From ed102be70f762afc39bda165ba57ea84dc9be39e Mon Sep 17 00:00:00 2001 From: Alexey Brodkin Date: Wed, 25 Sep 2013 19:27:48 +0400 Subject: [PATCH] net: designware: Fix alignment of buffer descriptors It's important that buffer descriptors are aligned in accordance to GMAC data bus width (32/64/128-bit). It's safe to align to 128-bit (16-bytes) for every bus width type. If buffer descriptor is improperly aligned GMAC discards lower bits of provided address and as a result reads from improper location that doesn't match expected fields. Commit ef76025a99247cdb8f927a2c9f15400678dfb599 "net: Multiple updates/enhancements to designware.c" introduced another structure member "link_printed" right before buffer descriptors while "padding" member was left untouched. This together with alignment of structure itself to 16-byte boundary forces buffer descriptoprs always to be 4-byte aligned that causes driver complete disfunction if GMAC bus width is 64 or 128-bit. Proposed change makes sure all buffer descriptors are 16-byte (128-bit) aligned. Signed-off-by: Alexey Brodkin Patch: 277902 --- drivers/net/designware.h | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/net/designware.h b/drivers/net/designware.h index e80002a0e4..5440c9215f 100644 --- a/drivers/net/designware.h +++ b/drivers/net/designware.h @@ -112,7 +112,7 @@ struct dmamacdescr { u32 dmamac_cntl; void *dmamac_addr; struct dmamacdescr *dmamac_next; -}; +} __aligned(16); /* * txrx_status definitions @@ -224,8 +224,7 @@ struct dw_eth_dev { u32 tx_currdescnum; u32 rx_currdescnum; u32 phy_configured; - int link_printed; - u32 padding; + u32 link_printed; struct dmamacdescr tx_mac_descrtable[CONFIG_TX_DESCR_NUM]; struct dmamacdescr rx_mac_descrtable[CONFIG_RX_DESCR_NUM]; @@ -237,7 +236,7 @@ struct dw_eth_dev { struct eth_dma_regs *dma_regs_p; struct eth_device *dev; -} __attribute__ ((aligned(8))); +}; /* Speed specific definitions */ #define SPEED_10M 1 -- 2.39.5