From: Maxime Chevallier Date: Fri, 26 Nov 2021 11:20:56 +0000 (+0100) Subject: net: mvneta: Add TC traffic shaping offload X-Git-Tag: microblaze-v5.18~173^2~326^2 X-Git-Url: http://git.monstr.eu/?a=commitdiff_plain;h=2551dc9e398c37a15e52122d385c29a8b06be45f;p=linux-2.6-microblaze.git net: mvneta: Add TC traffic shaping offload The mvneta controller is able to do some tocken-bucket per-queue traffic shaping. This commit adds support for setting these using the TC mqprio interface. The token-bucket parameters are customisable, but the current implementation configures them to have a 10kbps resolution for the rate limitation, since it allows to cover the whole range of max_rate values from 10kbps to 5Gbps with 10kbps increments. Signed-off-by: Maxime Chevallier Signed-off-by: David S. Miller --- diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c index aba452e8abfe..2368ae3f0e10 100644 --- a/drivers/net/ethernet/marvell/mvneta.c +++ b/drivers/net/ethernet/marvell/mvneta.c @@ -248,12 +248,39 @@ #define MVNETA_TXQ_SENT_DESC_MASK 0x3fff0000 #define MVNETA_PORT_TX_RESET 0x3cf0 #define MVNETA_PORT_TX_DMA_RESET BIT(0) +#define MVNETA_TXQ_CMD1_REG 0x3e00 +#define MVNETA_TXQ_CMD1_BW_LIM_SEL_V1 BIT(3) +#define MVNETA_TXQ_CMD1_BW_LIM_EN BIT(0) +#define MVNETA_REFILL_NUM_CLK_REG 0x3e08 +#define MVNETA_REFILL_MAX_NUM_CLK 0x0000ffff #define MVNETA_TX_MTU 0x3e0c #define MVNETA_TX_TOKEN_SIZE 0x3e14 #define MVNETA_TX_TOKEN_SIZE_MAX 0xffffffff +#define MVNETA_TXQ_BUCKET_REFILL_REG(q) (0x3e20 + ((q) << 2)) +#define MVNETA_TXQ_BUCKET_REFILL_PERIOD_MASK 0x3ff00000 +#define MVNETA_TXQ_BUCKET_REFILL_PERIOD_SHIFT 20 +#define MVNETA_TXQ_BUCKET_REFILL_VALUE_MAX 0x0007ffff #define MVNETA_TXQ_TOKEN_SIZE_REG(q) (0x3e40 + ((q) << 2)) #define MVNETA_TXQ_TOKEN_SIZE_MAX 0x7fffffff +/* The values of the bucket refill base period and refill period are taken from + * the reference manual, and adds up to a base resolution of 10Kbps. This allows + * to cover all rate-limit values from 10Kbps up to 5Gbps + */ + +/* Base period for the rate limit algorithm */ +#define MVNETA_TXQ_BUCKET_REFILL_BASE_PERIOD_NS 100 + +/* Number of Base Period to wait between each bucket refill */ +#define MVNETA_TXQ_BUCKET_REFILL_PERIOD 1000 + +/* The base resolution for rate limiting, in bps. Any max_rate value should be + * a multiple of that value. + */ +#define MVNETA_TXQ_RATE_LIMIT_RESOLUTION (NSEC_PER_SEC / \ + (MVNETA_TXQ_BUCKET_REFILL_BASE_PERIOD_NS * \ + MVNETA_TXQ_BUCKET_REFILL_PERIOD)) + #define MVNETA_LPI_CTRL_0 0x2cc0 #define MVNETA_LPI_CTRL_1 0x2cc4 #define MVNETA_LPI_REQUEST_ENABLE BIT(0) @@ -4906,11 +4933,74 @@ static void mvneta_map_vlan_prio_to_rxq(struct mvneta_port *pp, u8 pri, u8 rxq) mvreg_write(pp, MVNETA_VLAN_PRIO_TO_RXQ, val); } +static int mvneta_enable_per_queue_rate_limit(struct mvneta_port *pp) +{ + unsigned long core_clk_rate; + u32 refill_cycles; + u32 val; + + core_clk_rate = clk_get_rate(pp->clk); + if (!core_clk_rate) + return -EINVAL; + + refill_cycles = MVNETA_TXQ_BUCKET_REFILL_BASE_PERIOD_NS / + (NSEC_PER_SEC / core_clk_rate); + + if (refill_cycles > MVNETA_REFILL_MAX_NUM_CLK) + return -EINVAL; + + /* Enable bw limit algorithm version 3 */ + val = mvreg_read(pp, MVNETA_TXQ_CMD1_REG); + val &= ~(MVNETA_TXQ_CMD1_BW_LIM_SEL_V1 | MVNETA_TXQ_CMD1_BW_LIM_EN); + mvreg_write(pp, MVNETA_TXQ_CMD1_REG, val); + + /* Set the base refill rate */ + mvreg_write(pp, MVNETA_REFILL_NUM_CLK_REG, refill_cycles); + + return 0; +} + +static void mvneta_disable_per_queue_rate_limit(struct mvneta_port *pp) +{ + u32 val = mvreg_read(pp, MVNETA_TXQ_CMD1_REG); + + val |= (MVNETA_TXQ_CMD1_BW_LIM_SEL_V1 | MVNETA_TXQ_CMD1_BW_LIM_EN); + mvreg_write(pp, MVNETA_TXQ_CMD1_REG, val); +} + +static int mvneta_setup_queue_rates(struct mvneta_port *pp, int queue, + u64 min_rate, u64 max_rate) +{ + u32 refill_val, rem; + u32 val = 0; + + /* Convert to from Bps to bps */ + max_rate *= 8; + + if (min_rate) + return -EINVAL; + + refill_val = div_u64_rem(max_rate, MVNETA_TXQ_RATE_LIMIT_RESOLUTION, + &rem); + + if (rem || !refill_val || + refill_val > MVNETA_TXQ_BUCKET_REFILL_VALUE_MAX) + return -EINVAL; + + val = refill_val; + val |= (MVNETA_TXQ_BUCKET_REFILL_PERIOD << + MVNETA_TXQ_BUCKET_REFILL_PERIOD_SHIFT); + + mvreg_write(pp, MVNETA_TXQ_BUCKET_REFILL_REG(queue), val); + + return 0; +} + static int mvneta_setup_mqprio(struct net_device *dev, struct tc_mqprio_qopt_offload *mqprio) { struct mvneta_port *pp = netdev_priv(dev); - int rxq, tc; + int rxq, txq, tc, ret; u8 num_tc; if (mqprio->qopt.hw != TC_MQPRIO_HW_OFFLOAD_TCS) @@ -4924,6 +5014,7 @@ static int mvneta_setup_mqprio(struct net_device *dev, mvneta_clear_rx_prio_map(pp); if (!num_tc) { + mvneta_disable_per_queue_rate_limit(pp); netdev_reset_tc(dev); return 0; } @@ -4944,6 +5035,33 @@ static int mvneta_setup_mqprio(struct net_device *dev, } } + if (mqprio->shaper != TC_MQPRIO_SHAPER_BW_RATE) { + mvneta_disable_per_queue_rate_limit(pp); + return 0; + } + + if (mqprio->qopt.num_tc > txq_number) + return -EINVAL; + + ret = mvneta_enable_per_queue_rate_limit(pp); + if (ret) + return ret; + + for (tc = 0; tc < mqprio->qopt.num_tc; tc++) { + for (txq = mqprio->qopt.offset[tc]; + txq < mqprio->qopt.count[tc] + mqprio->qopt.offset[tc]; + txq++) { + if (txq >= txq_number) + return -EINVAL; + + ret = mvneta_setup_queue_rates(pp, txq, + mqprio->min_rate[tc], + mqprio->max_rate[tc]); + if (ret) + return ret; + } + } + return 0; }