net: stmmac: handle endianness in dwmac4_get_timestamp

[ Upstream commit 224babd62d6f19581757a6d8bae3bf9501fc10de ]

GMAC IP is little-endian and used on several kind of CPU (big or little
endian). Main callbacks functions of the stmmac drivers take care about
it. It was not the case for dwmac4_get_timestamp function.

Fixes: ba1ffd74df74 ("stmmac: fix PTP support for GMAC4")
Signed-off-by: Alexandre Torgue <alexandre.torgue@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c
index a601f8d43b75d8a97cc007ebaad4eed9ebd66ae3..f988c7573ba591de077d24024b9ac99fa699ae3f 100644 (file)
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c
@@ -237,15 +237,18 @@ static inline u64 dwmac4_get_timestamp(void *desc, u32 ats)
 static int dwmac4_rx_check_timestamp(void *desc)
 {
        struct dma_desc *p = (struct dma_desc *)desc;
+       unsigned int rdes0 = le32_to_cpu(p->des0);
+       unsigned int rdes1 = le32_to_cpu(p->des1);
+       unsigned int rdes3 = le32_to_cpu(p->des3);
        u32 own, ctxt;
        int ret = 1;
 
-       own = p->des3 & RDES3_OWN;
-       ctxt = ((p->des3 & RDES3_CONTEXT_DESCRIPTOR)
+       own = rdes3 & RDES3_OWN;
+       ctxt = ((rdes3 & RDES3_CONTEXT_DESCRIPTOR)
                >> RDES3_CONTEXT_DESCRIPTOR_SHIFT);
 
        if (likely(!own && ctxt)) {
-               if ((p->des0 == 0xffffffff) && (p->des1 == 0xffffffff))
+               if ((rdes0 == 0xffffffff) && (rdes1 == 0xffffffff))
                        /* Corrupted value */
                        ret = -EINVAL;
                else