[PATCH net-next v2 3/4] net: mvneta: Add naive RSS support

Gregory CLEMENT
2015-12-04T18:44:59Z

This patch adds the support for the RSS related ethtool
function. Currently it only uses one entry in the indirection table which
allows associating an mvneta interface to a given CPU.

Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Tested-by: Marcin Wojtas <mw@semihalf.com>
---
drivers/net/ethernet/marvell/mvneta.c | 127 +++++++++++++++++++++++++++++++++-
1 file changed, 126 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c
index 8974ab084839..e0dba6869605 100644
--- a/drivers/net/ethernet/marvell/mvneta.c
+++ b/drivers/net/ethernet/marvell/mvneta.c
@@ -259,6 +259,11 @@

#define MVNETA_TX_MTU_MAX 0x3ffff

+/* The RSS lookup table actually has 256 entries but we do not use
+ * them yet
+ */
+#define MVNETA_RSS_LU_TABLE_SIZE 1
+
/* TSO header size */
#define TSO_HEADER_SIZE 128

@@ -380,6 +385,8 @@ struct mvneta_port {
int use_inband_status:1;

u64 ethtool_stats[ARRAY_SIZE(mvneta_statistics)];
+
+ u32 indir[MVNETA_RSS_LU_TABLE_SIZE];
};

/* The mvneta_tx_desc and mvneta_rx_desc structures describe the
@@ -1027,7 +1034,7 @@ static void mvneta_defaults_set(struct mvneta_port *pp)
if ((rxq % max_cpu) == cpu)
rxq_map |= MVNETA_CPU_RXQ_ACCESS(rxq);

- if (cpu == rxq_def)
+ if (cpu == pp->rxq_def)
txq_map = MVNETA_CPU_TXQ_ACCESS_ALL_MASK;

mvreg_write(pp, MVNETA_CPU_MAP(cpu), rxq_map | txq_map);
@@ -2483,6 +2490,18 @@ static void mvneta_percpu_unmask_interrupt(void *arg)
MVNETA_MISCINTR_INTR_MASK);
}

+static void mvneta_percpu_mask_interrupt(void *arg)
+{
+ struct mvneta_port *pp = arg;
+
+ /* All the queue are masked, but actually only the ones
+ * maped to this CPU will be masked
+ */
+ mvreg_write(pp, MVNETA_INTR_NEW_MASK, 0);
+ mvreg_write(pp, MVNETA_INTR_OLD_MASK, 0);
+ mvreg_write(pp, MVNETA_INTR_MISC_MASK, 0);
+}
+
static void mvneta_start_dev(struct mvneta_port *pp)
{
unsigned int cpu;
@@ -3173,6 +3192,106 @@ static int mvneta_ethtool_get_sset_count(struct net_device *dev, int sset)
return -EOPNOTSUPP;
}

+static u32 mvneta_ethtool_get_rxfh_indir_size(struct net_device *dev)
+{
+ return MVNETA_RSS_LU_TABLE_SIZE;
+}
+
+static int mvneta_ethtool_get_rxnfc(struct net_device *dev,
+ struct ethtool_rxnfc *info,
+ u32 *rules __always_unused)
+{
+ switch (info->cmd) {
+ case ETHTOOL_GRXRINGS:
+ info->data = rxq_number;
+ return 0;
+ case ETHTOOL_GRXFH:
+ return -EOPNOTSUPP;
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static int mvneta_config_rss(struct mvneta_port *pp)
+{
+ int cpu;
+ u32 val;
+
+ netif_tx_stop_all_queues(pp->dev);
+
+ for_each_online_cpu(cpu)
+ smp_call_function_single(cpu, mvneta_percpu_mask_interrupt,
+ pp, true);
+
+ /* We have to synchronise on the napi of each CPU */
+ for_each_online_cpu(cpu) {
+ struct mvneta_pcpu_port *pcpu_port =
+ per_cpu_ptr(pp->ports, cpu);
+
+ napi_synchronize(&pcpu_port->napi);
+ napi_disable(&pcpu_port->napi);
+ }
+
+ pp->rxq_def = pp->indir[0];
+
+ /* Update unicast mapping */
+ mvneta_set_rx_mode(pp->dev);
+
+ /* Update val of portCfg register accordingly with all RxQueue types */
+ val = MVNETA_PORT_CONFIG_DEFL_VALUE(pp->rxq_def);
+ mvreg_write(pp, MVNETA_PORT_CONFIG, val);
+
+ /* Update the elected CPU matching the new rxq_def */
+ mvneta_percpu_elect(pp);
+
+ /* We have to synchronise on the napi of each CPU */
+ for_each_online_cpu(cpu) {
+ struct mvneta_pcpu_port *pcpu_port =
+ per_cpu_ptr(pp->ports, cpu);
+
+ napi_enable(&pcpu_port->napi);
+ }
+
+ netif_tx_start_all_queues(pp->dev);
+
+ return 0;
+}
+
+static int mvneta_ethtool_set_rxfh(struct net_device *dev, const u32 *indir,
+ const u8 *key, const u8 hfunc)
+{
+ struct mvneta_port *pp = netdev_priv(dev);
+ /* We require at least one supported parameter to be changed
+ * and no change in any of the unsupported parameters
+ */
+ if (key ||
+ (hfunc != ETH_RSS_HASH_NO_CHANGE && hfunc != ETH_RSS_HASH_TOP))
+ return -EOPNOTSUPP;
+
+ if (!indir)
+ return 0;
+
+ memcpy(pp->indir, indir, MVNETA_RSS_LU_TABLE_SIZE);
+
+ return mvneta_config_rss(pp);
+}
+
+static int mvneta_ethtool_get_rxfh(struct net_device *dev, u32 *indir, u8 *key,
+ u8 *hfunc)
+{
+ struct mvneta_port *pp = netdev_priv(dev);
+
+ if (hfunc)
+ *hfunc = ETH_RSS_HASH_TOP;
+
+ if (!indir)
+ return 0;
+
+ memcpy(indir, pp->indir, MVNETA_RSS_LU_TABLE_SIZE);
+
+ return 0;
+}
+
static const struct net_device_ops mvneta_netdev_ops = {
.ndo_open = mvneta_open,
.ndo_stop = mvneta_stop,
@@ -3197,6 +3316,10 @@ const struct ethtool_ops mvneta_eth_tool_ops = {
.get_strings = mvneta_ethtool_get_strings,
.get_ethtool_stats = mvneta_ethtool_get_stats,
.get_sset_count = mvneta_ethtool_get_sset_count,
+ .get_rxfh_indir_size = mvneta_ethtool_get_rxfh_indir_size,
+ .get_rxnfc = mvneta_ethtool_get_rxnfc,
+ .get_rxfh = mvneta_ethtool_get_rxfh,
+ .set_rxfh = mvneta_ethtool_set_rxfh,
};

/* Initialize hw */
@@ -3389,6 +3512,8 @@ static int mvneta_probe(struct platform_device *pdev)

pp->rxq_def = rxq_def;

+ pp->indir[0] = rxq_def;
+
pp->clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(pp->clk)) {
err = PTR_ERR(pp->clk);
--
2.5.0