Re: [PATCH] mmc: sdhci-iproc: Add ACPI bindings for the rpi4

From: Stefan Wahren <stefan.wahren@i2se.com>
To: Jeremy Linton <jeremy.linton@arm.com>,
	linux-mmc@vger.kernel.org,
	Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Cc: ulf.hansson@linaro.org, f.fainelli@gmail.com,
	sbranden@broadcom.com, rjui@broadcom.com,
	adrian.hunter@intel.com, linux-kernel@vger.kernel.org,
	bcm-kernel-feedback-list@broadcom.com,
	linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH] mmc: sdhci-iproc: Add ACPI bindings for the rpi4
Date: Sat, 9 Jan 2021 12:07:40 +0100	[thread overview]
Message-ID: <ab3b5788-1148-636a-751f-0a31c87dda33@i2se.com> (raw)
In-Reply-To: <20210108211339.1724769-1-jeremy.linton@arm.com>

Hi Jeremy,

+add Nicolas

Am 08.01.21 um 22:13 schrieb Jeremy Linton:
> The rpi4 has a Arasan controller it carries over
> from the rpi3, and a newer eMMC2 controller.
> Because of a couple "quirks" it seems wiser to bind
> these controllers to the same driver that DT is using
> on this platform rather than the generic sdhci_acpi
> driver with PNP0D40.
>
> So, we use BCM2847 for the older Arasan and BRCME88C
> for the newer eMMC2.
>
> With this change linux is capable of utilizing the
> SD card slot, and the wifi on this platform
> with linux.
>
> Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
> ---
>  drivers/mmc/host/sdhci-iproc.c | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
>
> diff --git a/drivers/mmc/host/sdhci-iproc.c b/drivers/mmc/host/sdhci-iproc.c
> index c9434b461aab..f79d97b41805 100644
> --- a/drivers/mmc/host/sdhci-iproc.c
> +++ b/drivers/mmc/host/sdhci-iproc.c
> @@ -250,6 +250,14 @@ static const struct sdhci_pltfm_data sdhci_bcm2835_pltfm_data = {
>  	.ops = &sdhci_iproc_32only_ops,
>  };
>  
> +static const struct sdhci_pltfm_data sdhci_bcm_arasan_data = {
> +	.quirks = SDHCI_QUIRK_BROKEN_CARD_DETECTION |
> +		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
> +		  SDHCI_QUIRK_NO_HISPD_BIT,
> +	.quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
> +	.ops = &sdhci_iproc_32only_ops,
> +};
Why do we need an almost exact copy of bcm2835_data which works fine for
all Raspberry Pi boards?
> +
>  static const struct sdhci_iproc_data bcm2835_data = {
>  	.pdata = &sdhci_bcm2835_pltfm_data,
>  	.caps = ((0x1 << SDHCI_MAX_BLOCK_SHIFT)
> @@ -261,6 +269,10 @@ static const struct sdhci_iproc_data bcm2835_data = {
>  	.mmc_caps = 0x00000000,
>  };
>  
> +static const struct sdhci_iproc_data bcm_arasan_data = {
> +	.pdata = &sdhci_bcm_arasan_data,
> +};
> +
>  static const struct sdhci_ops sdhci_iproc_bcm2711_ops = {
>  	.read_l = sdhci_iproc_readl,
>  	.read_w = sdhci_iproc_readw,
> @@ -299,6 +311,8 @@ MODULE_DEVICE_TABLE(of, sdhci_iproc_of_match);
>  static const struct acpi_device_id sdhci_iproc_acpi_ids[] = {
>  	{ .id = "BRCM5871", .driver_data = (kernel_ulong_t)&iproc_cygnus_data },
>  	{ .id = "BRCM5872", .driver_data = (kernel_ulong_t)&iproc_data },
> +	{ .id = "BCM2847",  .driver_data = (kernel_ulong_t)&bcm_arasan_data },

Sorry, i don't have deeper knowledge about ACPI, but BCM2837 is the
official naming of the SoC on the RPi 3.

Is this a typo in the id?

> +	{ .id = "BRCME88C", .driver_data = (kernel_ulong_t)&bcm2711_data },
>  	{ /* sentinel */ }
>  };
>  MODULE_DEVICE_TABLE(acpi, sdhci_iproc_acpi_ids);