Commit daf5822f authored by Sonic Zhang's avatar Sonic Zhang Committed by Greg Kroah-Hartman

USB: musb: add notes for Blackfin anomalies

Add some helpful notes about how the driver works around different
anomalies that exist in the on-chip host controller.
Signed-off-by: default avatarSonic Zhang <sonic.zhang@analog.com>
Signed-off-by: default avatarCliff Cai <cliff.cai@analog.com>
Signed-off-by: default avatarMike Frysinger <vapier@gentoo.org>
Signed-off-by: default avatarAnand Gadiyar <gadiyar@ti.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 1c47cb01
......@@ -14,6 +14,33 @@
* Blackfin specific definitions
*/
/* Anomalies notes:
*
* 05000450 - USB DMA Mode 1 Short Packet Data Corruption:
* MUSB driver is designed to transfer buffer of N * maxpacket size
* in DMA mode 1 and leave the rest of the data to the next
* transfer in DMA mode 0, so we never transmit a short packet in
* DMA mode 1.
*
* 05000463 - This anomaly doesn't affect this driver since it
* never uses L1 or L2 memory as data destination.
*
* 05000464 - This anomaly doesn't affect this driver since it
* never uses L1 or L2 memory as data source.
*
* 05000465 - The anomaly can be seen when SCLK is over 100 MHz, and there is
* no way to workaround for bulk endpoints. Since the wMaxPackSize
* of bulk is less than or equal to 512, while the fifo size of
* endpoint 5, 6, 7 is 1024, the double buffer mode is enabled
* automatically when these endpoints are used for bulk OUT.
*
* 05000466 - This anomaly doesn't affect this driver since it never mixes
* concurrent DMA and core accesses to the TX endpoint FIFOs.
*
* 05000467 - The workaround for this anomaly will introduce another
* anomaly - 05000465.
*/
#undef DUMP_FIFO_DATA
#ifdef DUMP_FIFO_DATA
static void dump_fifo_data(u8 *buf, u16 len)
......
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