dmaengine: tegra210-adma: Support dma-channel-mask property

To support the flexibility to reserve the specific dma channels
add the support of dma-channel-mask property in the tegra210-adma
driver

Signed-off-by: Mohan Kumar <mkumard@nvidia.com>
Link: https://lore.kernel.org/r/20231128071615.31447-3-mkumard@nvidia.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

diff --git a/drivers/dma/tegra210-adma.c b/drivers/dma/tegra210-adma.c
index 7a0586633bf32624b442cf5569bacf9361408b78..24ad7077c53ba8f87b7dfb53b1d922a4bec411d2 100644 (file)
--- a/drivers/dma/tegra210-adma.c
+++ b/drivers/dma/tegra210-adma.c
@@ -153,6 +153,7 @@ struct tegra_adma {
        void __iomem                    *base_addr;
        struct clk                      *ahub_clk;
        unsigned int                    nr_channels;
+       unsigned long                   *dma_chan_mask;
        unsigned long                   rx_requests_reserved;
        unsigned long                   tx_requests_reserved;
 
@@ -741,6 +742,10 @@ static int __maybe_unused tegra_adma_runtime_suspend(struct device *dev)
 
        for (i = 0; i < tdma->nr_channels; i++) {
                tdc = &tdma->channels[i];
+               /* skip for reserved channels */
+               if (!tdc->tdma)
+                       continue;
+
                ch_reg = &tdc->ch_regs;
                ch_reg->cmd = tdma_ch_read(tdc, ADMA_CH_CMD);
                /* skip if channel is not active */
@@ -779,6 +784,9 @@ static int __maybe_unused tegra_adma_runtime_resume(struct device *dev)
 
        for (i = 0; i < tdma->nr_channels; i++) {
                tdc = &tdma->channels[i];
+               /* skip for reserved channels */
+               if (!tdc->tdma)
+                       continue;
                ch_reg = &tdc->ch_regs;
                /* skip if channel was not active earlier */
                if (!ch_reg->cmd)
@@ -867,10 +875,31 @@ static int tegra_adma_probe(struct platform_device *pdev)
                return PTR_ERR(tdma->ahub_clk);
        }
 
+       tdma->dma_chan_mask = devm_kzalloc(&pdev->dev,
+                                          BITS_TO_LONGS(tdma->nr_channels) * sizeof(unsigned long),
+                                          GFP_KERNEL);
+       if (!tdma->dma_chan_mask)
+               return -ENOMEM;
+
+       /* Enable all channels by default */
+       bitmap_fill(tdma->dma_chan_mask, tdma->nr_channels);
+
+       ret = of_property_read_u32_array(pdev->dev.of_node, "dma-channel-mask",
+                                        (u32 *)tdma->dma_chan_mask,
+                                        BITS_TO_U32(tdma->nr_channels));
+       if (ret < 0 && (ret != -EINVAL)) {
+               dev_err(&pdev->dev, "dma-channel-mask is not complete.\n");
+               return ret;
+       }
+
        INIT_LIST_HEAD(&tdma->dma_dev.channels);
        for (i = 0; i < tdma->nr_channels; i++) {
                struct tegra_adma_chan *tdc = &tdma->channels[i];
 
+               /* skip for reserved channels */
+               if (!test_bit(i, tdma->dma_chan_mask))
+                       continue;
+
                tdc->chan_addr = tdma->base_addr + cdata->ch_base_offset
                                 + (cdata->ch_reg_size * i);
 
@@ -957,8 +986,10 @@ static void tegra_adma_remove(struct platform_device *pdev)
        of_dma_controller_free(pdev->dev.of_node);
        dma_async_device_unregister(&tdma->dma_dev);
 
-       for (i = 0; i < tdma->nr_channels; ++i)
-               irq_dispose_mapping(tdma->channels[i].irq);
+       for (i = 0; i < tdma->nr_channels; ++i) {
+               if (tdma->channels[i].irq)
+                       irq_dispose_mapping(tdma->channels[i].irq);
+       }
 
        pm_runtime_disable(&pdev->dev);
 }