[PATCH 1/2] net: macb: Add on the fly CPU endianness detection
flat view
STALE4253d
REVIEWED: 2 (0M)
From: Arun Chandran <hidden>
Date: 2015-03-01 06:09:00
Also in:
lkml
Subsystem:
atmel macb ethernet driver, networking drivers, the rest · Maintainers:
Théo Lebrun, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
2 review trailers.
Program management descriptor's access mode according to the dynamically detected CPU endianness. Signed-off-by: Arun Chandran <redacted> Acked-by: Nicolas Ferre <redacted> Tested-by: Michal Simek <redacted> --- * Adding CPU endianness detection according to Michal Simek * Added Acked-by: Nicolas Ferre * Added Tested-by: Michal Simek --- --- drivers/net/ethernet/cadence/macb.c | 22 ++++++++++++++++++---- 1 file changed, 18 insertions(+), 4 deletions(-)
diff --git a/drivers/net/ethernet/cadence/macb.c b/drivers/net/ethernet/cadence/macb.c
index 05fb36d..1fe8b94 100644
--- a/drivers/net/ethernet/cadence/macb.c
+++ b/drivers/net/ethernet/cadence/macb.c@@ -1578,6 +1578,7 @@ static u32 macb_dbw(struct macb *bp) static void macb_configure_dma(struct macb *bp) { u32 dmacfg; + u32 tmp, ncr; if (macb_is_gem(bp)) { dmacfg = gem_readl(bp, DMACFG) & ~GEM_BF(RXBS, -1L);
@@ -1586,10 +1587,23 @@ static void macb_configure_dma(struct macb *bp) dmacfg = GEM_BFINS(FBLDO, bp->dma_burst_length, dmacfg); dmacfg |= GEM_BIT(TXPBMS) | GEM_BF(RXBMS, -1L); dmacfg &= ~GEM_BIT(ENDIA_PKT); - /* Tell the chip to byteswap descriptors on big-endian hosts */ -#ifdef __BIG_ENDIAN - dmacfg |= GEM_BIT(ENDIA_DESC); -#endif + + /* Find the CPU endianness by using the loopback bit of net_ctrl + * register. save it first. When the CPU is in big endian we + * need to program swaped mode for management descriptor access. + */ + ncr = macb_readl(bp, NCR); + __raw_writel(MACB_BIT(LLB), bp->regs + MACB_NCR); + tmp = __raw_readl(bp->regs + MACB_NCR); + + if (tmp == MACB_BIT(LLB)) + dmacfg &= ~GEM_BIT(ENDIA_DESC); + else + dmacfg |= GEM_BIT(ENDIA_DESC); /* CPU in big endian */ + + /* Restore net_ctrl */ + macb_writel(bp, NCR, ncr); + if (bp->dev->features & NETIF_F_HW_CSUM) dmacfg |= GEM_BIT(TXCOEN); else
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1.9.1