Commit 5385edc5 authored by Ville Syrjala's avatar Ville Syrjala Committed by Pierre Ossman
Browse files

at91_mci: AT91SAM9260/9263 12 byte write erratum (v2) 



AT91SAM926[0/3] PDC must write at least 12 bytes. The code compiles and runs
but the actual condition for this erratum did not trigger in my tests so it's
unclear if it actually works as intended.

Signed-off-by: default avatarVille Syrjala <syrjala@sci.fi>
Signed-off-by: default avatarNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: default avatarPierre Ossman <drzeus@drzeus.cx>
parent fa1fe010

drivers/mmc/host/at91_mci.c

+17 −4
Original line number Diff line number Diff line
@@ -198,9 +198,14 @@ static inline void at91_mci_sg_to_dma(struct at91mci_host *host, struct mmc_data 
	unsigned int len, i, size;

	unsigned *dmabuf = host->buffer;



	size = host->total_length;

	size = data->blksz * data->blocks;

	len = data->sg_len;



	/* AT91SAM926[0/3] Data Write Operation and number of bytes erratum */

	if (cpu_is_at91sam9260() || cpu_is_at91sam9263())

		if (host->total_length == 12)

			memset(dmabuf, 0, 12);



	/*

	 * Just loop through all entries. Size might not

	 * be the entire list though so make sure that
@@ -222,9 +227,10 @@ static inline void at91_mci_sg_to_dma(struct at91mci_host *host, struct mmc_data 


			for (index = 0; index < (amount / 4); index++)

				*dmabuf++ = swab32(sgbuffer[index]);

		}

		else

		} else {

			memcpy(dmabuf, sgbuffer, amount);

			dmabuf += amount;

		}



		kunmap_atomic(sgbuffer, KM_BIO_SRC_IRQ);
@@ -417,7 +423,7 @@ static void at91_mci_update_bytes_xfered(struct at91mci_host *host) 
			/* card is in IDLE mode now */

			pr_debug("-> bytes_xfered %d, total_length = %d\n",

				data->bytes_xfered, host->total_length);

			data->bytes_xfered = host->total_length;

			data->bytes_xfered = data->blksz * data->blocks;

		}

	}

}
@@ -600,6 +606,13 @@ static void at91_mci_send_command(struct at91mci_host *host, struct mmc_command 
				 * Handle a write

				 */

				host->total_length = block_length * blocks;

				/*

				 * AT91SAM926[0/3] Data Write Operation and

				 * number of bytes erratum

				 */

				if (cpu_is_at91sam9260 () || cpu_is_at91sam9263())

					if (host->total_length < 12)

						host->total_length = 12;

				host->buffer = dma_alloc_coherent(NULL,

						host->total_length,

						&host->physical_address, GFP_KERNEL);

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