Hi Angelo, On 18.01.2019 23:50, Angelo Dureghello wrote: > Hi Laurentiu, > > On Fri, Jan 18, 2019 at 12:06:23PM +0200, Laurentiu Tudor wrote: >> This mapping needs to be created in order for slave dma transfers >> to work on systems with SMMU. The implementation mostly mimics the >> one in pl330 dma driver, authored by Robin Murphy. >> >> Signed-off-by: Laurentiu Tudor <laurentiu.tudor@xxxxxxx> >> Suggested-by: Robin Murphy <robin.murphy@xxxxxxx> >> --- >> Original approach was to add the missing mappings in the i2c client driver, >> see here for discussion: https://emea01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fpatchwork.ozlabs.org%2Fpatch%2F1026013%2F&data=02%7C01%7Claurentiu.tudor%40nxp.com%7C7861dfe95dfb4fceeb8208d67d907488%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C1%7C636834456718898365&sdata=XM5shQdcIRgFLtCmuRuFtViR6ttPDWI%2BNHXoPi68Xs8%3D&reserved=0 >> >> drivers/dma/fsl-edma-common.c | 66 ++++++++++++++++++++++++++++++++--- >> drivers/dma/fsl-edma-common.h | 4 +++ >> drivers/dma/fsl-edma.c | 1 + >> drivers/dma/mcf-edma.c | 1 + >> 4 files changed, 68 insertions(+), 4 deletions(-) >> >> diff --git a/drivers/dma/fsl-edma-common.c b/drivers/dma/fsl-edma-common.c >> index 8876c4c1bb2c..0e95ee24b6d4 100644 >> --- a/drivers/dma/fsl-edma-common.c >> +++ b/drivers/dma/fsl-edma-common.c >> @@ -6,6 +6,7 @@ >> #include <linux/dmapool.h> >> #include <linux/module.h> >> #include <linux/slab.h> >> +#include <linux/dma-mapping.h> >> >> #include "fsl-edma-common.h" >> >> @@ -173,12 +174,62 @@ int fsl_edma_resume(struct dma_chan *chan) >> } >> EXPORT_SYMBOL_GPL(fsl_edma_resume); >> >> +static void fsl_edma_unprep_slave_dma(struct fsl_edma_chan *fsl_chan) >> +{ >> + if (fsl_chan->dma_dir != DMA_NONE) >> + dma_unmap_resource(fsl_chan->vchan.chan.device->dev, >> + fsl_chan->dma_dev_addr, >> + fsl_chan->dma_dev_size, >> + fsl_chan->dma_dir, 0); >> + fsl_chan->dma_dir = DMA_NONE; >> +} >> + >> +static bool fsl_edma_prep_slave_dma(struct fsl_edma_chan *fsl_chan, >> + enum dma_transfer_direction dir) >> +{ >> + struct device *dev = fsl_chan->vchan.chan.device->dev; >> + enum dma_data_direction dma_dir; >> + phys_addr_t addr = 0; >> + u32 size = 0; >> + >> + switch (dir) { >> + case DMA_MEM_TO_DEV: >> + dma_dir = DMA_FROM_DEVICE; >> + addr = fsl_chan->cfg.dst_addr; >> + size = fsl_chan->cfg.dst_maxburst; >> + break; >> + case DMA_DEV_TO_MEM: >> + dma_dir = DMA_TO_DEVICE; >> + addr = fsl_chan->cfg.src_addr; >> + size = fsl_chan->cfg.src_maxburst; >> + break; >> + default: >> + dma_dir = DMA_NONE; >> + break; >> + } >> + >> + /* Already mapped for this config? */ >> + if (fsl_chan->dma_dir == dma_dir) >> + return true; >> + >> + fsl_edma_unprep_slave_dma(fsl_chan); >> + >> + fsl_chan->dma_dev_addr = dma_map_resource(dev, addr, size, dma_dir, 0); >> + if (dma_mapping_error(dev, fsl_chan->dma_dev_addr)) >> + return false; >> + fsl_chan->dma_dev_size = size; >> + fsl_chan->dma_dir = dma_dir; >> + >> + return true; >> +} >> + >> int fsl_edma_slave_config(struct dma_chan *chan, >> struct dma_slave_config *cfg) >> { >> struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan); >> >> memcpy(&fsl_chan->cfg, cfg, sizeof(*cfg)); >> + fsl_edma_unprep_slave_dma(fsl_chan); >> >> return 0; >> } >> @@ -378,6 +429,9 @@ struct dma_async_tx_descriptor *fsl_edma_prep_dma_cyclic( >> if (!is_slave_direction(direction)) >> return NULL; >> >> + if (!fsl_edma_prep_slave_dma(fsl_chan, direction)) >> + return NULL; >> + >> sg_len = buf_len / period_len; >> fsl_desc = fsl_edma_alloc_desc(fsl_chan, sg_len); >> if (!fsl_desc) >> @@ -409,11 +463,11 @@ struct dma_async_tx_descriptor *fsl_edma_prep_dma_cyclic( >> >> if (direction == DMA_MEM_TO_DEV) { >> src_addr = dma_buf_next; >> - dst_addr = fsl_chan->cfg.dst_addr; >> + dst_addr = fsl_chan->dma_dev_addr; >> soff = fsl_chan->cfg.dst_addr_width; >> doff = 0; >> } else { >> - src_addr = fsl_chan->cfg.src_addr; >> + src_addr = fsl_chan->dma_dev_addr; >> dst_addr = dma_buf_next; >> soff = 0; >> doff = fsl_chan->cfg.src_addr_width; >> @@ -444,6 +498,9 @@ struct dma_async_tx_descriptor *fsl_edma_prep_slave_sg( >> if (!is_slave_direction(direction)) >> return NULL; >> >> + if (!fsl_edma_prep_slave_dma(fsl_chan, direction)) >> + return NULL; >> + >> fsl_desc = fsl_edma_alloc_desc(fsl_chan, sg_len); >> if (!fsl_desc) >> return NULL; >> @@ -468,11 +525,11 @@ struct dma_async_tx_descriptor *fsl_edma_prep_slave_sg( >> >> if (direction == DMA_MEM_TO_DEV) { >> src_addr = sg_dma_address(sg); >> - dst_addr = fsl_chan->cfg.dst_addr; >> + dst_addr = fsl_chan->dma_dev_addr; >> soff = fsl_chan->cfg.dst_addr_width; >> doff = 0; >> } else { >> - src_addr = fsl_chan->cfg.src_addr; >> + src_addr = fsl_chan->dma_dev_addr; >> dst_addr = sg_dma_address(sg); >> soff = 0; >> doff = fsl_chan->cfg.src_addr_width; >> @@ -555,6 +612,7 @@ void fsl_edma_free_chan_resources(struct dma_chan *chan) >> fsl_edma_chan_mux(fsl_chan, 0, false); >> fsl_chan->edesc = NULL; >> vchan_get_all_descriptors(&fsl_chan->vchan, &head); >> + fsl_edma_unprep_slave_dma(fsl_chan); >> spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags); >> >> vchan_dma_desc_free_list(&fsl_chan->vchan, &head); >> diff --git a/drivers/dma/fsl-edma-common.h b/drivers/dma/fsl-edma-common.h >> index 8917e8865959..b435d8e1e3a1 100644 >> --- a/drivers/dma/fsl-edma-common.h >> +++ b/drivers/dma/fsl-edma-common.h >> @@ -6,6 +6,7 @@ >> #ifndef _FSL_EDMA_COMMON_H_ >> #define _FSL_EDMA_COMMON_H_ >> >> +#include <linux/dma-direction.h> >> #include "virt-dma.h" >> >> #define EDMA_CR_EDBG BIT(1) >> @@ -120,6 +121,9 @@ struct fsl_edma_chan { >> struct dma_slave_config cfg; >> u32 attr; >> struct dma_pool *tcd_pool; >> + dma_addr_t dma_dev_addr; >> + u32 dma_dev_size; >> + enum dma_data_direction dma_dir; >> }; >> >> struct fsl_edma_desc { >> diff --git a/drivers/dma/fsl-edma.c b/drivers/dma/fsl-edma.c >> index 34d70112fcc9..75e8a7ba3a22 100644 >> --- a/drivers/dma/fsl-edma.c >> +++ b/drivers/dma/fsl-edma.c >> @@ -254,6 +254,7 @@ static int fsl_edma_probe(struct platform_device *pdev) >> fsl_chan->pm_state = RUNNING; >> fsl_chan->slave_id = 0; >> fsl_chan->idle = true; >> + fsl_chan->dma_dir = DMA_NONE; >> fsl_chan->vchan.desc_free = fsl_edma_free_desc; >> vchan_init(&fsl_chan->vchan, &fsl_edma->dma_dev); >> >> diff --git a/drivers/dma/mcf-edma.c b/drivers/dma/mcf-edma.c >> index 5de1b07eddff..7de54b2fafdb 100644 >> --- a/drivers/dma/mcf-edma.c >> +++ b/drivers/dma/mcf-edma.c >> @@ -214,6 +214,7 @@ static int mcf_edma_probe(struct platform_device *pdev) >> mcf_chan->edma = mcf_edma; >> mcf_chan->slave_id = i; >> mcf_chan->idle = true; >> + mcf_chan->dma_dir = DMA_NONE; >> mcf_chan->vchan.desc_free = fsl_edma_free_desc; >> vchan_init(&mcf_chan->vchan, &mcf_edma->dma_dev); >> iowrite32(0x0, ®s->tcd[i].csr); >> -- >> 2.17.1 >> > > I tested this patch on: > > - Vybrid VF50N (Toradex Colibri VF50) > - ColdFire mcf54415 (Sysam stmark2 board) > > and dma still works properly. > > Tested-by: Angelo Dureghello <angelo@xxxxxxxx> > Thanks a lot for testing! --- Best Regards, Laurentiu
