]> git.baikalelectronics.ru Git - kernel.git/commitdiff
net: stmmac: fix get_hw_feature() on old hardware
authorHerve Codina <herve.codina@bootlin.com>
Fri, 8 Oct 2021 10:34:37 +0000 (12:34 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 20 Oct 2021 09:40:16 +0000 (11:40 +0200)
commit 075da584bae2da6a37428d59a477b6bdad430ac3 upstream.

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 55cd3d126443 ("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: 55cd3d126443 ("stmmac: rework get_hw_feature function")
Signed-off-by: Herve Codina <herve.codina@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c
drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c
drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
drivers/net/ethernet/stmicro/stmmac/hwif.h

index 2bac49b49f739233e5e9f94d2d8bc37d46162c76..fbf2deafe8ba31c33cfc08acbc1396c646bab6cc 100644 (file)
@@ -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,
index 0d993f4b701c248a0f61caa4304c3fdfa5d6ae2e..ae473d85b7fb8529510c3e8ed9727cd75ae74e06 100644 (file)
@@ -336,8 +336,8 @@ 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);
 
@@ -400,6 +400,8 @@ 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 */
index 4af7271cea5613f359898993e3897b407da63cd9..07ef0ac725b3e9cbc7fef2c76b78d81f312c0779 100644 (file)
@@ -356,8 +356,8 @@ 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;
 
@@ -425,6 +425,8 @@ 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 nchan)
index 9010d881b12e58ac13e531cc7dfdaeeeca256f8c..59a1d8c00372112015a4ca9b3a0afddf6ca647ef 100644 (file)
@@ -196,8 +196,8 @@ struct stmmac_dma_ops {
        int (*dma_interrupt) (void __iomem *ioaddr,
                              struct stmmac_extra_stats *x, u32 chan);
        /* 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 number_chan);
        void (*set_tx_ring_len)(void __iomem *ioaddr, u32 len, u32 chan);
@@ -247,7 +247,7 @@ 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...) \