Re: [PATCH v2] PCI: controller: convert to devm_platform_ioremap_resource_byname()

From: dann frazier
Date: Sat Mar 27 2021 - 14:03:57 EST

On Wed, Jun 03, 2020 at 01:16:01AM +0800, Dejin Zheng wrote:
> Use devm_platform_ioremap_resource_byname() to simplify codes.
> it contains platform_get_resource_byname() and devm_ioremap_resource().
>
> Signed-off-by: Dejin Zheng <zhengdejin5@xxxxxxxxx>
> ---
> v1 -> v2:
> - Discard changes to the file drivers/pci/controller/pcie-xilinx-nwl.c
> Due to my mistakes, my patch will modify pcie-xilinx-nwl.c,
> but it still need to use the res variable, but
> devm_platform_ioremap_resource_byname() funtion can't assign a
> value to the variable res. kbuild test robot report it. Thanks
> very much for kbuild test robot <lkp@xxxxxxxxx>.
>
> drivers/pci/controller/cadence/pcie-cadence-ep.c | 3 +--
> drivers/pci/controller/cadence/pcie-cadence-host.c | 3 +--
> drivers/pci/controller/pci-tegra.c | 8 +++-----
> drivers/pci/controller/pci-xgene.c | 3 +--
> drivers/pci/controller/pcie-altera-msi.c | 3 +--
> drivers/pci/controller/pcie-altera.c | 9 +++------
> drivers/pci/controller/pcie-mediatek.c | 4 +---
> drivers/pci/controller/pcie-rockchip.c | 5 ++---
> 8 files changed, 13 insertions(+), 25 deletions(-)
>

hey,
I found that recent kernels fail to initialize PCI devices on our HP
m400 Moonshot cartridges, which are based on the X-Gene SoC. I
bisected the issue down to this commit. I found that just reverting
this hunk in pci-xgene.c is enough to get v5.12 rcs booting again:

> diff --git a/drivers/pci/controller/pci-xgene.c b/drivers/pci/controller/pci-xgene.c
> index d1efa8ffbae1..1431a18eb02c 100644
> --- a/drivers/pci/controller/pci-xgene.c
> +++ b/drivers/pci/controller/pci-xgene.c
> @@ -355,8 +355,7 @@ static int xgene_pcie_map_reg(struct xgene_pcie_port *port,
> if (IS_ERR(port->csr_base))
> return PTR_ERR(port->csr_base);
>
> - res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg");
> - port->cfg_base = devm_ioremap_resource(dev, res);
> + port->cfg_base = devm_platform_ioremap_resource_byname(pdev, "cfg");
> if (IS_ERR(port->cfg_base))
> return PTR_ERR(port->cfg_base);
> port->cfg_addr = res->start;


In case it helps, here's the PCI initialization portion of dmesg when
it fails:

[ 0.756359] xgene-pcie 1f500000.pcie: host bridge /soc/pcie@1f500000 ranges:
[ 0.756372] xgene-pcie 1f500000.pcie: No bus range found for /soc/pcie@1f500000, using [bus 00-ff]
[ 0.756387] xgene-pcie 1f500000.pcie: MEM 0xa130000000..0xa1afffffff -> 0x0030000000
[ 0.756404] xgene-pcie 1f500000.pcie: IB MEM 0x4000000000..0x7fffffffff -> 0x4000000000
[ 0.756459] xgene-pcie 1f500000.pcie: (rc) x8 gen-2 link up
[ 0.756525] xgene-pcie 1f500000.pcie: PCI host bridge to bus 0000:00
[ 0.756532] pci_bus 0000:00: root bus resource [bus 00-ff]
[ 0.756538] pci_bus 0000:00: root bus resource [mem 0xa130000000-0xa1afffffff] (bus address [0x30000000-0xafffffff])


and here's what it looks like when it works:

[ 0.756793] xgene-pcie 1f500000.pcie: host bridge /soc/pcie@1f500000 ranges:
[ 0.756807] xgene-pcie 1f500000.pcie: No bus range found for /soc/pcie@1f500000, using [bus 00-ff]
[ 0.756822] xgene-pcie 1f500000.pcie: MEM 0xa130000000..0xa1afffffff -> 0x0030000000
[ 0.756838] xgene-pcie 1f500000.pcie: IB MEM 0x4000000000..0x7fffffffff -> 0x4000000000
[ 0.756892] xgene-pcie 1f500000.pcie: (rc) x8 gen-2 link up
[ 0.756962] xgene-pcie 1f500000.pcie: PCI host bridge to bus 0000:00
[ 0.756968] pci_bus 0000:00: root bus resource [bus 00-ff]
[ 0.756974] pci_bus 0000:00: root bus resource [mem 0xa130000000-0xa1afffffff] (bus address [0x30000000-0xafffffff])
[ 0.757006] pci 0000:00:00.0: [10e8:e004] type 01 class 0x060400
[ 0.757014] pci_bus 0000:00: 2-byte config write to 0000:00:00.0 offset 0x4 may corrupt adjacent RW1C bits
[ 0.757022] pci_bus 0000:00: 2-byte config write to 0000:00:00.0 offset 0x4 may corrupt adjacent RW1C bits
[ 0.757032] pci_bus 0000:00: 2-byte config write to 0000:00:00.0 offset 0x4 may corrupt adjacent RW1C bits
[ 0.757039] pci_bus 0000:00: 2-byte config write to 0000:00:00.0 offset 0x4 may corrupt adjacent RW1C bits
[ 0.757046] pci_bus 0000:00: 2-byte config write to 0000:00:00.0 offset 0x4 may corrupt adjacent RW1C bits
[ 0.757052] pci_bus 0000:00: 2-byte config write to 0000:00:00.0 offset 0x4 may corrupt adjacent RW1C bits
[ 0.757059] pci_bus 0000:00: 2-byte config write to 0000:00:00.0 offset 0x4 may corrupt adjacent RW1C bits
[ 0.757068] pci_bus 0000:00: 2-byte config write to 0000:00:00.0 offset 0x4 may corrupt adjacent RW1C bits
[ 0.757094] pci_bus 0000:00: 2-byte config write to 0000:00:00.0 offset 0x3e may corrupt adjacent RW1C bits
[ 0.757143] pci 0000:00:00.0: supports D1 D2
[ 0.757589] pci_bus 0000:00: 2-byte config write to 0000:00:00.0 offset 0x3e may corrupt adjacent RW1C bits
[ 0.757968] pci 0000:01:00.0: [15b3:1007] type 00 class 0x020000
[ 0.758381] pci 0000:01:00.0: reg 0x10: [mem 0x00100000-0x001fffff 64bit]
[ 0.758642] pci 0000:01:00.0: reg 0x18: [mem 0x00800000-0x00ffffff 64bit pref]
[ 0.761110] pci 0000:01:00.0: reg 0x134: [mem 0x00000000-0x007fffff 64bit pref]
[ 0.761115] pci 0000:01:00.0: VF(n) BAR2 space: [mem 0x00000000-0x03ffffff 64bit pref] (contains BAR2 for 8 VFs)
[ 0.762921] pci 0000:01:00.0: 32.000 Gb/s available PCIe bandwidth, limited by 5.0 GT/s PCIe x8 link at 0000:00:00.0 (capable of 63.008 Gb/s with 8.0 GT/s PCIe x8 link)
[ 0.773939] pci 0000:00:00.0: BAR 15: assigned [mem 0xa130000000-0xa1347fffff 64bit pref]
[ 0.773947] pci 0000:00:00.0: BAR 14: assigned [mem 0xa134800000-0xa1348fffff]
[ 0.773954] pci 0000:01:00.0: BAR 2: assigned [mem 0xa130000000-0xa1307fffff 64bit pref]
[ 0.774136] pci 0000:01:00.0: BAR 9: assigned [mem 0xa130800000-0xa1347fffff 64bit pref]
[ 0.774203] pci 0000:01:00.0: BAR 0: assigned [mem 0xa134800000-0xa1348fffff 64bit]
[ 0.774384] pci 0000:00:00.0: PCI bridge to [bus 01]
[ 0.774391] pci 0000:00:00.0: bridge window [mem 0xa134800000-0xa1348fffff]
[ 0.774397] pci 0000:00:00.0: bridge window [mem 0xa130000000-0xa1347fffff 64bit pref]
[ 0.774576] pcieport 0000:00:00.0: PME: Signaling with IRQ 89
[ 0.774734] pcieport 0000:00:00.0: AER: enabled with IRQ 89


-dann