| Message ID | 20240910151845.17308-8-svarbanov@suse.de (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Add PCIe support for bcm2712 | expand |
On 9/10/24 08:18, Stanimir Varbanov wrote: > On brcm_pcie_turn_off avoid shutdown of bridge reset. > > Signed-off-by: Stanimir Varbanov <svarbanov@suse.de> > --- > drivers/pci/controller/pcie-brcmstb.c | 14 ++++++++++++-- > 1 file changed, 12 insertions(+), 2 deletions(-) > > diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c > index d78f33b33884..185ccf7fe86a 100644 > --- a/drivers/pci/controller/pcie-brcmstb.c > +++ b/drivers/pci/controller/pcie-brcmstb.c > @@ -234,10 +234,17 @@ struct inbound_win { > u64 cpu_addr; > }; > > +/* > + * Shutting down this bridge on pcie1 means accesses to rescal block > + * will hang the chip if another RC wants to assert/deassert rescal. > + */ Maybe a slightly more detailed comment saying that 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 space, and depending upon the bus fabric we may get a timeout (UBUS/GISB), or a hang (AXI). Thanks!
On 9/10/24 20:03, Florian Fainelli wrote: > On 9/10/24 08:18, Stanimir Varbanov wrote: >> On brcm_pcie_turn_off avoid shutdown of bridge reset. >> >> Signed-off-by: Stanimir Varbanov <svarbanov@suse.de> >> --- >> drivers/pci/controller/pcie-brcmstb.c | 14 ++++++++++++-- >> 1 file changed, 12 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/pci/controller/pcie-brcmstb.c >> b/drivers/pci/controller/pcie-brcmstb.c >> index d78f33b33884..185ccf7fe86a 100644 >> --- a/drivers/pci/controller/pcie-brcmstb.c >> +++ b/drivers/pci/controller/pcie-brcmstb.c >> @@ -234,10 +234,17 @@ struct inbound_win { >> u64 cpu_addr; >> }; >> +/* >> + * Shutting down this bridge on pcie1 means accesses to rescal block >> + * will hang the chip if another RC wants to assert/deassert rescal. >> + */ > > Maybe a slightly more detailed comment saying that 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 space, > and depending upon the bus fabric we may get a timeout (UBUS/GISB), or a > hang (AXI). Ack. Thank you! regards, ~Stan
diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c index d78f33b33884..185ccf7fe86a 100644 --- a/drivers/pci/controller/pcie-brcmstb.c +++ b/drivers/pci/controller/pcie-brcmstb.c @@ -234,10 +234,17 @@ struct inbound_win { u64 cpu_addr; }; +/* + * Shutting down this bridge on pcie1 means accesses to rescal block + * will hang the chip if another RC wants to assert/deassert rescal. + */ +#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 +297,7 @@ struct brcm_pcie { struct subdev_regulators *sr; bool ep_wakeup_capable; bool has_phy; + u32 quirks; u8 num_inbound_wins; }; @@ -1549,8 +1557,9 @@ 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; } @@ -1864,6 +1873,7 @@ 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);
On brcm_pcie_turn_off avoid shutdown of bridge reset. Signed-off-by: Stanimir Varbanov <svarbanov@suse.de> --- drivers/pci/controller/pcie-brcmstb.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-)