@@ -218,11 +218,18 @@ static void dwmac1000_dump_dma_regs(void __iomem *ioaddr, u32 *reg_space)
readl(ioaddr + DMA_BUS_MODE + i * 4);
}
-static void dwmac1000_get_hw_feature(void __iomem *ioaddr,
- struct dma_features *dma_cap)
+static int dwmac1000_get_hw_feature(void __iomem *ioaddr,
+ struct dma_features *dma_cap)
{
u32 hw_cap = readl(ioaddr + DMA_HW_FEATURE);
+ if (!hw_cap) {
+ /* 0x00000000 is the value read on old hardware that does not
+ * implement this register
+ */
+ return -EOPNOTSUPP;
+ }
+
dma_cap->mbps_10_100 = (hw_cap & DMA_HW_FEAT_MIISEL);
dma_cap->mbps_1000 = (hw_cap & DMA_HW_FEAT_GMIISEL) >> 1;
dma_cap->half_duplex = (hw_cap & DMA_HW_FEAT_HDSEL) >> 2;
@@ -252,6 +259,8 @@ static void dwmac1000_get_hw_feature(void __iomem *ioaddr,
dma_cap->number_tx_channel = (hw_cap & DMA_HW_FEAT_TXCHCNT) >> 22;
/* Alternate (enhanced) DESC mode */
dma_cap->enh_desc = (hw_cap & DMA_HW_FEAT_ENHDESSEL) >> 24;
+
+ return 0;
}
static void dwmac1000_rx_watchdog(void __iomem *ioaddr, u32 riwt,
@@ -347,8 +347,8 @@ static void dwmac4_dma_tx_chan_op_mode(void __iomem *ioaddr, int mode,
writel(mtl_tx_op, ioaddr + MTL_CHAN_TX_OP_MODE(channel));
}
-static void dwmac4_get_hw_feature(void __iomem *ioaddr,
- struct dma_features *dma_cap)
+static int dwmac4_get_hw_feature(void __iomem *ioaddr,
+ struct dma_features *dma_cap)
{
u32 hw_cap = readl(ioaddr + GMAC_HW_FEATURE0);
@@ -437,6 +437,8 @@ static void dwmac4_get_hw_feature(void __iomem *ioaddr,
dma_cap->frpbs = (hw_cap & GMAC_HW_FEAT_FRPBS) >> 11;
dma_cap->frpsel = (hw_cap & GMAC_HW_FEAT_FRPSEL) >> 10;
dma_cap->dvlan = (hw_cap & GMAC_HW_FEAT_DVLAN) >> 5;
+
+ return 0;
}
/* Enable/disable TSO feature and set MSS */
@@ -371,8 +371,8 @@ static int dwxgmac2_dma_interrupt(void __iomem *ioaddr,
return ret;
}
-static void dwxgmac2_get_hw_feature(void __iomem *ioaddr,
- struct dma_features *dma_cap)
+static int dwxgmac2_get_hw_feature(void __iomem *ioaddr,
+ struct dma_features *dma_cap)
{
u32 hw_cap;
@@ -445,6 +445,8 @@ static void dwxgmac2_get_hw_feature(void __iomem *ioaddr,
dma_cap->frpes = (hw_cap & XGMAC_HWFEAT_FRPES) >> 11;
dma_cap->frpbs = (hw_cap & XGMAC_HWFEAT_FRPPB) >> 9;
dma_cap->frpsel = (hw_cap & XGMAC_HWFEAT_FRPSEL) >> 3;
+
+ return 0;
}
static void dwxgmac2_rx_watchdog(void __iomem *ioaddr, u32 riwt, u32 queue)
@@ -203,8 +203,8 @@ struct stmmac_dma_ops {
int (*dma_interrupt) (void __iomem *ioaddr,
struct stmmac_extra_stats *x, u32 chan, u32 dir);
/* If supported then get the optional core features */
- void (*get_hw_feature)(void __iomem *ioaddr,
- struct dma_features *dma_cap);
+ int (*get_hw_feature)(void __iomem *ioaddr,
+ struct dma_features *dma_cap);
/* Program the HW RX Watchdog */
void (*rx_watchdog)(void __iomem *ioaddr, u32 riwt, u32 queue);
void (*set_tx_ring_len)(void __iomem *ioaddr, u32 len, u32 chan);
@@ -255,7 +255,7 @@ struct stmmac_dma_ops {
#define stmmac_dma_interrupt_status(__priv, __args...) \
stmmac_do_callback(__priv, dma, dma_interrupt, __args)
#define stmmac_get_hw_feature(__priv, __args...) \
- stmmac_do_void_callback(__priv, dma, get_hw_feature, __args)
+ stmmac_do_callback(__priv, dma, get_hw_feature, __args)
#define stmmac_rx_watchdog(__priv, __args...) \
stmmac_do_void_callback(__priv, dma, rx_watchdog, __args)
#define stmmac_set_tx_ring_len(__priv, __args...) \
Some old IPs do not provide the hardware feature register. On these IPs, this register is read 0x00000000. In old driver version, this feature was handled but a regression came with the commit f10a6a3541b4 ("stmmac: rework get_hw_feature function"). Indeed, this commit removes the return value in dma->get_hw_feature(). This return value was used to indicate the validity of retrieved information and used later on in stmmac_hw_init() to override priv->plat data if this hardware feature were valid. This patch restores the return code in ->get_hw_feature() in order to indicate the hardware feature validity and override priv->plat data only if this hardware feature is valid. Fixes: f10a6a3541b4 ("stmmac: rework get_hw_feature function") Signed-off-by: Herve Codina <herve.codina@bootlin.com> --- drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c | 13 +++++++++++-- drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c | 6 ++++-- drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c | 6 ++++-- drivers/net/ethernet/stmicro/stmmac/hwif.h | 6 +++--- 4 files changed, 22 insertions(+), 9 deletions(-)