net: stmmac: fixed the pbl setting with DT

This patch fixed the pbl(programmable burst length) setting
using DT. Even though the default pbl is 8, If there is no
pbl property in device tree file, pbl is set 0 and it causes
bandwidth degradation.

Signed-off-by: Byungho An <bh74.an@samsung.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
index 03de76c7a177b6c9b54d571370e92d697c9a9ef6..1c83a44c547b7f1612b748b6c640832fc5f51e66 100644 (file)
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
@@ -71,14 +71,18 @@ static int stmmac_probe_config_dt(struct platform_device *pdev,
                plat->force_sf_dma_mode = 1;
        }
 
-       dma_cfg = devm_kzalloc(&pdev->dev, sizeof(*dma_cfg), GFP_KERNEL);
-       if (!dma_cfg)
-               return -ENOMEM;
-
-       plat->dma_cfg = dma_cfg;
-       of_property_read_u32(np, "snps,pbl", &dma_cfg->pbl);
-       dma_cfg->fixed_burst = of_property_read_bool(np, "snps,fixed-burst");
-       dma_cfg->mixed_burst = of_property_read_bool(np, "snps,mixed-burst");
+       if (of_find_property(np, "snps,pbl", NULL)) {
+               dma_cfg = devm_kzalloc(&pdev->dev, sizeof(*dma_cfg),
+                                      GFP_KERNEL);
+               if (!dma_cfg)
+                       return -ENOMEM;
+               plat->dma_cfg = dma_cfg;
+               of_property_read_u32(np, "snps,pbl", &dma_cfg->pbl);
+               dma_cfg->fixed_burst =
+                       of_property_read_bool(np, "snps,fixed-burst");
+               dma_cfg->mixed_burst =
+                       of_property_read_bool(np, "snps,mixed-burst");
+       }
 
        return 0;
 }