From 404cd086f29e867fc99f1174e8f3246a4ea14b7b Mon Sep 17 00:00:00 2001 From: Harini Katakam Date: Fri, 6 Jul 2018 12:18:58 +0530 Subject: net: macb: Allocate valid memory for TX and RX BD prefetch GEM version in ZynqMP and most versions greater than r1p07 supports TX and RX BD prefetch. The number of BDs that can be prefetched is a HW configurable parameter. For ZynqMP, this parameter is 4. When GEM DMA is accessing the last BD in the ring, even before the BD is processed and the WRAP bit is noticed, it will have prefetched BDs outside the BD ring. These will not be processed but it is necessary to have accessible memory after the last BD. Especially in cases where SMMU is used, memory locations immediately after the last BD may not have translation tables triggering HRESP errors. Hence always allocate extra BDs to accommodate for prefetch. The value of tx/rx bd prefetch for any given SoC version is: 2 ^ (corresponding field in design config 10 register). (value of this field >= 1) Added a capability flag so that older IP versions that do not have DCFG10 or this prefetch capability are not affected. Signed-off-by: Harini Katakam Reviewed-by: Claudiu Beznea Signed-off-by: David S. Miller --- drivers/net/ethernet/cadence/macb.h | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'drivers/net/ethernet/cadence/macb.h') diff --git a/drivers/net/ethernet/cadence/macb.h b/drivers/net/ethernet/cadence/macb.h index 86659823b259..3d45f4c92cf6 100644 --- a/drivers/net/ethernet/cadence/macb.h +++ b/drivers/net/ethernet/cadence/macb.h @@ -166,6 +166,7 @@ #define GEM_DCFG6 0x0294 /* Design Config 6 */ #define GEM_DCFG7 0x0298 /* Design Config 7 */ #define GEM_DCFG8 0x029C /* Design Config 8 */ +#define GEM_DCFG10 0x02A4 /* Design Config 10 */ #define GEM_TXBDCTRL 0x04cc /* TX Buffer Descriptor control register */ #define GEM_RXBDCTRL 0x04d0 /* RX Buffer Descriptor control register */ @@ -490,6 +491,12 @@ #define GEM_SCR2CMP_OFFSET 0 #define GEM_SCR2CMP_SIZE 8 +/* Bitfields in DCFG10 */ +#define GEM_TXBD_RDBUFF_OFFSET 12 +#define GEM_TXBD_RDBUFF_SIZE 4 +#define GEM_RXBD_RDBUFF_OFFSET 8 +#define GEM_RXBD_RDBUFF_SIZE 4 + /* Bitfields in TISUBN */ #define GEM_SUBNSINCR_OFFSET 0 #define GEM_SUBNSINCR_SIZE 16 @@ -635,6 +642,7 @@ #define MACB_CAPS_USRIO_DISABLED 0x00000010 #define MACB_CAPS_JUMBO 0x00000020 #define MACB_CAPS_GEM_HAS_PTP 0x00000040 +#define MACB_CAPS_BD_RD_PREFETCH 0x00000080 #define MACB_CAPS_FIFO_MODE 0x10000000 #define MACB_CAPS_GIGABIT_MODE_AVAILABLE 0x20000000 #define MACB_CAPS_SG_DISABLED 0x40000000 @@ -1203,6 +1211,9 @@ struct macb { unsigned int max_tuples; struct tasklet_struct hresp_err_tasklet; + + int rx_bd_rd_prefetch; + int tx_bd_rd_prefetch; }; #ifdef CONFIG_MACB_USE_HWSTAMP -- cgit v1.2.3