Merge tag 'hsi-for-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-hsi
[firefly-linux-kernel-4.4.55.git] / drivers / dma / at_xdmac.c
index 0dcc9a7a90af66310984ca9832cd22c56bb49d6d..7992164ea9ec2849f6ac3691629c47cda30aeb28 100644 (file)
 #define AT_XDMAC_MBR_UBC_NDV3          (0x3 << 27)     /* Next Descriptor View 3 */
 
 #define AT_XDMAC_MAX_CHAN      0x20
+#define AT_XDMAC_MAX_CSIZE     16      /* 16 data */
+#define AT_XDMAC_MAX_DWIDTH    8       /* 64 bits */
 
 #define AT_XDMAC_DMA_BUSWIDTHS\
        (BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED) |\
@@ -192,20 +194,17 @@ struct at_xdmac_chan {
        struct dma_chan                 chan;
        void __iomem                    *ch_regs;
        u32                             mask;           /* Channel Mask */
-       u32                             cfg[2];         /* Channel Configuration Register */
-       #define AT_XDMAC_DEV_TO_MEM_CFG 0               /* Predifined dev to mem channel conf */
-       #define AT_XDMAC_MEM_TO_DEV_CFG 1               /* Predifined mem to dev channel conf */
+       u32                             cfg;            /* Channel Configuration Register */
        u8                              perid;          /* Peripheral ID */
        u8                              perif;          /* Peripheral Interface */
        u8                              memif;          /* Memory Interface */
-       u32                             per_src_addr;
-       u32                             per_dst_addr;
        u32                             save_cc;
        u32                             save_cim;
        u32                             save_cnda;
        u32                             save_cndc;
        unsigned long                   status;
        struct tasklet_struct           tasklet;
+       struct dma_slave_config         sconfig;
 
        spinlock_t                      lock;
 
@@ -495,61 +494,94 @@ static struct dma_chan *at_xdmac_xlate(struct of_phandle_args *dma_spec,
        return chan;
 }
 
+static int at_xdmac_compute_chan_conf(struct dma_chan *chan,
+                                     enum dma_transfer_direction direction)
+{
+       struct at_xdmac_chan    *atchan = to_at_xdmac_chan(chan);
+       int                     csize, dwidth;
+
+       if (direction == DMA_DEV_TO_MEM) {
+               atchan->cfg =
+                       AT91_XDMAC_DT_PERID(atchan->perid)
+                       | AT_XDMAC_CC_DAM_INCREMENTED_AM
+                       | AT_XDMAC_CC_SAM_FIXED_AM
+                       | AT_XDMAC_CC_DIF(atchan->memif)
+                       | AT_XDMAC_CC_SIF(atchan->perif)
+                       | AT_XDMAC_CC_SWREQ_HWR_CONNECTED
+                       | AT_XDMAC_CC_DSYNC_PER2MEM
+                       | AT_XDMAC_CC_MBSIZE_SIXTEEN
+                       | AT_XDMAC_CC_TYPE_PER_TRAN;
+               csize = ffs(atchan->sconfig.src_maxburst) - 1;
+               if (csize < 0) {
+                       dev_err(chan2dev(chan), "invalid src maxburst value\n");
+                       return -EINVAL;
+               }
+               atchan->cfg |= AT_XDMAC_CC_CSIZE(csize);
+               dwidth = ffs(atchan->sconfig.src_addr_width) - 1;
+               if (dwidth < 0) {
+                       dev_err(chan2dev(chan), "invalid src addr width value\n");
+                       return -EINVAL;
+               }
+               atchan->cfg |= AT_XDMAC_CC_DWIDTH(dwidth);
+       } else if (direction == DMA_MEM_TO_DEV) {
+               atchan->cfg =
+                       AT91_XDMAC_DT_PERID(atchan->perid)
+                       | AT_XDMAC_CC_DAM_FIXED_AM
+                       | AT_XDMAC_CC_SAM_INCREMENTED_AM
+                       | AT_XDMAC_CC_DIF(atchan->perif)
+                       | AT_XDMAC_CC_SIF(atchan->memif)
+                       | AT_XDMAC_CC_SWREQ_HWR_CONNECTED
+                       | AT_XDMAC_CC_DSYNC_MEM2PER
+                       | AT_XDMAC_CC_MBSIZE_SIXTEEN
+                       | AT_XDMAC_CC_TYPE_PER_TRAN;
+               csize = ffs(atchan->sconfig.dst_maxburst) - 1;
+               if (csize < 0) {
+                       dev_err(chan2dev(chan), "invalid src maxburst value\n");
+                       return -EINVAL;
+               }
+               atchan->cfg |= AT_XDMAC_CC_CSIZE(csize);
+               dwidth = ffs(atchan->sconfig.dst_addr_width) - 1;
+               if (dwidth < 0) {
+                       dev_err(chan2dev(chan), "invalid dst addr width value\n");
+                       return -EINVAL;
+               }
+               atchan->cfg |= AT_XDMAC_CC_DWIDTH(dwidth);
+       }
+
+       dev_dbg(chan2dev(chan), "%s: cfg=0x%08x\n", __func__, atchan->cfg);
+
+       return 0;
+}
+
+/*
+ * Only check that maxburst and addr width values are supported by the
+ * the controller but not that the configuration is good to perform the
+ * transfer since we don't know the direction at this stage.
+ */
+static int at_xdmac_check_slave_config(struct dma_slave_config *sconfig)
+{
+       if ((sconfig->src_maxburst > AT_XDMAC_MAX_CSIZE)
+           || (sconfig->dst_maxburst > AT_XDMAC_MAX_CSIZE))
+               return -EINVAL;
+
+       if ((sconfig->src_addr_width > AT_XDMAC_MAX_DWIDTH)
+           || (sconfig->dst_addr_width > AT_XDMAC_MAX_DWIDTH))
+               return -EINVAL;
+
+       return 0;
+}
+
 static int at_xdmac_set_slave_config(struct dma_chan *chan,
                                      struct dma_slave_config *sconfig)
 {
        struct at_xdmac_chan    *atchan = to_at_xdmac_chan(chan);
-       u8 dwidth;
-       int csize;
 
-       atchan->cfg[AT_XDMAC_DEV_TO_MEM_CFG] =
-               AT91_XDMAC_DT_PERID(atchan->perid)
-               | AT_XDMAC_CC_DAM_INCREMENTED_AM
-               | AT_XDMAC_CC_SAM_FIXED_AM
-               | AT_XDMAC_CC_DIF(atchan->memif)
-               | AT_XDMAC_CC_SIF(atchan->perif)
-               | AT_XDMAC_CC_SWREQ_HWR_CONNECTED
-               | AT_XDMAC_CC_DSYNC_PER2MEM
-               | AT_XDMAC_CC_MBSIZE_SIXTEEN
-               | AT_XDMAC_CC_TYPE_PER_TRAN;
-       csize = at_xdmac_csize(sconfig->src_maxburst);
-       if (csize < 0) {
-               dev_err(chan2dev(chan), "invalid src maxburst value\n");
+       if (at_xdmac_check_slave_config(sconfig)) {
+               dev_err(chan2dev(chan), "invalid slave configuration\n");
                return -EINVAL;
        }
-       atchan->cfg[AT_XDMAC_DEV_TO_MEM_CFG] |= AT_XDMAC_CC_CSIZE(csize);
-       dwidth = ffs(sconfig->src_addr_width) - 1;
-       atchan->cfg[AT_XDMAC_DEV_TO_MEM_CFG] |= AT_XDMAC_CC_DWIDTH(dwidth);
-
-
-       atchan->cfg[AT_XDMAC_MEM_TO_DEV_CFG] =
-               AT91_XDMAC_DT_PERID(atchan->perid)
-               | AT_XDMAC_CC_DAM_FIXED_AM
-               | AT_XDMAC_CC_SAM_INCREMENTED_AM
-               | AT_XDMAC_CC_DIF(atchan->perif)
-               | AT_XDMAC_CC_SIF(atchan->memif)
-               | AT_XDMAC_CC_SWREQ_HWR_CONNECTED
-               | AT_XDMAC_CC_DSYNC_MEM2PER
-               | AT_XDMAC_CC_MBSIZE_SIXTEEN
-               | AT_XDMAC_CC_TYPE_PER_TRAN;
-       csize = at_xdmac_csize(sconfig->dst_maxburst);
-       if (csize < 0) {
-               dev_err(chan2dev(chan), "invalid src maxburst value\n");
-               return -EINVAL;
-       }
-       atchan->cfg[AT_XDMAC_MEM_TO_DEV_CFG] |= AT_XDMAC_CC_CSIZE(csize);
-       dwidth = ffs(sconfig->dst_addr_width) - 1;
-       atchan->cfg[AT_XDMAC_MEM_TO_DEV_CFG] |= AT_XDMAC_CC_DWIDTH(dwidth);
-
-       /* Src and dst addr are needed to configure the link list descriptor. */
-       atchan->per_src_addr = sconfig->src_addr;
-       atchan->per_dst_addr = sconfig->dst_addr;
 
-       dev_dbg(chan2dev(chan),
-               "%s: cfg[dev2mem]=0x%08x, cfg[mem2dev]=0x%08x, per_src_addr=0x%08x, per_dst_addr=0x%08x\n",
-               __func__, atchan->cfg[AT_XDMAC_DEV_TO_MEM_CFG],
-               atchan->cfg[AT_XDMAC_MEM_TO_DEV_CFG],
-               atchan->per_src_addr, atchan->per_dst_addr);
+       memcpy(&atchan->sconfig, sconfig, sizeof(atchan->sconfig));
 
        return 0;
 }
@@ -583,6 +615,9 @@ at_xdmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
        /* Protect dma_sconfig field that can be modified by set_slave_conf. */
        spin_lock_irqsave(&atchan->lock, irqflags);
 
+       if (at_xdmac_compute_chan_conf(chan, direction))
+               goto spin_unlock;
+
        /* Prepare descriptors. */
        for_each_sg(sgl, sg, sg_len, i) {
                struct at_xdmac_desc    *desc = NULL;
@@ -607,14 +642,13 @@ at_xdmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
 
                /* Linked list descriptor setup. */
                if (direction == DMA_DEV_TO_MEM) {
-                       desc->lld.mbr_sa = atchan->per_src_addr;
+                       desc->lld.mbr_sa = atchan->sconfig.src_addr;
                        desc->lld.mbr_da = mem;
-                       desc->lld.mbr_cfg = atchan->cfg[AT_XDMAC_DEV_TO_MEM_CFG];
                } else {
                        desc->lld.mbr_sa = mem;
-                       desc->lld.mbr_da = atchan->per_dst_addr;
-                       desc->lld.mbr_cfg = atchan->cfg[AT_XDMAC_MEM_TO_DEV_CFG];
+                       desc->lld.mbr_da = atchan->sconfig.dst_addr;
                }
+               desc->lld.mbr_cfg = atchan->cfg;
                dwidth = at_xdmac_get_dwidth(desc->lld.mbr_cfg);
                fixed_dwidth = IS_ALIGNED(len, 1 << dwidth)
                               ? at_xdmac_get_dwidth(desc->lld.mbr_cfg)
@@ -683,6 +717,9 @@ at_xdmac_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr,
                return NULL;
        }
 
+       if (at_xdmac_compute_chan_conf(chan, direction))
+               return NULL;
+
        for (i = 0; i < periods; i++) {
                struct at_xdmac_desc    *desc = NULL;
 
@@ -701,14 +738,13 @@ at_xdmac_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr,
                        __func__, desc, &desc->tx_dma_desc.phys);
 
                if (direction == DMA_DEV_TO_MEM) {
-                       desc->lld.mbr_sa = atchan->per_src_addr;
+                       desc->lld.mbr_sa = atchan->sconfig.src_addr;
                        desc->lld.mbr_da = buf_addr + i * period_len;
-                       desc->lld.mbr_cfg = atchan->cfg[AT_XDMAC_DEV_TO_MEM_CFG];
                } else {
                        desc->lld.mbr_sa = buf_addr + i * period_len;
-                       desc->lld.mbr_da = atchan->per_dst_addr;
-                       desc->lld.mbr_cfg = atchan->cfg[AT_XDMAC_MEM_TO_DEV_CFG];
+                       desc->lld.mbr_da = atchan->sconfig.dst_addr;
                }
+               desc->lld.mbr_cfg = atchan->cfg;
                desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV1
                        | AT_XDMAC_MBR_UBC_NDEN
                        | AT_XDMAC_MBR_UBC_NSEN