On Fri, Jul 15, 2022 at 05:29:25PM +0530, Krishna chaitanya chundru wrote:
> Allow L1 and its sub-states in the qcom pcie driver.
> By default this is disabled in the qcom specific hardware.
> So enabling it explicitly only for controllers belonging to
> 2_7_0.
>
> This patch will not affect any link capability registers, this
> will allow the link transitions to L1 and its sub states only
> if they are already supported.
>
> Signed-off-by: Krishna chaitanya chundru <quic_krichai@xxxxxxxxxxx>
> Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
Stan, could you please review this patch?
Thanks,
Mani
> ----
>
> Changes since v1 & v2:
> - Update in the commit text only.
> ---
> drivers/pci/controller/dwc/pcie-qcom.c | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
> index a7202f0..5ef444f 100644
> --- a/drivers/pci/controller/dwc/pcie-qcom.c
> +++ b/drivers/pci/controller/dwc/pcie-qcom.c
> @@ -41,6 +41,9 @@
> #define L23_CLK_RMV_DIS BIT(2)
> #define L1_CLK_RMV_DIS BIT(1)
>
> +#define PCIE20_PARF_PM_CTRL 0x20
> +#define REQ_NOT_ENTR_L1 BIT(5)
> +
> #define PCIE20_PARF_PHY_CTRL 0x40
> #define PHY_CTRL_PHY_TX0_TERM_OFFSET_MASK GENMASK(20, 16)
> #define PHY_CTRL_PHY_TX0_TERM_OFFSET(x) ((x) << 16)
> @@ -1261,6 +1264,11 @@ static int qcom_pcie_init_2_7_0(struct qcom_pcie *pcie)
> val |= BIT(4);
> writel(val, pcie->parf + PCIE20_PARF_MHI_CLOCK_RESET_CTRL);
>
> + /* Enable L1 and L1ss */
> + val = readl(pcie->parf + PCIE20_PARF_PM_CTRL);
> + val &= ~REQ_NOT_ENTR_L1;
> + writel(val, pcie->parf + PCIE20_PARF_PM_CTRL);
> +
> if (IS_ENABLED(CONFIG_PCI_MSI)) {
> val = readl(pcie->parf + PCIE20_PARF_AXI_MSTR_WR_ADDR_HALT);
> val |= BIT(31);
> --
> 2.7.4
>
