target/linux/layerscape/patches-5.4/806-dma-0014-MLK-18248-dma-fsl-edma-v3-avoid-touch-unused-edma-ch.patch

   1 From 13d8031dd480b23620923c39400831f7edc68276 Mon Sep 17 00:00:00 2001
   2 From: Robin Gong <yibin.gong@nxp.com>
   3 Date: Thu, 10 May 2018 01:02:01 +0800
   4 Subject: [PATCH] MLK-18248: dma: fsl-edma-v3: avoid touch unused edma channel
   5
   6 Avoid touch unused edma channel register in susped/resume, otherwise,
   7 kernel crash if XRDC enabled in scfw.
   8
   9 Signed-off-by: Robin Gong <yibin.gong@nxp.com>
  10 Acked-by: Fugang Duan <fugang.duan@nxp.com>
  11 (cherry picked from commit aa221c4aba34c6ce1ce5f561fa073bb8297cc0ff)
  12 ---
  13  drivers/dma/fsl-edma-v3.c | 11 +++++++++++
  14  1 file changed, 11 insertions(+)
  15
  16 --- a/drivers/dma/fsl-edma-v3.c
  17 +++ b/drivers/dma/fsl-edma-v3.c
  18 @@ -149,6 +149,7 @@ struct fsl_edma3_chan {
  19         enum dma_status                 status;
  20         enum fsl_edma3_pm_state         pm_state;
  21         bool                            idle;
  22 +       bool                            used;
  23         struct fsl_edma3_engine         *edma3;
  24         struct fsl_edma3_desc           *edesc;
  25         struct fsl_edma3_slave_config   fsc;
  26 @@ -226,6 +227,8 @@ static void fsl_edma3_enable_request(str
  27
  28         val |= EDMA_CH_CSR_ERQ;
  29         writel(val, addr + EDMA_CH_CSR);
  30 +
  31 +       fsl_chan->used = true;
  32  }
  33
  34  static void fsl_edma3_disable_request(struct fsl_edma3_chan *fsl_chan)
  35 @@ -281,6 +284,7 @@ static int fsl_edma3_terminate_all(struc
  36         fsl_edma3_disable_request(fsl_chan);
  37         fsl_chan->edesc = NULL;
  38         fsl_chan->idle = true;
  39 +       fsl_chan->used = false;
  40         vchan_get_all_descriptors(&fsl_chan->vchan, &head);
  41         spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
  42         vchan_dma_desc_free_list(&fsl_chan->vchan, &head);
  43 @@ -805,6 +809,7 @@ static void fsl_edma3_free_chan_resource
  44         vchan_dma_desc_free_list(&fsl_chan->vchan, &head);
  45         dma_pool_destroy(fsl_chan->tcd_pool);
  46         fsl_chan->tcd_pool = NULL;
  47 +       fsl_chan->used = false;
  48  }
  49
  50  static int fsl_edma3_probe(struct platform_device *pdev)
  51 @@ -900,6 +905,7 @@ static int fsl_edma3_probe(struct platfo
  52
  53                 fsl_chan->vchan.desc_free = fsl_edma3_free_desc;
  54                 vchan_init(&fsl_chan->vchan, &fsl_edma3->dma_dev);
  55 +               fsl_chan->used = false;
  56         }
  57
  58         mutex_init(&fsl_edma3->fsl_edma3_mutex);
  59 @@ -969,6 +975,8 @@ static int fsl_edma3_suspend_late(struct
  60                 fsl_chan = &fsl_edma->chans[i];
  61                 addr = fsl_chan->membase;
  62
  63 +               if (!fsl_chan->used)
  64 +                       continue;
  65                 spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
  66                 fsl_edma->edma_regs[i].csr = readl(addr + EDMA_CH_CSR);
  67                 fsl_edma->edma_regs[i].sbr = readl(addr + EDMA_CH_SBR);
  68 @@ -996,6 +1004,9 @@ static int fsl_edma3_resume_early(struct
  69                 fsl_chan = &fsl_edma->chans[i];
  70                 addr = fsl_chan->membase;
  71
  72 +               if (!fsl_chan->used)
  73 +                       continue;
  74 +
  75                 spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
  76                 writel(fsl_edma->edma_regs[i].csr, addr + EDMA_CH_CSR);
  77                 writel(fsl_edma->edma_regs[i].sbr, addr + EDMA_CH_SBR);