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[PATCH] USB: pci-quirks: Fix HCCPARAMS register error for LS7A EHCI

Huacai Chen posted 1 patch 1 year ago
There is a newer version of this series
drivers/usb/host/pci-quirks.c | 4 ++++
include/linux/pci_ids.h       | 1 +
2 files changed, 5 insertions(+)
[PATCH] USB: pci-quirks: Fix HCCPARAMS register error for LS7A EHCI
Posted by Huacai Chen 1 year ago 
LS7A EHCI controller doesn't have extended capabilities, so the EECP
(EHCI Extended Capabilities Pointer) field of HCCPARAMS register should
be 0x0, but it reads as 0xa0 now. This is a hardware flaw and will be
fixed in future, now just clear the EECP field to avoid error messages
on boot:

......
[    0.581675] pci 0000:00:04.1: EHCI: unrecognized capability ff
[    0.581699] pci 0000:00:04.1: EHCI: unrecognized capability ff
[    0.581716] pci 0000:00:04.1: EHCI: unrecognized capability ff
[    0.581851] pci 0000:00:04.1: EHCI: unrecognized capability ff
......
[    0.581916] pci 0000:00:05.1: EHCI: unrecognized capability ff
[    0.581951] pci 0000:00:05.1: EHCI: unrecognized capability ff
[    0.582704] pci 0000:00:05.1: EHCI: unrecognized capability ff
[    0.582799] pci 0000:00:05.1: EHCI: unrecognized capability ff
......

Cc: stable@vger.kernel.org
Signed-off-by: Baoqi Zhang <zhangbaoqi@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
---
 drivers/usb/host/pci-quirks.c | 4 ++++
 include/linux/pci_ids.h       | 1 +
 2 files changed, 5 insertions(+)

diff --git a/drivers/usb/host/pci-quirks.c b/drivers/usb/host/pci-quirks.c
index 1f9c1b1435d8..7e3151400a5e 100644
--- a/drivers/usb/host/pci-quirks.c
+++ b/drivers/usb/host/pci-quirks.c
@@ -958,6 +958,10 @@ static void quirk_usb_disable_ehci(struct pci_dev *pdev)
 	 * booting from USB disk or using a usb keyboard
 	 */
 	hcc_params = readl(base + EHCI_HCC_PARAMS);
+	if (pdev->vendor == PCI_VENDOR_ID_LOONGSON &&
+	    pdev->device == PCI_DEVICE_ID_LOONGSON_EHCI)
+		hcc_params &= ~(0xffL << 8);
+
 	offset = (hcc_params >> 8) & 0xff;
 	while (offset && --count) {
 		pci_read_config_dword(pdev, offset, &cap);
diff --git a/include/linux/pci_ids.h b/include/linux/pci_ids.h
index de5deb1a0118..74a84834d9eb 100644
--- a/include/linux/pci_ids.h
+++ b/include/linux/pci_ids.h
@@ -162,6 +162,7 @@
 
 #define PCI_VENDOR_ID_LOONGSON		0x0014
 
+#define PCI_DEVICE_ID_LOONGSON_EHCI     0x7a14
 #define PCI_DEVICE_ID_LOONGSON_HDA      0x7a07
 #define PCI_DEVICE_ID_LOONGSON_HDMI     0x7a37
 
-- 
2.47.1
Re: [PATCH] USB: pci-quirks: Fix HCCPARAMS register error for LS7A EHCI
Posted by Alan Stern 1 year ago 
On Fri, Jan 31, 2025 at 06:06:51PM +0800, Huacai Chen wrote:
> LS7A EHCI controller doesn't have extended capabilities, so the EECP
> (EHCI Extended Capabilities Pointer) field of HCCPARAMS register should
> be 0x0, but it reads as 0xa0 now. This is a hardware flaw and will be
> fixed in future, now just clear the EECP field to avoid error messages
> on boot:
> 
> ......
> [    0.581675] pci 0000:00:04.1: EHCI: unrecognized capability ff
> [    0.581699] pci 0000:00:04.1: EHCI: unrecognized capability ff
> [    0.581716] pci 0000:00:04.1: EHCI: unrecognized capability ff
> [    0.581851] pci 0000:00:04.1: EHCI: unrecognized capability ff
> ......
> [    0.581916] pci 0000:00:05.1: EHCI: unrecognized capability ff
> [    0.581951] pci 0000:00:05.1: EHCI: unrecognized capability ff
> [    0.582704] pci 0000:00:05.1: EHCI: unrecognized capability ff
> [    0.582799] pci 0000:00:05.1: EHCI: unrecognized capability ff
> ......
> 
> Cc: stable@vger.kernel.org
> Signed-off-by: Baoqi Zhang <zhangbaoqi@loongson.cn>
> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
> ---
>  drivers/usb/host/pci-quirks.c | 4 ++++
>  include/linux/pci_ids.h       | 1 +
>  2 files changed, 5 insertions(+)
> 
> diff --git a/drivers/usb/host/pci-quirks.c b/drivers/usb/host/pci-quirks.c
> index 1f9c1b1435d8..7e3151400a5e 100644
> --- a/drivers/usb/host/pci-quirks.c
> +++ b/drivers/usb/host/pci-quirks.c
> @@ -958,6 +958,10 @@ static void quirk_usb_disable_ehci(struct pci_dev *pdev)
>  	 * booting from USB disk or using a usb keyboard
>  	 */
>  	hcc_params = readl(base + EHCI_HCC_PARAMS);
> +	if (pdev->vendor == PCI_VENDOR_ID_LOONGSON &&
> +	    pdev->device == PCI_DEVICE_ID_LOONGSON_EHCI)
> +		hcc_params &= ~(0xffL << 8);

Can you please add a comment before this "if" statement explaining why 
it is necessary?

Alan Stern

> +
>  	offset = (hcc_params >> 8) & 0xff;
>  	while (offset && --count) {
>  		pci_read_config_dword(pdev, offset, &cap);
> diff --git a/include/linux/pci_ids.h b/include/linux/pci_ids.h
> index de5deb1a0118..74a84834d9eb 100644
> --- a/include/linux/pci_ids.h
> +++ b/include/linux/pci_ids.h
> @@ -162,6 +162,7 @@
>  
>  #define PCI_VENDOR_ID_LOONGSON		0x0014
>  
> +#define PCI_DEVICE_ID_LOONGSON_EHCI     0x7a14
>  #define PCI_DEVICE_ID_LOONGSON_HDA      0x7a07
>  #define PCI_DEVICE_ID_LOONGSON_HDMI     0x7a37
>  
> -- 
> 2.47.1
>
Re: [PATCH] USB: pci-quirks: Fix HCCPARAMS register error for LS7A EHCI
Posted by Huacai Chen 1 year ago 
Hi, Alan,

On Fri, Jan 31, 2025 at 11:18 PM Alan Stern <stern@rowland.harvard.edu> wrote:
>
> On Fri, Jan 31, 2025 at 06:06:51PM +0800, Huacai Chen wrote:
> > LS7A EHCI controller doesn't have extended capabilities, so the EECP
> > (EHCI Extended Capabilities Pointer) field of HCCPARAMS register should
> > be 0x0, but it reads as 0xa0 now. This is a hardware flaw and will be
> > fixed in future, now just clear the EECP field to avoid error messages
> > on boot:
> >
> > ......
> > [    0.581675] pci 0000:00:04.1: EHCI: unrecognized capability ff
> > [    0.581699] pci 0000:00:04.1: EHCI: unrecognized capability ff
> > [    0.581716] pci 0000:00:04.1: EHCI: unrecognized capability ff
> > [    0.581851] pci 0000:00:04.1: EHCI: unrecognized capability ff
> > ......
> > [    0.581916] pci 0000:00:05.1: EHCI: unrecognized capability ff
> > [    0.581951] pci 0000:00:05.1: EHCI: unrecognized capability ff
> > [    0.582704] pci 0000:00:05.1: EHCI: unrecognized capability ff
> > [    0.582799] pci 0000:00:05.1: EHCI: unrecognized capability ff
> > ......
> >
> > Cc: stable@vger.kernel.org
> > Signed-off-by: Baoqi Zhang <zhangbaoqi@loongson.cn>
> > Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
> > ---
> >  drivers/usb/host/pci-quirks.c | 4 ++++
> >  include/linux/pci_ids.h       | 1 +
> >  2 files changed, 5 insertions(+)
> >
> > diff --git a/drivers/usb/host/pci-quirks.c b/drivers/usb/host/pci-quirks.c
> > index 1f9c1b1435d8..7e3151400a5e 100644
> > --- a/drivers/usb/host/pci-quirks.c
> > +++ b/drivers/usb/host/pci-quirks.c
> > @@ -958,6 +958,10 @@ static void quirk_usb_disable_ehci(struct pci_dev *pdev)
> >        * booting from USB disk or using a usb keyboard
> >        */
> >       hcc_params = readl(base + EHCI_HCC_PARAMS);
> > +     if (pdev->vendor == PCI_VENDOR_ID_LOONGSON &&
> > +         pdev->device == PCI_DEVICE_ID_LOONGSON_EHCI)
> > +             hcc_params &= ~(0xffL << 8);
>
> Can you please add a comment before this "if" statement explaining why
> it is necessary?
OK, will do in next version.

Huacai
>
> Alan Stern
>
> > +
> >       offset = (hcc_params >> 8) & 0xff;
> >       while (offset && --count) {
> >               pci_read_config_dword(pdev, offset, &cap);
> > diff --git a/include/linux/pci_ids.h b/include/linux/pci_ids.h
> > index de5deb1a0118..74a84834d9eb 100644
> > --- a/include/linux/pci_ids.h
> > +++ b/include/linux/pci_ids.h
> > @@ -162,6 +162,7 @@
> >
> >  #define PCI_VENDOR_ID_LOONGSON               0x0014
> >
> > +#define PCI_DEVICE_ID_LOONGSON_EHCI     0x7a14
> >  #define PCI_DEVICE_ID_LOONGSON_HDA      0x7a07
> >  #define PCI_DEVICE_ID_LOONGSON_HDMI     0x7a37
> >
> > --
> > 2.47.1
> >
Re: [PATCH] USB: pci-quirks: Fix HCCPARAMS register error for LS7A EHCI
Posted by Greg Kroah-Hartman 1 year ago 
On Fri, Jan 31, 2025 at 06:06:51PM +0800, Huacai Chen wrote:
> LS7A EHCI controller doesn't have extended capabilities, so the EECP
> (EHCI Extended Capabilities Pointer) field of HCCPARAMS register should
> be 0x0, but it reads as 0xa0 now. This is a hardware flaw and will be
> fixed in future, now just clear the EECP field to avoid error messages
> on boot:
> 
> ......
> [    0.581675] pci 0000:00:04.1: EHCI: unrecognized capability ff
> [    0.581699] pci 0000:00:04.1: EHCI: unrecognized capability ff
> [    0.581716] pci 0000:00:04.1: EHCI: unrecognized capability ff
> [    0.581851] pci 0000:00:04.1: EHCI: unrecognized capability ff
> ......
> [    0.581916] pci 0000:00:05.1: EHCI: unrecognized capability ff
> [    0.581951] pci 0000:00:05.1: EHCI: unrecognized capability ff
> [    0.582704] pci 0000:00:05.1: EHCI: unrecognized capability ff
> [    0.582799] pci 0000:00:05.1: EHCI: unrecognized capability ff
> ......
> 
> Cc: stable@vger.kernel.org
> Signed-off-by: Baoqi Zhang <zhangbaoqi@loongson.cn>
> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
> ---
>  drivers/usb/host/pci-quirks.c | 4 ++++
>  include/linux/pci_ids.h       | 1 +
>  2 files changed, 5 insertions(+)
> 
> diff --git a/drivers/usb/host/pci-quirks.c b/drivers/usb/host/pci-quirks.c
> index 1f9c1b1435d8..7e3151400a5e 100644
> --- a/drivers/usb/host/pci-quirks.c
> +++ b/drivers/usb/host/pci-quirks.c
> @@ -958,6 +958,10 @@ static void quirk_usb_disable_ehci(struct pci_dev *pdev)
>  	 * booting from USB disk or using a usb keyboard
>  	 */
>  	hcc_params = readl(base + EHCI_HCC_PARAMS);
> +	if (pdev->vendor == PCI_VENDOR_ID_LOONGSON &&
> +	    pdev->device == PCI_DEVICE_ID_LOONGSON_EHCI)
> +		hcc_params &= ~(0xffL << 8);
> +
>  	offset = (hcc_params >> 8) & 0xff;
>  	while (offset && --count) {
>  		pci_read_config_dword(pdev, offset, &cap);
> diff --git a/include/linux/pci_ids.h b/include/linux/pci_ids.h
> index de5deb1a0118..74a84834d9eb 100644
> --- a/include/linux/pci_ids.h
> +++ b/include/linux/pci_ids.h
> @@ -162,6 +162,7 @@
>  
>  #define PCI_VENDOR_ID_LOONGSON		0x0014
>  
> +#define PCI_DEVICE_ID_LOONGSON_EHCI     0x7a14

If you read the top of this file, does this patch meet the requirement
to add this entry here to this file?

thanks,

greg k-h
Re: [PATCH] USB: pci-quirks: Fix HCCPARAMS register error for LS7A EHCI
Posted by Huacai Chen 1 year ago 
Hi, Greg,

On Fri, Jan 31, 2025 at 6:48 PM Greg Kroah-Hartman
<gregkh@linuxfoundation.org> wrote:
>
> On Fri, Jan 31, 2025 at 06:06:51PM +0800, Huacai Chen wrote:
> > LS7A EHCI controller doesn't have extended capabilities, so the EECP
> > (EHCI Extended Capabilities Pointer) field of HCCPARAMS register should
> > be 0x0, but it reads as 0xa0 now. This is a hardware flaw and will be
> > fixed in future, now just clear the EECP field to avoid error messages
> > on boot:
> >
> > ......
> > [    0.581675] pci 0000:00:04.1: EHCI: unrecognized capability ff
> > [    0.581699] pci 0000:00:04.1: EHCI: unrecognized capability ff
> > [    0.581716] pci 0000:00:04.1: EHCI: unrecognized capability ff
> > [    0.581851] pci 0000:00:04.1: EHCI: unrecognized capability ff
> > ......
> > [    0.581916] pci 0000:00:05.1: EHCI: unrecognized capability ff
> > [    0.581951] pci 0000:00:05.1: EHCI: unrecognized capability ff
> > [    0.582704] pci 0000:00:05.1: EHCI: unrecognized capability ff
> > [    0.582799] pci 0000:00:05.1: EHCI: unrecognized capability ff
> > ......
> >
> > Cc: stable@vger.kernel.org
> > Signed-off-by: Baoqi Zhang <zhangbaoqi@loongson.cn>
> > Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
> > ---
> >  drivers/usb/host/pci-quirks.c | 4 ++++
> >  include/linux/pci_ids.h       | 1 +
> >  2 files changed, 5 insertions(+)
> >
> > diff --git a/drivers/usb/host/pci-quirks.c b/drivers/usb/host/pci-quirks.c
> > index 1f9c1b1435d8..7e3151400a5e 100644
> > --- a/drivers/usb/host/pci-quirks.c
> > +++ b/drivers/usb/host/pci-quirks.c
> > @@ -958,6 +958,10 @@ static void quirk_usb_disable_ehci(struct pci_dev *pdev)
> >        * booting from USB disk or using a usb keyboard
> >        */
> >       hcc_params = readl(base + EHCI_HCC_PARAMS);
> > +     if (pdev->vendor == PCI_VENDOR_ID_LOONGSON &&
> > +         pdev->device == PCI_DEVICE_ID_LOONGSON_EHCI)
> > +             hcc_params &= ~(0xffL << 8);
> > +
> >       offset = (hcc_params >> 8) & 0xff;
> >       while (offset && --count) {
> >               pci_read_config_dword(pdev, offset, &cap);
> > diff --git a/include/linux/pci_ids.h b/include/linux/pci_ids.h
> > index de5deb1a0118..74a84834d9eb 100644
> > --- a/include/linux/pci_ids.h
> > +++ b/include/linux/pci_ids.h
> > @@ -162,6 +162,7 @@
> >
> >  #define PCI_VENDOR_ID_LOONGSON               0x0014
> >
> > +#define PCI_DEVICE_ID_LOONGSON_EHCI     0x7a14
>
> If you read the top of this file, does this patch meet the requirement
> to add this entry here to this file?
Emmm, the device id is also used in
drivers/pci/controller/pci-loongson.c, but uses another code style so
it is not suitable to share the definition. Maybe the best solution is
use 0x7a14 directly.

Huacai
>
> thanks,
>
> greg k-h

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