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author | Steven Miao <realmz6@gmail.com> | 2011-05-05 14:14:48 +0800 |
---|---|---|
committer | Mike Frysinger <vapier@gentoo.org> | 2011-05-25 08:24:14 -0400 |
commit | f9691bb9674b6822ace56370a08c6fc02addf6cb (patch) | |
tree | 40f9f39d38326c498ea5f3d63cd2c1e059b8bf21 | |
parent | 7a7a430f7498cd55820232d8e3f144161138f91a (diff) | |
download | blackbird-op-linux-f9691bb9674b6822ace56370a08c6fc02addf6cb.tar.gz blackbird-op-linux-f9691bb9674b6822ace56370a08c6fc02addf6cb.zip |
Blackfin: work around anomaly 05000480
Anomaly 05000480 on BF537 rev 0.0, 0.1, 0.2:
Multiple Simultaneous Urgent DMA Requests May Cause DMA System Instability
Suggested Workaround:
Program the DMA Traffic Control Period to a non-zero value. This forces
the DMA block to group accesses together rather than allow arbitration for
each piece of data placed on the internal DMA bus.
Signed-off-by: Steven Miao <realmz6@gmail.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
-rw-r--r-- | arch/blackfin/kernel/bfin_dma_5xx.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/arch/blackfin/kernel/bfin_dma_5xx.c b/arch/blackfin/kernel/bfin_dma_5xx.c index 6ce8dce753c9..71dbaa4a48af 100644 --- a/arch/blackfin/kernel/bfin_dma_5xx.c +++ b/arch/blackfin/kernel/bfin_dma_5xx.c @@ -36,6 +36,11 @@ static int __init blackfin_dma_init(void) printk(KERN_INFO "Blackfin DMA Controller\n"); + +#if ANOMALY_05000480 + bfin_write_DMAC_TC_PER(0x0111); +#endif + for (i = 0; i < MAX_DMA_CHANNELS; i++) { atomic_set(&dma_ch[i].chan_status, 0); dma_ch[i].regs = dma_io_base_addr[i]; |