The GEther-like controllers have writeable RDFAR/TDFAR, on the others they are read-only or just absent (on R-Car). Currently we are calling sh_eth_is_{gether|rz_fast_ether}() in order to check if these registers can be written to, however it would be simpler to check the new 'xdfar_rw' bitfield in the 'struct sh_eth_cpu_data'... Signed-off-by: Sergei Shtylyov <sergei.shtylyov@xxxxxxxxxxxxxxxxxx> --- drivers/net/ethernet/renesas/sh_eth.c | 11 +++++++---- drivers/net/ethernet/renesas/sh_eth.h | 1 + 2 files changed, 8 insertions(+), 4 deletions(-) Index: net-next/drivers/net/ethernet/renesas/sh_eth.c =================================================================== --- net-next.orig/drivers/net/ethernet/renesas/sh_eth.c +++ net-next/drivers/net/ethernet/renesas/sh_eth.c @@ -611,6 +611,7 @@ static struct sh_eth_cpu_data r7s72100_d .rpadir_value = 2 << 16, .no_trimd = 1, .no_ade = 1, + .xdfar_rw = 1, .hw_checksum = 1, .tsu = 1, }; @@ -659,6 +660,7 @@ static struct sh_eth_cpu_data r8a7740_da .rpadir_value = 2 << 16, .no_trimd = 1, .no_ade = 1, + .xdfar_rw = 1, .hw_checksum = 1, .tsu = 1, .select_mii = 1, @@ -918,6 +920,7 @@ static struct sh_eth_cpu_data sh7757_dat .rpadir_value = 2 << 16, .no_trimd = 1, .no_ade = 1, + .xdfar_rw = 1, .tsu = 1, .dual_port = 1, }; @@ -955,6 +958,7 @@ static struct sh_eth_cpu_data sh7734_dat .hw_swap = 1, .no_trimd = 1, .no_ade = 1, + .xdfar_rw = 1, .tsu = 1, .hw_checksum = 1, .select_mii = 1, @@ -993,6 +997,7 @@ static struct sh_eth_cpu_data sh7763_dat .hw_swap = 1, .no_trimd = 1, .no_ade = 1, + .xdfar_rw = 1, .tsu = 1, .irq_flags = IRQF_SHARED, .magic = 1, @@ -1301,8 +1306,7 @@ static void sh_eth_ring_format(struct ne /* Rx descriptor address set */ if (i == 0) { sh_eth_write(ndev, mdp->rx_desc_dma, RDLAR); - if (sh_eth_is_gether(mdp) || - sh_eth_is_rz_fast_ether(mdp)) + if (mdp->cd->xdfar_rw) sh_eth_write(ndev, mdp->rx_desc_dma, RDFAR); } } @@ -1324,8 +1328,7 @@ static void sh_eth_ring_format(struct ne if (i == 0) { /* Tx descriptor address set */ sh_eth_write(ndev, mdp->tx_desc_dma, TDLAR); - if (sh_eth_is_gether(mdp) || - sh_eth_is_rz_fast_ether(mdp)) + if (mdp->cd->xdfar_rw) sh_eth_write(ndev, mdp->tx_desc_dma, TDFAR); } } Index: net-next/drivers/net/ethernet/renesas/sh_eth.h =================================================================== --- net-next.orig/drivers/net/ethernet/renesas/sh_eth.h +++ net-next/drivers/net/ethernet/renesas/sh_eth.h @@ -508,6 +508,7 @@ struct sh_eth_cpu_data { unsigned rpadir:1; /* E-DMAC have RPADIR */ unsigned no_trimd:1; /* E-DMAC DO NOT have TRIMD */ unsigned no_ade:1; /* E-DMAC DO NOT have ADE bit in EESR */ + unsigned xdfar_rw:1; /* E-DMAC has writeable RDFAR/TDFAR */ unsigned hw_checksum:1; /* E-DMAC has CSMR */ unsigned select_mii:1; /* EtherC have RMII_MII (MII select register) */ unsigned rmiimode:1; /* EtherC has RMIIMODE register */