On Tue, Jun 21, 2022 at 01:23:30PM +0200, Robert Marko wrote:
> IPQ8074 has one Gen2 and one Gen3 port, currently the Gen2 port will
> cause the system to hang as its using DBI registers in the .init
> and those are only accesible after phy_power_on().
Is the fact that IPQ8074 has both a Gen2 and a Gen3 port relevant to
this patch? I don't see the connection.
I see that qcom_pcie_host_init() does:
qcom_pcie_host_init
pcie->cfg->ops->init(pcie)
phy_power_on(pcie->phy)
pcie->cfg->ops->post_init(pcie)
and that you're moving DBI register accesses from
qcom_pcie_init_2_3_3() to qcom_pcie_post_init_2_3_3().
But I also see DBI register accesses in other .init() functions:
qcom_pcie_init_2_1_0
qcom_pcie_init_1_0_0 (oddly out of order)
qcom_pcie_init_2_3_2
qcom_pcie_init_2_4_0
Why do these accesses not need to be moved? I assume it's because
pcie->phy is an optional PHY and phy_power_on() does nothing on those
controllers?
Whatever the reason, I think the DBI accesses should be done
consistently in .post_init(). I see that Dmitry's previous patches
removed all those .post_init() functions, but I think the consistency
is worth having.
Perhaps we could reorder the patches so this patch comes first, moves
the DBI accesses into .post_init(), then Dmitry's patches could be
rebased on top to drop the clock handling?
> So solve this by splitting the DBI read/writes to .post_init.
>
> Fixes: a0fd361db8e5 ("PCI: dwc: Move "dbi", "dbi2", and "addr_space" resource setup into common code")
> Signed-off-by: Robert Marko <robimarko@xxxxxxxxx>
> ---
> Changes in v2:
> * Rebase onto next-20220621
> ---
> drivers/pci/controller/dwc/pcie-qcom.c | 48 +++++++++++++++-----------
> 1 file changed, 28 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
> index 51fed83484af..da6d79d61397 100644
> --- a/drivers/pci/controller/dwc/pcie-qcom.c
> +++ b/drivers/pci/controller/dwc/pcie-qcom.c
> @@ -1061,9 +1061,7 @@ static int qcom_pcie_init_2_3_3(struct qcom_pcie *pcie)
> struct qcom_pcie_resources_2_3_3 *res = &pcie->res.v2_3_3;
> struct dw_pcie *pci = pcie->pci;
> struct device *dev = pci->dev;
> - u16 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
> int i, ret;
> - u32 val;
>
> for (i = 0; i < ARRAY_SIZE(res->rst); i++) {
> ret = reset_control_assert(res->rst[i]);
> @@ -1120,6 +1118,33 @@ static int qcom_pcie_init_2_3_3(struct qcom_pcie *pcie)
> goto err_clk_aux;
> }
>
> + return 0;
> +
> +err_clk_aux:
> + clk_disable_unprepare(res->ahb_clk);
> +err_clk_ahb:
> + clk_disable_unprepare(res->axi_s_clk);
> +err_clk_axi_s:
> + clk_disable_unprepare(res->axi_m_clk);
> +err_clk_axi_m:
> + clk_disable_unprepare(res->iface);
> +err_clk_iface:
> + /*
> + * Not checking for failure, will anyway return
> + * the original failure in 'ret'.
> + */
> + for (i = 0; i < ARRAY_SIZE(res->rst); i++)
> + reset_control_assert(res->rst[i]);
> +
> + return ret;
> +}
> +
> +static int qcom_pcie_post_init_2_3_3(struct qcom_pcie *pcie)
> +{
> + struct dw_pcie *pci = pcie->pci;
> + u16 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
> + u32 val;
> +
> writel(SLV_ADDR_SPACE_SZ,
> pcie->parf + PCIE20_v3_PARF_SLV_ADDR_SPACE_SIZE);
>
> @@ -1147,24 +1172,6 @@ static int qcom_pcie_init_2_3_3(struct qcom_pcie *pcie)
> PCI_EXP_DEVCTL2);
>
> return 0;
> -
> -err_clk_aux:
> - clk_disable_unprepare(res->ahb_clk);
> -err_clk_ahb:
> - clk_disable_unprepare(res->axi_s_clk);
> -err_clk_axi_s:
> - clk_disable_unprepare(res->axi_m_clk);
> -err_clk_axi_m:
> - clk_disable_unprepare(res->iface);
> -err_clk_iface:
> - /*
> - * Not checking for failure, will anyway return
> - * the original failure in 'ret'.
> - */
> - for (i = 0; i < ARRAY_SIZE(res->rst); i++)
> - reset_control_assert(res->rst[i]);
> -
> - return ret;
> }
>
> static int qcom_pcie_get_resources_2_7_0(struct qcom_pcie *pcie)
> @@ -1598,6 +1605,7 @@ static const struct qcom_pcie_ops ops_2_4_0 = {
> static const struct qcom_pcie_ops ops_2_3_3 = {
> .get_resources = qcom_pcie_get_resources_2_3_3,
> .init = qcom_pcie_init_2_3_3,
> + .post_init = qcom_pcie_post_init_2_3_3,
> .deinit = qcom_pcie_deinit_2_3_3,
> .ltssm_enable = qcom_pcie_2_3_2_ltssm_enable,
> };
> --
> 2.36.1
>
