller(pcie);
> --
> 2.1.4
>
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