Re: [PATCH v3 06/11] PCI: brcmstb: Avoid turn off of bridge reset

Jim Quinlan
2024-10-16T17:18:59Z

On Mon, Oct 14, 2024 at 9:07 AM Stanimir Varbanov <svarbanov@suse.de> wrote:
>
> On PCIe turn off avoid shutdown of bridge reset,
> by introducing a quirk flag.
>
> Signed-off-by: Stanimir Varbanov <svarbanov@suse.de>
> ---
> v2 -> v3:
> - Added more descriptive comment on CFG_QUIRK_AVOID_BRIDGE_SHUTDOWN quirk.
>
> drivers/pci/controller/pcie-brcmstb.c | 17 +++++++++++++++--
> 1 file changed, 15 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c
> index b76c16287f37..757a1646d53c 100644
> --- a/drivers/pci/controller/pcie-brcmstb.c
> +++ b/drivers/pci/controller/pcie-brcmstb.c
> @@ -234,10 +234,20 @@ struct inbound_win {
> u64 cpu_addr;
> };
>
> +/*
> + * The RESCAL block is tied to PCIe controller #1, regardless of the number of
> + * controllers, and turning off PCIe controller #1 prevents access to the RESCAL
> + * register blocks, therefore not other controller can access this register

s/no/not/

I assume that the quirks is specific to 2712 as the 7712 does not need
this since it only has PCIe1
(I'll probably seethis as I read more of your commits).

-- Jim

> + * space, and depending upon the bus fabric we may get a timeout (UBUS/GISB),
> + * or a hang (AXI).
> + */
> +#define CFG_QUIRK_AVOID_BRIDGE_SHUTDOWN BIT(0)
> +
> struct pcie_cfg_data {
> const int *offsets;
> const enum pcie_soc_base soc_base;
> const bool has_phy;
> + const u32 quirks;
> u8 num_inbound_wins;
> int (*perst_set)(struct brcm_pcie *pcie, u32 val);
> int (*bridge_sw_init_set)(struct brcm_pcie *pcie, u32 val);
> @@ -290,6 +300,7 @@ struct brcm_pcie {
> struct subdev_regulators *sr;
> bool ep_wakeup_capable;
> bool has_phy;
> + u32 quirks;
> u8 num_inbound_wins;
> };
>
> @@ -1539,8 +1550,9 @@ static int brcm_pcie_turn_off(struct brcm_pcie *pcie)
> u32p_replace_bits(&tmp, 1, PCIE_MISC_HARD_PCIE_HARD_DEBUG_SERDES_IDDQ_MASK);
> writel(tmp, base + HARD_DEBUG(pcie));
>
> - /* Shutdown PCIe bridge */
> - ret = pcie->bridge_sw_init_set(pcie, 1);
> + if (!(pcie->quirks & CFG_QUIRK_AVOID_BRIDGE_SHUTDOWN))
> + /* Shutdown PCIe bridge */
> + ret = pcie->bridge_sw_init_set(pcie, 1);
>
> return ret;
> }
> @@ -1854,6 +1866,7 @@ static int brcm_pcie_probe(struct platform_device *pdev)
> pcie->perst_set = data->perst_set;
> pcie->bridge_sw_init_set = data->bridge_sw_init_set;
> pcie->has_phy = data->has_phy;
> + pcie->quirks = data->quirks;
> pcie->num_inbound_wins = data->num_inbound_wins;
>
> pcie->base = devm_platform_ioremap_resource(pdev, 0);
> --
> 2.43.0
>