Blackfin: split cache handling out of dma_memcpy()
authorMike Frysinger <vapier@gentoo.org>
Thu, 7 Aug 2008 19:31:13 +0000 (15:31 -0400)
committerMike Frysinger <vapier@gentoo.org>
Wed, 28 Jan 2009 18:26:10 +0000 (13:26 -0500)
Creating a new dma_memcpy() function that skips all cache checks allows us
to use the function in very early init where the cache is not yet setup.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
lib_blackfin/string.c

index ab71285bb638a796da2638697d9147f0ba4a9477..2a56910affa2632292002594fc8b8b08c74753d0 100644 (file)
@@ -134,7 +134,7 @@ int strncmp(const char *cs, const char *ct, size_t count)
  * Perhaps we should detect that ?  Nowhere do we actually
  * use dma memcpy for those types of lengths though ...
  */
-static void *dma_memcpy(void *dst, const void *src, size_t count)
+void dma_memcpy_nocache(void *dst, const void *src, size_t count)
 {
        /* Scratchpad cannot be a DMA source or destination */
        if (((unsigned long)src >= L1_SRAM_SCRATCH &&
@@ -143,10 +143,9 @@ static void *dma_memcpy(void *dst, const void *src, size_t count)
             (unsigned long)dst < L1_SRAM_SCRATCH_END))
                hang();
 
-       if (dcache_status())
-               blackfin_dcache_flush_range(src, src + count);
-
-       bfin_write_MDMA_D0_IRQ_STATUS(DMA_DONE | DMA_ERR);
+       bfin_write_MDMA_S0_CONFIG(0);
+       bfin_write_MDMA_D0_CONFIG(0);
+       bfin_write_MDMA_D0_IRQ_STATUS(DMA_RUN | DMA_DONE | DMA_ERR);
 
        /* Copy sram functions from sdram to sram */
        /* Setup destination start address */
@@ -165,13 +164,23 @@ static void *dma_memcpy(void *dst, const void *src, size_t count)
 
        /* Enable source DMA */
        bfin_write_MDMA_S0_CONFIG(DMAEN);
-       SSYNC();
 
        bfin_write_MDMA_D0_CONFIG(WNR | DMAEN);
+       SSYNC();
 
        while (bfin_read_MDMA_D0_IRQ_STATUS() & DMA_RUN)
-               bfin_write_MDMA_D0_IRQ_STATUS(bfin_read_MDMA_D0_IRQ_STATUS() | DMA_DONE | DMA_ERR);
-       bfin_write_MDMA_D0_IRQ_STATUS(bfin_read_MDMA_D0_IRQ_STATUS() | DMA_DONE | DMA_ERR);
+               continue;
+
+       bfin_write_MDMA_D0_IRQ_STATUS(bfin_read_MDMA_D0_IRQ_STATUS() | DMA_RUN | DMA_DONE | DMA_ERR);
+       bfin_write_MDMA_D0_CONFIG(0);
+       bfin_write_MDMA_S0_CONFIG(0);
+}
+void *dma_memcpy(void *dst, const void *src, size_t count)
+{
+       if (dcache_status())
+               blackfin_dcache_flush_range(src, src + count);
+
+       dma_memcpy_nocache(dst, src, count);
 
        if (icache_status())
                blackfin_icache_flush_range(dst, dst + count);