From 13d8031dd480b23620923c39400831f7edc68276 Mon Sep 17 00:00:00 2001 From: Robin Gong Date: Thu, 10 May 2018 01:02:01 +0800 Subject: [PATCH] MLK-18248: dma: fsl-edma-v3: avoid touch unused edma channel Avoid touch unused edma channel register in susped/resume, otherwise, kernel crash if XRDC enabled in scfw. Signed-off-by: Robin Gong Acked-by: Fugang Duan (cherry picked from commit aa221c4aba34c6ce1ce5f561fa073bb8297cc0ff) --- drivers/dma/fsl-edma-v3.c | 11 +++++++++++ 1 file changed, 11 insertions(+) --- a/drivers/dma/fsl-edma-v3.c +++ b/drivers/dma/fsl-edma-v3.c @@ -149,6 +149,7 @@ struct fsl_edma3_chan { enum dma_status status; enum fsl_edma3_pm_state pm_state; bool idle; + bool used; struct fsl_edma3_engine *edma3; struct fsl_edma3_desc *edesc; struct fsl_edma3_slave_config fsc; @@ -226,6 +227,8 @@ static void fsl_edma3_enable_request(str val |= EDMA_CH_CSR_ERQ; writel(val, addr + EDMA_CH_CSR); + + fsl_chan->used = true; } static void fsl_edma3_disable_request(struct fsl_edma3_chan *fsl_chan) @@ -281,6 +284,7 @@ static int fsl_edma3_terminate_all(struc fsl_edma3_disable_request(fsl_chan); fsl_chan->edesc = NULL; fsl_chan->idle = true; + fsl_chan->used = false; vchan_get_all_descriptors(&fsl_chan->vchan, &head); spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags); vchan_dma_desc_free_list(&fsl_chan->vchan, &head); @@ -805,6 +809,7 @@ static void fsl_edma3_free_chan_resource vchan_dma_desc_free_list(&fsl_chan->vchan, &head); dma_pool_destroy(fsl_chan->tcd_pool); fsl_chan->tcd_pool = NULL; + fsl_chan->used = false; } static int fsl_edma3_probe(struct platform_device *pdev) @@ -900,6 +905,7 @@ static int fsl_edma3_probe(struct platfo fsl_chan->vchan.desc_free = fsl_edma3_free_desc; vchan_init(&fsl_chan->vchan, &fsl_edma3->dma_dev); + fsl_chan->used = false; } mutex_init(&fsl_edma3->fsl_edma3_mutex); @@ -969,6 +975,8 @@ static int fsl_edma3_suspend_late(struct fsl_chan = &fsl_edma->chans[i]; addr = fsl_chan->membase; + if (!fsl_chan->used) + continue; spin_lock_irqsave(&fsl_chan->vchan.lock, flags); fsl_edma->edma_regs[i].csr = readl(addr + EDMA_CH_CSR); fsl_edma->edma_regs[i].sbr = readl(addr + EDMA_CH_SBR); @@ -996,6 +1004,9 @@ static int fsl_edma3_resume_early(struct fsl_chan = &fsl_edma->chans[i]; addr = fsl_chan->membase; + if (!fsl_chan->used) + continue; + spin_lock_irqsave(&fsl_chan->vchan.lock, flags); writel(fsl_edma->edma_regs[i].csr, addr + EDMA_CH_CSR); writel(fsl_edma->edma_regs[i].sbr, addr + EDMA_CH_SBR);