sata_rcar: kill superfluous code in sata_rcar_bmdma_fill_sg()

I've modified sata_rcar_bmdma_fill_sg() to take care of splitting long
scatter/ gather segments due to the descriptor table transfer counter
being only 28 bits wide (bit 1 to bit 28) but that was in vain as even
if 'sata_rcar_sht' specified a correct 'dma_boundary' field, the DMA
and block layers would have split the S/G segments on the necassary
boundaries. Since the driver uses ATA_BMDMA_SHT() to initilaize
'sata_rcar_sht', the boundary is much smaller, only 0xFFFF, so the
code I've added is even more useless, and it's better to just remove
it.

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

1 files changed, 6 insertions, 18 deletions

diff --git a/drivers/ata/sata_rcar.c b/drivers/ata/sata_rcar.c
index 889c25a6337e..629b07c452c5 100644
--- a/drivers/ata/sata_rcar.c
+++ b/drivers/ata/sata_rcar.c
@@ -474,11 +474,10 @@ static void sata_rcar_bmdma_fill_sg(struct ata_queued_cmd *qc)
         struct ata_port *ap = qc->ap;
         struct ata_bmdma_prd *prd = ap->bmdma_prd;
         struct scatterlist *sg;
-        unsigned int si, pi;
+        unsigned int si;
 
-        pi = 0;
         for_each_sg(qc->sg, sg, qc->n_elem, si) {
-                u32 addr, sg_len, len;
+                u32 addr, sg_len;
 
                 /*
                  * Note: h/w doesn't support 64-bit, so we unconditionally
@@ -487,24 +486,13 @@ static void sata_rcar_bmdma_fill_sg(struct ata_queued_cmd *qc)
                 addr = (u32)sg_dma_address(sg);
                 sg_len = sg_dma_len(sg);
 
-                /* H/w transfer count is only 29 bits long, let's be careful */
-                while (sg_len) {
-                        len = sg_len;
-                        if (len > 0x1ffffffe)
-                                len = 0x1ffffffe;
-
-                        prd[pi].addr = cpu_to_le32(addr);
-                        prd[pi].flags_len = cpu_to_le32(len);
-                        VPRINTK("PRD[%u] = (0x%X, 0x%X)\n", pi, addr, len);
-
-                        pi++;
-                        sg_len -= len;
-                        addr += len;
-                }
+                prd[si].addr = cpu_to_le32(addr);
+                prd[si].flags_len = cpu_to_le32(sg_len);
+                VPRINTK("PRD[%u] = (0x%X, 0x%X)\n", si, addr, sg_len);
         }
 
         /* end-of-table flag */
-        prd[pi - 1].addr |= cpu_to_le32(SATA_RCAR_DTEND);
+        prd[si - 1].addr |= cpu_to_le32(SATA_RCAR_DTEND);
 }
 
 static void sata_rcar_qc_prep(struct ata_queued_cmd *qc)