[PATCH 1/1] mci: bcm2835: support 8bit bus width

[PATCH 1/1] mci: bcm2835: support 8bit bus width

[Pierre-Olivier Huard]

Using Raspberry Pi CM4s target generate a warning:

WARNING: bcm2835_mci fe340000.mmc@7e340000.of: Unsupported width received: 3
mmc0: mci_send_ext_csd failed with -5

Adding the support of 8 bits bus width resolve the issue.

Signed-off-by: Pierre-Olivier Huard <pierre-olivier.huard@rtone.fr>
---
 drivers/mci/mci-bcm2835.c | 7 +++++++
 drivers/mci/mci-bcm2835.h | 1 +
 2 files changed, 8 insertions(+)

diff --git a/drivers/mci/mci-bcm2835.c b/drivers/mci/mci-bcm2835.c
index 2b541e4c05..35cf0c4241 100644
--- a/drivers/mci/mci-bcm2835.c
+++ b/drivers/mci/mci-bcm2835.c
@@ -225,6 +225,13 @@ static void bcm2835_mci_set_ios(struct mci_host *mci, struct mci_ios *ios)
 			SDHCI_HOST_CONTROL__POWER_CONTROL__BLOCK_GAP_CONTROL);
 
 	switch (ios->bus_width) {
+	case MMC_BUS_WIDTH_8:
+		sdhci_write32(&host->sdhci,
+				SDHCI_HOST_CONTROL__POWER_CONTROL__BLOCK_GAP_CONTROL,
+				(current_val & ~CONTROL0_4DATA) | CONTROL0_8DATA);
+		host->bus_width = 2;
+		dev_dbg(host->hw_dev, "Changing bus width to 8\n");
+		break;
 	case MMC_BUS_WIDTH_4:
 		sdhci_write32(&host->sdhci,
 				SDHCI_HOST_CONTROL__POWER_CONTROL__BLOCK_GAP_CONTROL,
diff --git a/drivers/mci/mci-bcm2835.h b/drivers/mci/mci-bcm2835.h
index 608764c23d..71448642ad 100644
--- a/drivers/mci/mci-bcm2835.h
+++ b/drivers/mci/mci-bcm2835.h
@@ -10,6 +10,7 @@
 
 #define CONTROL0_HISPEED	(1 << 2)
 #define CONTROL0_4DATA		(1 << 1)
+#define CONTROL0_8DATA		(1 << 5)
 
 #define CONTROL1_DATARST	(1 << 26)
 #define CONTROL1_CMDRST		(1 << 25)
-- 
2.43.0

Re: [PATCH 1/1] mci: bcm2835: support 8bit bus width

[Sascha Hauer]

On Thu, 15 Feb 2024 13:01:39 +0100, Pierre-Olivier Huard wrote:
> Using Raspberry Pi CM4s target generate a warning:
> 
> WARNING: bcm2835_mci fe340000.mmc@7e340000.of: Unsupported width received: 3
> mmc0: mci_send_ext_csd failed with -5
> 
> Adding the support of 8 bits bus width resolve the issue.
> 
> [...]

Applied, thanks!

[1/1] mci: bcm2835: support 8bit bus width
      https://git.pengutronix.de/cgit/barebox/commit/?id=21cdaeab3cf3 (link may not be stable)

Best regards,
-- 
Sascha Hauer <s.hauer@pengutronix.de>