Hi Frank,
On Mi, 2023-12-06 at 10:58 -0500, Frank Li wrote:
> Refactors the reset handling logic in the imx6 PCI driver by adding
> IMX6_PCIE_FLAG_HAS_*_RESET bitmask define for drvdata::flags.
>
> The drvdata::flags and a bitmask ensures a cleaner and more scalable
> switch-case structure for handling reset.
>
> Signed-off-by: Frank Li <Frank.Li@xxxxxxx>
> ---
> drivers/pci/controller/dwc/pci-imx6.c | 115 +++++++++++---------------
> 1 file changed, 47 insertions(+), 68 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
> index bcf52aa86462..62d77fabd82a 100644
> --- a/drivers/pci/controller/dwc/pci-imx6.c
> +++ b/drivers/pci/controller/dwc/pci-imx6.c
[...]
> @@ -696,18 +698,13 @@ static void imx6_pcie_clk_disable(struct imx6_pcie *imx6_pcie)
>
> static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie)
> {
> - switch (imx6_pcie->drvdata->variant) {
> - case IMX7D:
> - case IMX8MQ:
> - case IMX8MQ_EP:
> + if (imx6_check_flag(imx6_pcie, IMX6_PCIE_FLAG_HAS_PHY_RESET))
This check is not strictly necessary. If the flag is not set,
imx6_pcie->pciephy_reset is guaranteed to be NULL, and then
reset_control_assert() is a no-op. Same for the other (de)assert
calls below.
[...]
> @@ -1335,36 +1319,24 @@ static int imx6_pcie_probe(struct platform_device *pdev)
> "failed to get pcie phy\n");
> }
>
> - switch (imx6_pcie->drvdata->variant) {
> - case IMX7D:
> - if (dbi_base->start == IMX8MQ_PCIE2_BASE_ADDR)
> - imx6_pcie->controller_id = 1;
> -
> - imx6_pcie->pciephy_reset = devm_reset_control_get_exclusive(dev,
> - "pciephy");
> - if (IS_ERR(imx6_pcie->pciephy_reset)) {
> - dev_err(dev, "Failed to get PCIEPHY reset control\n");
> - return PTR_ERR(imx6_pcie->pciephy_reset);
> - }
> -
> - imx6_pcie->apps_reset = devm_reset_control_get_exclusive(dev,
> - "apps");
> - if (IS_ERR(imx6_pcie->apps_reset)) {
> - dev_err(dev, "Failed to get PCIE APPS reset control\n");
> - return PTR_ERR(imx6_pcie->apps_reset);
> - }
> - break;
> - case IMX8MM:
> - case IMX8MM_EP:
> - case IMX8MP:
> - case IMX8MP_EP:
> - imx6_pcie->apps_reset = devm_reset_control_get_exclusive(dev,
> - "apps");
> + if (imx6_check_flag(imx6_pcie, IMX6_PCIE_FLAG_HAS_APP_RESET)) {
> + imx6_pcie->apps_reset = devm_reset_control_get_exclusive(dev, "apps");
[...]
I wonder whether we should just defer the check whether apps/pciephy
resets should be used to the device tree validation, and make this an
unconditional call to get an optional reset control:
imx6_pcie->apps_reset = devm_reset_control_get_optional_exclusive(dev, "apps");
regards
Philipp
