Re: [PATCH v7 2/3] PCI: rockchip: Simplify reset control handling by using reset_control_bulk*() function

Anand Moon
2024-10-12T07:25:48Z

Hi Manivannan,

Thanks for your review comments.

On Sat, 12 Oct 2024 at 11:48, Manivannan Sadhasivam
<manivannan.sadhasivam@linaro.org> wrote:
>
> On Sat, Oct 12, 2024 at 10:36:04AM +0530, Anand Moon wrote:
> > Refactor the reset control handling in the Rockchip PCIe driver,
> > introducing a more robust and efficient method for assert and
> > deassert reset controller using reset_control_bulk*() API. Using the
> > reset_control_bulk APIs, the reset handling for the core clocks reset
> > unit becomes much simpler.
> >
>
> Same comments as previous patch.
>
I will explain more about this.
> > Spilt the reset controller in two groups as pre the RK3399 TRM.
>
> *per
>
> Also please state the TRM name and section for reference.
>
Yes
> > After power up, the software driver should de-assert the reset of PCIe PHY,
> > then wait the PLL locked by polling the status, if PLL
> > has locked, then can de-assert the reset simultaneously
> > driver need to De-assert the reset pins simultionaly.
> >
> > PIPE_RESET_N/MGMT_STICKY_RESET_N/MGMT_RESET_N/RESET_N.
> >
> > - replace devm_reset_control_get_exclusive() with
> > devm_reset_control_bulk_get_exclusive().
> > - replace reset_control_assert with
> > reset_control_bulk_assert().
> > - replace reset_control_deassert with
> > reset_control_bulk_deassert().
> >
> > Signed-off-by: Anand Moon <linux.amoon@gmail.com>
> > ---
> > v7: replace devm_reset_control_bulk_get_optional_exclusive()
> > with devm_reset_control_bulk_get_exclusive()
> > update the functional changes.
> > V6: Add reason for the split of the RESET pins.
> > v5: Fix the De-assert reset core as per the TRM
> > De-assert the PIPE_RESET_N/MGMT_STICKY_RESET_N/MGMT_RESET_N/RESET_N
> > simultaneously.
> > v4: use dev_err_probe in error path.
> > v3: Fix typo in commit message, dropped reported by.
> > v2: Fix compilation error reported by Intel test robot
> > fixed checkpatch warning.
> > ---
> > drivers/pci/controller/pcie-rockchip.c | 151 +++++--------------------
> > drivers/pci/controller/pcie-rockchip.h | 26 +++--
> > 2 files changed, 49 insertions(+), 128 deletions(-)
> >
> > diff --git a/drivers/pci/controller/pcie-rockchip.c b/drivers/pci/controller/pcie-rockchip.c
> > index 2777ef0cb599..9a118e2b8cbd 100644
> > --- a/drivers/pci/controller/pcie-rockchip.c
> > +++ b/drivers/pci/controller/pcie-rockchip.c
> > @@ -30,7 +30,7 @@ int rockchip_pcie_parse_dt(struct rockchip_pcie *rockchip)
>
> [...]
>
> > + err = reset_control_bulk_assert(ROCKCHIP_NUM_PM_RSTS,
> > + rockchip->pm_rsts);
> > + if (err)
> > + return dev_err_probe(dev, err, "reset bulk assert pm reset\n");
>
> 'Couldn't assert PM resets'
>
> >
> > for (i = 0; i < MAX_LANE_NUM; i++) {
> > err = phy_init(rockchip->phys[i]);
> > @@ -173,47 +128,17 @@ int rockchip_pcie_init_port(struct rockchip_pcie *rockchip)
> > }
> > }
> >
> > - err = reset_control_assert(rockchip->core_rst);
> > - if (err) {
> > - dev_err(dev, "assert core_rst err %d\n", err);
> > - goto err_exit_phy;
> > - }
> > -
> > - err = reset_control_assert(rockchip->mgmt_rst);
> > - if (err) {
> > - dev_err(dev, "assert mgmt_rst err %d\n", err);
> > - goto err_exit_phy;
> > - }
> > -
> > - err = reset_control_assert(rockchip->mgmt_sticky_rst);
> > - if (err) {
> > - dev_err(dev, "assert mgmt_sticky_rst err %d\n", err);
> > - goto err_exit_phy;
> > - }
> > -
> > - err = reset_control_assert(rockchip->pipe_rst);
> > - if (err) {
> > - dev_err(dev, "assert pipe_rst err %d\n", err);
> > - goto err_exit_phy;
> > - }
> > + err = reset_control_bulk_assert(ROCKCHIP_NUM_CORE_RSTS,
> > + rockchip->core_rsts);
> > + if (err)
> > + return dev_err_probe(dev, err, "reset bulk assert core reset\n");
>
> 'Couldn't assert Core resets'
>
> >
> > udelay(10);
> >
> > - err = reset_control_deassert(rockchip->pm_rst);
> > - if (err) {
> > - dev_err(dev, "deassert pm_rst err %d\n", err);
> > - goto err_exit_phy;
> > - }
> > -
> > - err = reset_control_deassert(rockchip->aclk_rst);
> > + err = reset_control_bulk_deassert(ROCKCHIP_NUM_PM_RSTS,
> > + rockchip->pm_rsts);
> > if (err) {
> > - dev_err(dev, "deassert aclk_rst err %d\n", err);
> > - goto err_exit_phy;
> > - }
> > -
> > - err = reset_control_deassert(rockchip->pclk_rst);
> > - if (err) {
> > - dev_err(dev, "deassert pclk_rst err %d\n", err);
> > + dev_err(dev, "reset bulk deassert pm err %d\n", err);
>
> 'Couldn't deassert PM resets'
>
> > goto err_exit_phy;
> > }
> >
> > @@ -256,31 +181,15 @@ int rockchip_pcie_init_port(struct rockchip_pcie *rockchip)
> > * Please don't reorder the deassert sequence of the following
> > * four reset pins.
>
> I don't think my earlier comment on this addressed. Why are you changing the
> reset order? Why can't you have the resets in below (older) order?
>
> static const char * const rockchip_pci_core_rsts[] = {
> mgmt-sticky",
> "core",
> "mgmt",
> "pipe",
> };
I will add a comment on this above.
>
> Also, this comment should be removed now.
>
> > */
> > - err = reset_control_deassert(rockchip->mgmt_sticky_rst);
> > - if (err) {
> > - dev_err(dev, "deassert mgmt_sticky_rst err %d\n", err);
> > - goto err_power_off_phy;
> > - }
> > -
> > - err = reset_control_deassert(rockchip->core_rst);
> > + err = reset_control_bulk_deassert(ROCKCHIP_NUM_CORE_RSTS,
> > + rockchip->core_rsts);
> > if (err) {
> > - dev_err(dev, "deassert core_rst err %d\n", err);
> > - goto err_power_off_phy;
> > - }
> > -
> > - err = reset_control_deassert(rockchip->mgmt_rst);
> > - if (err) {
> > - dev_err(dev, "deassert mgmt_rst err %d\n", err);
> > - goto err_power_off_phy;
> > - }
> > -
> > - err = reset_control_deassert(rockchip->pipe_rst);
> > - if (err) {
> > - dev_err(dev, "deassert pipe_rst err %d\n", err);
> > + dev_err(dev, "reset bulk deassert core err %d\n", err);
>
> 'Couldn't deassert Core resets'
>
> - Mani
>
> --
> மணிவண்ணன் சதாசிவம்

Ok,I will try to improve this in the next version.

Thanks

-Anand