diff options
Diffstat (limited to 'arch/arm/plat-omap/dma.c')
| -rw-r--r-- | arch/arm/plat-omap/dma.c | 36 |
1 files changed, 34 insertions, 2 deletions
diff --git a/arch/arm/plat-omap/dma.c b/arch/arm/plat-omap/dma.c index 420cef370b33..f5c5b8da9a87 100644 --- a/arch/arm/plat-omap/dma.c +++ b/arch/arm/plat-omap/dma.c @@ -30,6 +30,7 @@ #include <linux/irq.h> #include <linux/io.h> #include <linux/slab.h> +#include <linux/delay.h> #include <asm/system.h> #include <mach/hardware.h> @@ -1024,8 +1025,39 @@ void omap_stop_dma(int lch) dma_write(0, CICR(lch)); l = dma_read(CCR(lch)); - l &= ~OMAP_DMA_CCR_EN; - dma_write(l, CCR(lch)); + /* OMAP3 Errata i541: sDMA FIFO draining does not finish */ + if (cpu_is_omap34xx() && (l & OMAP_DMA_CCR_SEL_SRC_DST_SYNC)) { + int i = 0; + u32 sys_cf; + + /* Configure No-Standby */ + l = dma_read(OCP_SYSCONFIG); + sys_cf = l; + l &= ~DMA_SYSCONFIG_MIDLEMODE_MASK; + l |= DMA_SYSCONFIG_MIDLEMODE(DMA_IDLEMODE_NO_IDLE); + dma_write(l , OCP_SYSCONFIG); + + l = dma_read(CCR(lch)); + l &= ~OMAP_DMA_CCR_EN; + dma_write(l, CCR(lch)); + + /* Wait for sDMA FIFO drain */ + l = dma_read(CCR(lch)); + while (i < 100 && (l & (OMAP_DMA_CCR_RD_ACTIVE | + OMAP_DMA_CCR_WR_ACTIVE))) { + udelay(5); + i++; + l = dma_read(CCR(lch)); + } + if (i >= 100) + printk(KERN_ERR "DMA drain did not complete on " + "lch %d\n", lch); + /* Restore OCP_SYSCONFIG */ + dma_write(sys_cf, OCP_SYSCONFIG); + } else { + l &= ~OMAP_DMA_CCR_EN; + dma_write(l, CCR(lch)); + } if (!omap_dma_in_1510_mode() && dma_chan[lch].next_lch != -1) { int next_lch, cur_lch = lch; |