On Tue, Feb 13, 2018 at 08:54:09PM +0530, Manikanta Maddireddy wrote:
> Per PCIe r3.0, sec 5.3.3.2.1, PCIe root port shoould broadcast PME_Turn_Off
s/shoould/should
> 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.
>
> 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:
> * add PME bitmap in soc data instead of using compatible string
> * replace while loop with readl_poll_timeout() for polling
> * commit log correction
> V4:
> * no change in this patch
> V5:
> * Rebased on linux-next
> V6:
> * no change in this patch
> V7:
> * Per port soc data is added for pme bits
> * list_for_each_entry_safe is changed to list_for_each_entry for pme turnoff
> V8:
> * Rebased on top of latest patch-2
>
> drivers/pci/host/pci-tegra.c | 66 ++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 66 insertions(+)
>
> diff --git a/drivers/pci/host/pci-tegra.c b/drivers/pci/host/pci-tegra.c
> index 17ccb5e3ba04..60b1d5e1cfa4 100644
> --- a/drivers/pci/host/pci-tegra.c
> +++ b/drivers/pci/host/pci-tegra.c
> @@ -31,6 +31,7 @@
> #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>
> @@ -153,6 +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
> @@ -233,6 +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);
> @@ -244,8 +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;
> @@ -1358,6 +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;
> @@ -2103,8 +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,
> @@ -2118,8 +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,
> @@ -2136,6 +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,
> @@ -2151,6 +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,
> @@ -2164,8 +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,
> @@ -2399,12 +2460,17 @@ 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);
> +
IIUC how it works this patch and the previous one should be swapped,
otherwise the driver removal may not work correctly.
It is just for my own understanding (and bisection reasons).
Thanks,
Lorenzo
> tegra_pcie_disable_ports(pcie);
>
> if (IS_ENABLED(CONFIG_PCI_MSI))
> --
> 2.1.4
>
