Re: [PATCH] PCI/ACPI: Add Ampere Altra SOC MCFG quirk

From: Bjorn Helgaas <helgaas@kernel.org>
To: Tuan Phan <tuanphan@os.amperecomputing.com>
Cc: patches@amperecomputing.com, Bjorn Helgaas <bhelgaas@google.com>,
	"Rafael J. Wysocki" <rjw@rjwysocki.net>,
	Len Brown <lenb@kernel.org>,
	linux-pci@vger.kernel.org, linux-acpi@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH] PCI/ACPI: Add Ampere Altra SOC MCFG quirk
Date: Thu, 17 Sep 2020 12:33:10 -0500	[thread overview]
Message-ID: <20200917173310.GA1714144@bjorn-Precision-5520> (raw)
In-Reply-To: <1596751055-12316-1-git-send-email-tuanphan@os.amperecomputing.com>

On Thu, Aug 06, 2020 at 02:57:34PM -0700, Tuan Phan wrote:
> Ampere Altra SOC supports only 32-bit ECAM reading. Therefore,
> add an MCFG quirk for the platform.
> 
> Signed-off-by: Tuan Phan <tuanphan@os.amperecomputing.com>

Applied to pci/enumeration for v5.10, thanks!

> ---
>  drivers/acpi/pci_mcfg.c  | 20 ++++++++++++++++++++
>  drivers/pci/ecam.c       | 10 ++++++++++
>  include/linux/pci-ecam.h |  1 +
>  3 files changed, 31 insertions(+)
> 
> diff --git a/drivers/acpi/pci_mcfg.c b/drivers/acpi/pci_mcfg.c
> index 54b36b7ad47d..e526571e0ebd 100644
> --- a/drivers/acpi/pci_mcfg.c
> +++ b/drivers/acpi/pci_mcfg.c
> @@ -142,6 +142,26 @@ static struct mcfg_fixup mcfg_quirks[] = {
>  	XGENE_V2_ECAM_MCFG(4, 0),
>  	XGENE_V2_ECAM_MCFG(4, 1),
>  	XGENE_V2_ECAM_MCFG(4, 2),
> +
> +#define ALTRA_ECAM_QUIRK(rev, seg) \
> +	{ "Ampere", "Altra   ", rev, seg, MCFG_BUS_ANY, &pci_32b_read_ops }
> +
> +	ALTRA_ECAM_QUIRK(1, 0),
> +	ALTRA_ECAM_QUIRK(1, 1),
> +	ALTRA_ECAM_QUIRK(1, 2),
> +	ALTRA_ECAM_QUIRK(1, 3),
> +	ALTRA_ECAM_QUIRK(1, 4),
> +	ALTRA_ECAM_QUIRK(1, 5),
> +	ALTRA_ECAM_QUIRK(1, 6),
> +	ALTRA_ECAM_QUIRK(1, 7),
> +	ALTRA_ECAM_QUIRK(1, 8),
> +	ALTRA_ECAM_QUIRK(1, 9),
> +	ALTRA_ECAM_QUIRK(1, 10),
> +	ALTRA_ECAM_QUIRK(1, 11),
> +	ALTRA_ECAM_QUIRK(1, 12),
> +	ALTRA_ECAM_QUIRK(1, 13),
> +	ALTRA_ECAM_QUIRK(1, 14),
> +	ALTRA_ECAM_QUIRK(1, 15),
>  };
>  
>  static char mcfg_oem_id[ACPI_OEM_ID_SIZE];
> diff --git a/drivers/pci/ecam.c b/drivers/pci/ecam.c
> index 8f065a42fc1a..b54d32a31669 100644
> --- a/drivers/pci/ecam.c
> +++ b/drivers/pci/ecam.c
> @@ -168,4 +168,14 @@ const struct pci_ecam_ops pci_32b_ops = {
>  		.write		= pci_generic_config_write32,
>  	}
>  };
> +
> +/* ECAM ops for 32-bit read only (non-compliant) */
> +const struct pci_ecam_ops pci_32b_read_ops = {
> +	.bus_shift	= 20,
> +	.pci_ops	= {
> +		.map_bus	= pci_ecam_map_bus,
> +		.read		= pci_generic_config_read32,
> +		.write		= pci_generic_config_write,
> +	}
> +};
>  #endif
> diff --git a/include/linux/pci-ecam.h b/include/linux/pci-ecam.h
> index 1af5cb02ef7f..033ce74f02e8 100644
> --- a/include/linux/pci-ecam.h
> +++ b/include/linux/pci-ecam.h
> @@ -51,6 +51,7 @@ extern const struct pci_ecam_ops pci_generic_ecam_ops;
>  
>  #if defined(CONFIG_ACPI) && defined(CONFIG_PCI_QUIRKS)
>  extern const struct pci_ecam_ops pci_32b_ops;	/* 32-bit accesses only */
> +extern const struct pci_ecam_ops pci_32b_read_ops; /* 32-bit read only */
>  extern const struct pci_ecam_ops hisi_pcie_ops;	/* HiSilicon */
>  extern const struct pci_ecam_ops thunder_pem_ecam_ops; /* Cavium ThunderX 1.x & 2.x */
>  extern const struct pci_ecam_ops pci_thunder_ecam_ops; /* Cavium ThunderX 1.x */
> -- 
> 2.18.4
> 