[PATCH 2/2] mci: atmel_mci: switch PBL implementation to common mci-pbl support

Ahmad Fatoum a.fatoum at pengutronix.de
Tue May 6 04:56:52 PDT 2025


We don't reinitialize the SD-Card when barebox is used as a first stage,
because it's already initialized by the BootROM and thus we don't use
the MMC stack. Recently, a very stripped down version was added that
doesn't initialize cards, but determines wheter a card is high or
standard capacity and then starts reading blocks directly.
Make use of it.

Signed-off-by: Ahmad Fatoum <a.fatoum at pengutronix.de>
---
 drivers/mci/atmel_mci_pbl.c | 99 +++++++------------------------------
 1 file changed, 18 insertions(+), 81 deletions(-)

diff --git a/drivers/mci/atmel_mci_pbl.c b/drivers/mci/atmel_mci_pbl.c
index d7343246abbb..27727b27343c 100644
--- a/drivers/mci/atmel_mci_pbl.c
+++ b/drivers/mci/atmel_mci_pbl.c
@@ -6,95 +6,32 @@
 
 #include "atmel-mci-regs.h"
 
-#define SECTOR_SIZE			512
 #define SUPPORT_MAX_BLOCKS		16U
 
-struct atmel_mci_priv {
-	struct atmel_mci host;
-	bool highcapacity_card;
-};
-
-static struct atmel_mci_priv atmci_sdcard;
-
-static int atmel_mci_pbl_stop_transmission(struct atmel_mci_priv *priv)
+static int pbl_atmci_common_request(struct pbl_mci *mci,
+				    struct mci_cmd *cmd,
+				    struct mci_data *data)
 {
-	struct mci_cmd cmd = {
-		.cmdidx = MMC_CMD_STOP_TRANSMISSION,
-		.resp_type = MMC_RSP_R1b,
-	};
-
-	return atmci_common_request(&priv->host, &cmd, NULL);
+	return atmci_common_request(mci->priv, cmd, data);
 }
 
-static int at91_mci_sd_cmd_read_multiple_block(struct atmel_mci_priv *priv,
-				      void *buf,
-				      unsigned int start,
-				      unsigned int block_count)
-{
-	u16 block_len = SECTOR_SIZE;
-	struct mci_data data;
-	struct mci_cmd cmd = {
-		.cmdidx = MMC_CMD_READ_MULTIPLE_BLOCK,
-		.resp_type = MMC_RSP_R1,
-		.cmdarg = start,
-	};
-
-	if (!priv->highcapacity_card)
-		cmd.cmdarg *= block_len;
-
-	data.dest = buf;
-	data.flags = MMC_DATA_READ;
-	data.blocksize = block_len;
-	data.blocks = block_count;
-
-	return atmci_common_request(&priv->host, &cmd, &data);
-}
-
-static int at91_mci_bio_read(struct pbl_bio *bio, off_t start,
-				void *buf, unsigned int nblocks)
-{
-	struct atmel_mci_priv *priv = bio->priv;
-	unsigned int blocks_done = 0;
-	unsigned int blocks;
-	unsigned int block_len = SECTOR_SIZE;
-	unsigned int blocks_read;
-	int ret;
-
-	while (blocks_done < nblocks) {
-		blocks = min(nblocks - blocks_done, SUPPORT_MAX_BLOCKS);
-
-		blocks_read = at91_mci_sd_cmd_read_multiple_block(priv, buf,
-							 start + blocks_done,
-							 blocks);
-
-		ret = atmel_mci_pbl_stop_transmission(priv);
-		if (ret)
-			return ret;
-
-		blocks_done += blocks_read;
-
-		if (blocks_read != blocks)
-			break;
-
-		buf += blocks * block_len;
-	}
-
-	return blocks_done;
-}
+static struct atmel_mci atmci_host;
+static struct pbl_mci mci;
 
 int at91_mci_bio_init(struct pbl_bio *bio, void __iomem *base,
 		      unsigned int clock, unsigned int slot,
 		      enum pbl_mci_capacity capacity)
 {
-	struct atmel_mci_priv *priv = &atmci_sdcard;
-	struct atmel_mci *host = &priv->host;
+	struct atmel_mci *host = &atmci_host;
 	struct mci_ios ios = { .bus_width = MMC_BUS_WIDTH_4, .clock = 25000000 };
 
-	/* PBL will get MCI controller in disabled state. We need to reconfigure
-	 * it. */
-	bio->priv = priv;
-	bio->read = at91_mci_bio_read;
+	mci.priv = host;
+	mci.send_cmd = pbl_atmci_common_request;
 
+	/*
+	 * PBL will get MCI controller in disabled state,
+	 * so we need to reconfigure it.
+	 */
 	host->regs = base;
 
 	atmci_get_cap(host);
@@ -112,10 +49,10 @@ int at91_mci_bio_init(struct pbl_bio *bio, void __iomem *base,
 
 	atmci_common_set_ios(host, &ios);
 
-	if (capacity == PBL_MCI_STANDARD_CAPACITY)
-		atmci_sdcard.highcapacity_card = false;
-	else
-		atmci_sdcard.highcapacity_card = true;
+	mci.priv = host;
+	mci.send_cmd = pbl_atmci_common_request;
+	mci.max_blocks_per_read = SUPPORT_MAX_BLOCKS;
+	mci.capacity = capacity;
 
-	return 0;
+	return pbl_mci_bio_init(&mci, bio);
 }
-- 
2.39.5




More information about the barebox mailing list