[coreboot-gerrit] New patch to review for coreboot: t210: Correct dma_busy function

[Patrick Georgi (pgeorgi@google.com)]

Patrick Georgi (pgeorgi at google.com) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/10946

-gerrit

commit 22f574f24111ff42e20d863313e6fe4bc193464d
Author: Furquan Shaikh <furquan at google.com>
Date:   Mon Jul 13 09:48:52 2015 -0700

    t210: Correct dma_busy function
    
    In case of continuous mode, use STA_ACTIVITY bit to determine if DMA
    operation is complete. However, in case of ONCE mode, use STA_BSY bit
    to determine if DMA operation on the channel is complete.
    
    BUG=chrome-os-partner:41877
    BRANCH=None
    TEST=Compiles successfully and reboot test runs fine for 10K+ iterations
    
    Change-Id: If98f195481b18c402bd9cac353080c317e0e1168
    Signed-off-by: Patrick Georgi <pgeorgi at chromium.org>
    Original-Commit-Id: 927026db6fd910dac32dc218f28efcbc7b788b4e
    Original-Change-Id: Ib66bedfb413f948728a4f9cffce9d9c3feb0bfda
    Original-Signed-off-by: Furquan Shaikh <furquan at google.com>
    Original-Reviewed-on: https://chromium-review.googlesource.com/285140
    Original-Tested-by: Furquan Shaikh <furquan at chromium.org>
    Original-Reviewed-by: Aaron Durbin <adurbin at chromium.org>
    Original-Commit-Queue: Furquan Shaikh <furquan at chromium.org>
    Original-Trybot-Ready: Furquan Shaikh <furquan at chromium.org>
---
 src/soc/nvidia/tegra210/dma.c | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/src/soc/nvidia/tegra210/dma.c b/src/soc/nvidia/tegra210/dma.c
index 9f04e97..fb98692 100644
--- a/src/soc/nvidia/tegra210/dma.c
+++ b/src/soc/nvidia/tegra210/dma.c
@@ -69,9 +69,21 @@ int dma_busy(struct apb_dma_channel * const channel)
 	 * In continuous mode, the BSY_n bit in APB_DMA_STATUS and
 	 * BSY in APBDMACHAN_CHANNEL_n_STA_0 will remain set as '1' so long
 	 * as the channel is enabled. So for this function we'll use the
-	 * DMA_ACTIVITY bit.
+	 * DMA_ACTIVITY bit in case of continuous mode.
+	 *
+	 * However, for ONCE mode, the BSY_n bit in APB_DMA_STATUS will be used
+	 * to determine end of dma operation.
 	 */
-	return read32(&channel->regs->sta) & APB_STA_DMA_ACTIVITY ? 1 : 0;
+	uint32_t bit;
+
+	if (read32(&channel->regs->csr) & APB_CSR_ONCE)
+		/* Once mode */
+		bit = APB_STA_BSY;
+	else
+		/* Continuous mode */
+		bit = APB_STA_DMA_ACTIVITY;
+
+	return read32(&channel->regs->sta) & bit ? 1 : 0;
 }
 /* claim a DMA channel */
 struct apb_dma_channel * const dma_claim(void)