[PATCH v2 0/2] mmc: sdhci-pci: Use ACPI to set max frequency of sdio host controller

[PATCH v2 0/2] mmc: sdhci-pci: Use ACPI to set max frequency of sdio host controller

[Zach Brown]

On some boards, max SDIO frequency is limited by trace lengths and other layout
choices. We would like a way to specify this limitation so the driver can
behave accordingly.

This patch set assumes that the limitation has been reported in an ACPI table
which the driver can check to get the max frequency.

The first patch creates a PCI ID and support for the Intel byt sdio where NI is
the subvendor.

If CONFIG_ACPI is set, the second patch uses the ACPI table to set f_max during
the new ni_byt_sdio_probe_slot.

rv2:
   * Use acpi_evaluate_integer() instead of
     acpi_get_handle()/acpi_evaluate_object()
pv1:
   * Removed redundant comment
   * Print info message if MXFQ not found in acpi table
pv2:
   * Changed info message to error message if MXFQ not found
   * Replaced ni_byt_sdio_probe_slot with one of two versions depending on
     whether CONFIG_ACPI is set.

Zach Brown (2):
  mmc: sdhci-pci: Add PCI ID for Intel byt sdio host controller
    sub-vended by NI
  mmc: sdhci-pci: Use ACPI to get max frequency for Intel byt sdio
    controller sub-vended by NI

 drivers/mmc/host/sdhci-pci-core.c | 52 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 52 insertions(+)

--
2.7.4

[PATCH v2 1/2] mmc: sdhci-pci: Add PCI ID for Intel byt sdio host controller sub-vended by NI

[Zach Brown]

Add PCI ID for Intel byt sdio host controller sub-vended by NI.

The controller has different behavior because of the board layout NI
puts it on.

Signed-off-by: Zach Brown <zach.brown@ni.com>
---
 drivers/mmc/host/sdhci-pci-core.c | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/drivers/mmc/host/sdhci-pci-core.c b/drivers/mmc/host/sdhci-pci-core.c
index 1d9e00a..9741505 100644
--- a/drivers/mmc/host/sdhci-pci-core.c
+++ b/drivers/mmc/host/sdhci-pci-core.c
@@ -375,6 +375,13 @@ static int byt_emmc_probe_slot(struct sdhci_pci_slot *slot)
 	return 0;
 }
 
+static int ni_byt_sdio_probe_slot(struct sdhci_pci_slot *slot)
+{
+	slot->host->mmc->caps |= MMC_CAP_POWER_OFF_CARD | MMC_CAP_NONREMOVABLE |
+				 MMC_CAP_WAIT_WHILE_BUSY;
+	return 0;
+}
+
 static int byt_sdio_probe_slot(struct sdhci_pci_slot *slot)
 {
 	slot->host->mmc->caps |= MMC_CAP_POWER_OFF_CARD | MMC_CAP_NONREMOVABLE |
@@ -447,6 +454,15 @@ static const struct sdhci_pci_fixes sdhci_intel_byt_emmc = {
 	.ops		= &sdhci_intel_byt_ops,
 };
 
+static const struct sdhci_pci_fixes sdhci_ni_byt_sdio = {
+	.quirks		= SDHCI_QUIRK_NO_ENDATTR_IN_NOPDESC,
+	.quirks2	= SDHCI_QUIRK2_HOST_OFF_CARD_ON |
+			  SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
+	.allow_runtime_pm = true,
+	.probe_slot	= ni_byt_sdio_probe_slot,
+	.ops		= &sdhci_intel_byt_ops,
+};
+
 static const struct sdhci_pci_fixes sdhci_intel_byt_sdio = {
 	.quirks		= SDHCI_QUIRK_NO_ENDATTR_IN_NOPDESC,
 	.quirks2	= SDHCI_QUIRK2_HOST_OFF_CARD_ON |
@@ -1079,6 +1095,14 @@ static const struct pci_device_id pci_ids[] = {
 	{
 		.vendor		= PCI_VENDOR_ID_INTEL,
 		.device		= PCI_DEVICE_ID_INTEL_BYT_SDIO,
+		.subvendor	= PCI_VENDOR_ID_NI,
+		.subdevice	= 0x7884,
+		.driver_data	= (kernel_ulong_t)&sdhci_ni_byt_sdio,
+	},
+
+	{
+		.vendor		= PCI_VENDOR_ID_INTEL,
+		.device		= PCI_DEVICE_ID_INTEL_BYT_SDIO,
 		.subvendor	= PCI_ANY_ID,
 		.subdevice	= PCI_ANY_ID,
 		.driver_data	= (kernel_ulong_t)&sdhci_intel_byt_sdio,
-- 
2.7.4

[PATCH v2 2/2] mmc: sdhci-pci: Use ACPI to get max frequency for Intel byt sdio controller sub-vended by NI

[Zach Brown]

On NI 9037 boards the max SDIO frequency is limited by trace lengths
and other layout choices. The max SDIO frequency is stored in an ACPI
table.

The driver reads the ACPI entry MXFQ during sdio_probe_slot and sets the
f_max field of the host.

Signed-off-by: Nathan Sullivan <nathan.sullivan@ni.com>
Reviewed-by: Jaeden Amero <jaeden.amero@ni.com>
Reviewed-by: Josh Cartwright <joshc@ni.com>
Signed-off-by: Zach Brown <zach.brown@ni.com>
---
 drivers/mmc/host/sdhci-pci-core.c | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/drivers/mmc/host/sdhci-pci-core.c b/drivers/mmc/host/sdhci-pci-core.c
index 9741505..34284b8 100644
--- a/drivers/mmc/host/sdhci-pci-core.c
+++ b/drivers/mmc/host/sdhci-pci-core.c
@@ -27,6 +27,7 @@
 #include <linux/pm_runtime.h>
 #include <linux/mmc/slot-gpio.h>
 #include <linux/mmc/sdhci-pci-data.h>
+#include <linux/acpi.h>
 
 #include "sdhci.h"
 #include "sdhci-pci.h"
@@ -375,6 +376,30 @@ static int byt_emmc_probe_slot(struct sdhci_pci_slot *slot)
 	return 0;
 }
 
+#ifdef CONFIG_ACPI
+
+static int ni_byt_sdio_probe_slot(struct sdhci_pci_slot *slot)
+{
+	acpi_status status;
+	unsigned long long max_freq;
+
+	status = acpi_evaluate_integer(ACPI_HANDLE(&slot->chip->pdev->dev),
+				       "MXFQ", NULL, &max_freq);
+	if (ACPI_FAILURE(status)) {
+		dev_err(&slot->chip->pdev->dev,
+			"MXFQ not found in acpi table\n");
+		return -EINVAL;
+	}
+
+	slot->host->mmc->f_max = max_freq * 1000000;
+
+	slot->host->mmc->caps |= MMC_CAP_POWER_OFF_CARD | MMC_CAP_NONREMOVABLE |
+				 MMC_CAP_WAIT_WHILE_BUSY;
+	return 0;
+}
+
+#else
+
 static int ni_byt_sdio_probe_slot(struct sdhci_pci_slot *slot)
 {
 	slot->host->mmc->caps |= MMC_CAP_POWER_OFF_CARD | MMC_CAP_NONREMOVABLE |
@@ -382,6 +407,9 @@ static int ni_byt_sdio_probe_slot(struct sdhci_pci_slot *slot)
 	return 0;
 }
 
+#endif
+
+
 static int byt_sdio_probe_slot(struct sdhci_pci_slot *slot)
 {
 	slot->host->mmc->caps |= MMC_CAP_POWER_OFF_CARD | MMC_CAP_NONREMOVABLE |
-- 
2.7.4

Re: [PATCH v2 2/2] mmc: sdhci-pci: Use ACPI to get max frequency for Intel byt sdio controller sub-vended by NI

[Adrian Hunter]

On 22/11/16 23:53, Zach Brown wrote:
> On NI 9037 boards the max SDIO frequency is limited by trace lengths
> and other layout choices. The max SDIO frequency is stored in an ACPI
> table.
> 
> The driver reads the ACPI entry MXFQ during sdio_probe_slot and sets the
> f_max field of the host.
> 
> Signed-off-by: Nathan Sullivan <nathan.sullivan@ni.com>
> Reviewed-by: Jaeden Amero <jaeden.amero@ni.com>
> Reviewed-by: Josh Cartwright <joshc@ni.com>
> Signed-off-by: Zach Brown <zach.brown@ni.com>
> ---
>  drivers/mmc/host/sdhci-pci-core.c | 28 ++++++++++++++++++++++++++++
>  1 file changed, 28 insertions(+)
> 
> diff --git a/drivers/mmc/host/sdhci-pci-core.c b/drivers/mmc/host/sdhci-pci-core.c
> index 9741505..34284b8 100644
> --- a/drivers/mmc/host/sdhci-pci-core.c
> +++ b/drivers/mmc/host/sdhci-pci-core.c
> @@ -27,6 +27,7 @@
>  #include <linux/pm_runtime.h>
>  #include <linux/mmc/slot-gpio.h>
>  #include <linux/mmc/sdhci-pci-data.h>
> +#include <linux/acpi.h>
>  
>  #include "sdhci.h"
>  #include "sdhci-pci.h"
> @@ -375,6 +376,30 @@ static int byt_emmc_probe_slot(struct sdhci_pci_slot *slot)
>  	return 0;
>  }
>  
> +#ifdef CONFIG_ACPI
> +
> +static int ni_byt_sdio_probe_slot(struct sdhci_pci_slot *slot)
> +{
> +	acpi_status status;
> +	unsigned long long max_freq;
> +
> +	status = acpi_evaluate_integer(ACPI_HANDLE(&slot->chip->pdev->dev),
> +				       "MXFQ", NULL, &max_freq);
> +	if (ACPI_FAILURE(status)) {
> +		dev_err(&slot->chip->pdev->dev,
> +			"MXFQ not found in acpi table\n");
> +		return -EINVAL;
> +	}
> +
> +	slot->host->mmc->f_max = max_freq * 1000000;
> +
> +	slot->host->mmc->caps |= MMC_CAP_POWER_OFF_CARD | MMC_CAP_NONREMOVABLE |
> +				 MMC_CAP_WAIT_WHILE_BUSY;
> +	return 0;
> +}
> +
> +#else

No, it is the ACPI access that needs to be a separate function.  We don't
want 2 ni_byt_sdio_probe_slot(). Perhaps, something like:

#ifdef CONFIG_ACPI
static int ni_set_max_freq(struct sdhci_pci_slot *slot)
{
	acpi_status status;
	unsigned long long max_freq;

	status = acpi_evaluate_integer(ACPI_HANDLE(&slot->chip->pdev->dev),
				       "MXFQ", NULL, &max_freq);
	if (ACPI_FAILURE(status))
		dev_err(&slot->chip->pdev->dev,
			"MXFQ not found in acpi table\n");
		return -EINVAL;
	}

	slot->host->mmc->f_max = max_freq * 1000000;

	return 0;
}
#else
static inline int ni_set_max_freq(struct sdhci_pci_slot *slot)
{
	return 0;
}
#endif