diff mbox series

[v8,2/9] PCI: mediatek: Fix class type for MT7622 as PCI_CLASS_BRIDGE_PCI

Message ID 1539590940-13355-3-git-send-email-honghui.zhang@mediatek.com (mailing list archive)
State New, archived
Delegated to: Bjorn Helgaas
Headers show
Series PCI: mediatek: fixup find_port, enable_msi and add PM, module support | expand

Commit Message

Honghui Zhang Oct. 15, 2018, 8:08 a.m. UTC 
From: Honghui Zhang <honghui.zhang@mediatek.com>

The commit 101c92dc80c8 ("PCI: mediatek: Set up vendor ID and class
type for MT7622") have set the class type for MT7622 as un-properly
value of PCI_CLASS_BRIDGE_HOST.

The PCIe controller of MT7622 is complexed with Root Port and PCI-to-PCI
bridge, the bridge has type 1 configuration space header and related bridge
windows. The HW default value of this bridge's class type is invalid. Fix
its class type as PCI_CLASS_BRIDGE_PCI since it is HW defines.

Making the bridge visiable to PCI framework by setting its class type
properly will get its bridge windows configurated during PCI device
enumerate.

Fixes: 101c92dc80c8 ("PCI: mediatek: Set up vendor ID and class type for MT7622")
Signed-off-by: Honghui Zhang <honghui.zhang@mediatek.com>
Acked-by: Ryder Lee <ryder.lee@mediatek.com>
---
 drivers/pci/controller/pcie-mediatek.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Bjorn Helgaas Oct. 15, 2018, 6:37 p.m. UTC | #1 
On Mon, Oct 15, 2018 at 04:08:53PM +0800, honghui.zhang@mediatek.com wrote:
> From: Honghui Zhang <honghui.zhang@mediatek.com>
> 
> The commit 101c92dc80c8 ("PCI: mediatek: Set up vendor ID and class
> type for MT7622") have set the class type for MT7622 as un-properly
> value of PCI_CLASS_BRIDGE_HOST.
> 
> The PCIe controller of MT7622 is complexed with Root Port and PCI-to-PCI
> bridge, the bridge has type 1 configuration space header and related bridge
> windows. The HW default value of this bridge's class type is invalid. Fix
> its class type as PCI_CLASS_BRIDGE_PCI since it is HW defines.
> 
> Making the bridge visiable to PCI framework by setting its class type
> properly will get its bridge windows configurated during PCI device
> enumerate.
> 
> Fixes: 101c92dc80c8 ("PCI: mediatek: Set up vendor ID and class type for MT7622")
> Signed-off-by: Honghui Zhang <honghui.zhang@mediatek.com>
> Acked-by: Ryder Lee <ryder.lee@mediatek.com>

Nak until this patch is preceded by one that fixes the PCI core defect
I pointed out earlier [1].  It's OK to change the class code, but
not as a way of working around that PCI core defect.

[1] https://lore.kernel.org/linux-pci/20181012141202.GV5906@bhelgaas-glaptop.roam.corp.google.com

> ---
>  drivers/pci/controller/pcie-mediatek.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/pci/controller/pcie-mediatek.c b/drivers/pci/controller/pcie-mediatek.c
> index 288b8e2..bcdac9b 100644
> --- a/drivers/pci/controller/pcie-mediatek.c
> +++ b/drivers/pci/controller/pcie-mediatek.c
> @@ -432,7 +432,7 @@ static int mtk_pcie_startup_port_v2(struct mtk_pcie_port *port)
>  		val = PCI_VENDOR_ID_MEDIATEK;
>  		writew(val, port->base + PCIE_CONF_VEND_ID);
>  
> -		val = PCI_CLASS_BRIDGE_HOST;
> +		val = PCI_CLASS_BRIDGE_PCI;
>  		writew(val, port->base + PCIE_CONF_CLASS_ID);
>  	}
>  
> -- 
> 2.6.4
> 
> 
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
diff mbox series

Patch

diff --git a/drivers/pci/controller/pcie-mediatek.c b/drivers/pci/controller/pcie-mediatek.c
index 288b8e2..bcdac9b 100644
--- a/drivers/pci/controller/pcie-mediatek.c
+++ b/drivers/pci/controller/pcie-mediatek.c
@@ -432,7 +432,7 @@  static int mtk_pcie_startup_port_v2(struct mtk_pcie_port *port)
 		val = PCI_VENDOR_ID_MEDIATEK;
 		writew(val, port->base + PCIE_CONF_VEND_ID);
 
-		val = PCI_CLASS_BRIDGE_HOST;
+		val = PCI_CLASS_BRIDGE_PCI;
 		writew(val, port->base + PCIE_CONF_CLASS_ID);
 	}