MLK-11358-4: dma: imx-sdma: save and restore context on i.mx6sx/i.mx7d

Because load context code has been removed in prepare DMA transfer everytime.
Need restore them back once mega/fast powered off.

Signed-off-by: Robin Gong <b38343@freescale.com>

diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index 2ec9411..239d7ee 100644 (file)
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -988,6 +988,31 @@ static int sdma_load_context(struct sdma_channel *sdmac)
        return ret;
 }
 
+static int sdma_save_restore_context(struct sdma_engine *sdma, bool save)
+{
+       struct sdma_context_data *context = sdma->context;
+       struct sdma_buffer_descriptor *bd0 = sdma->channel[0].bd;
+       unsigned long flags;
+       int ret;
+
+       spin_lock_irqsave(&sdma->channel_0_lock, flags);
+
+       if (save)
+               bd0->mode.command = C0_GETDM;
+       else
+               bd0->mode.command = C0_SETDM;
+
+       bd0->mode.status = BD_DONE | BD_INTR | BD_WRAP | BD_EXTD;
+       bd0->mode.count = MAX_DMA_CHANNELS * sizeof(*context) / 4;
+       bd0->buffer_addr = sdma->context_phys;
+       bd0->ext_buffer_addr = 2048;
+       ret = sdma_run_channel0(sdma);
+
+       spin_unlock_irqrestore(&sdma->channel_0_lock, flags);
+
+       return ret;
+}
+
 static struct sdma_channel *to_sdma_chan(struct dma_chan *chan)
 {
        return container_of(chan, struct sdma_channel, chan);
@@ -1833,8 +1858,8 @@ static int sdma_init(struct sdma_engine *sdma)
        /* Be sure SDMA has not started yet */
        writel_relaxed(0, sdma->regs + SDMA_H_C0PTR);
 
-       ccbsize = MAX_DMA_CHANNELS * sizeof (struct sdma_channel_control)
-               + sizeof(struct sdma_context_data);
+       ccbsize = MAX_DMA_CHANNELS * (sizeof(struct sdma_channel_control)
+               + sizeof(struct sdma_context_data));
 
        sdma->channel_control = gen_pool_dma_alloc(sdma->iram_pool, ccbsize, &ccb_phys);
        if (!sdma->channel_control) {
@@ -2149,7 +2174,7 @@ static int sdma_suspend(struct device *dev)
 {
        struct platform_device *pdev = to_platform_device(dev);
        struct sdma_engine *sdma = platform_get_drvdata(pdev);
-       int i;
+       int i, ret = 0;
 
        /* Do nothing if not i.MX6SX or i.MX7D*/
        if (sdma->drvdata != &sdma_imx6sx && sdma->drvdata != &sdma_imx7d)
@@ -2157,6 +2182,12 @@ static int sdma_suspend(struct device *dev)
 
        clk_enable(sdma->clk_ipg);
        clk_enable(sdma->clk_ahb);
+
+       ret = sdma_save_restore_context(sdma, true);
+       if (ret) {
+               dev_err(sdma->dev, "save context error!\n");
+               return ret;
+       }
        /* save regs */
        for (i = 0; i < MXC_SDMA_SAVED_REG_NUM; i++) {
                /*
@@ -2219,6 +2250,12 @@ static int sdma_resume(struct device *dev)
                return ret;
        }
 
+       ret = sdma_save_restore_context(sdma, false);
+       if (ret) {
+               dev_err(sdma->dev, "restore context error!\n");
+               return ret;
+       }
+
        return 0;
 }
 #endif