ag71xx: Fix rx ring buffer stall on small packets flood on qca956x and qca953x.

Backported from Code Aurora QSDK

Signed-off-by: Vittorio Gambaletta <openwrt@vittgam.net>

diff --git a/target/linux/ar71xx/files/arch/mips/ath79/dev-eth.c b/target/linux/ar71xx/files/arch/mips/ath79/dev-eth.c
index a8b19b68b2a46545fdd3ed6bdf14006f8a741185..427de6a50d0fcbc9dae11f8e6921194c0a5b09ed 100644 (file)
--- a/target/linux/ar71xx/files/arch/mips/ath79/dev-eth.c
+++ b/target/linux/ar71xx/files/arch/mips/ath79/dev-eth.c
@@ -996,6 +996,9 @@ void __init ath79_register_eth(unsigned int id)
                        pdata->reset_bit = AR934X_RESET_GE0_MAC |
                                           AR934X_RESET_GE0_MDIO;
                        pdata->set_speed = ar934x_set_speed_ge0;
+
+                       if (ath79_soc == ATH79_SOC_QCA9533)
+                               pdata->disable_inline_checksum_engine = 1;
                } else {
                        pdata->reset_bit = AR934X_RESET_GE1_MAC |
                                           AR934X_RESET_GE1_MDIO;
@@ -1097,6 +1100,8 @@ void __init ath79_register_eth(unsigned int id)
                                pdata->set_speed = qca956x_set_speed_sgmii;
                        else
                                pdata->set_speed = ar934x_set_speed_ge0;
+
+                       pdata->disable_inline_checksum_engine = 1;
                } else {
                        pdata->reset_bit = QCA955X_RESET_GE1_MAC |
                                           QCA955X_RESET_GE1_MDIO;

diff --git a/target/linux/ar71xx/files/arch/mips/include/asm/mach-ath79/ag71xx_platform.h b/target/linux/ar71xx/files/arch/mips/include/asm/mach-ath79/ag71xx_platform.h
index 078fa157f242ce4350185d97a61ef5d1f3f16fc5..5fdc59c7b78b84670daefa9fd831b154ded84ddc 100644 (file)
--- a/target/linux/ar71xx/files/arch/mips/include/asm/mach-ath79/ag71xx_platform.h
+++ b/target/linux/ar71xx/files/arch/mips/include/asm/mach-ath79/ag71xx_platform.h
@@ -37,7 +37,7 @@ struct ag71xx_platform_data {
        u8              is_ar724x:1;
        u8              has_ar8216:1;
        u8              use_flow_control:1;
-       u8              is_qca956x:1;
+       u8              disable_inline_checksum_engine:1;
 
        struct ag71xx_switch_platform_data *switch_data;
 

diff --git a/target/linux/ar71xx/files/drivers/net/ethernet/atheros/ag71xx/ag71xx_main.c b/target/linux/ar71xx/files/drivers/net/ethernet/atheros/ag71xx/ag71xx_main.c
index 566e9513d8b7c6ef101902ae7d281dcc1c233893..72dd654a691355c881b15d796fad0d640e05fc15 100644 (file)
--- a/target/linux/ar71xx/files/drivers/net/ethernet/atheros/ag71xx/ag71xx_main.c
+++ b/target/linux/ar71xx/files/drivers/net/ethernet/atheros/ag71xx/ag71xx_main.c
@@ -629,6 +629,22 @@ __ag71xx_link_adjust(struct ag71xx *ag, bool update)
        ag71xx_wr(ag, AG71XX_REG_MAC_CFG2, cfg2);
        ag71xx_wr(ag, AG71XX_REG_FIFO_CFG5, fifo5);
        ag71xx_wr(ag, AG71XX_REG_MAC_IFCTL, ifctl);
+
+       if (pdata->disable_inline_checksum_engine) {
+               /*
+                * The rx ring buffer can stall on small packets on QCA953x and
+                * QCA956x. Disabling the inline checksum engine fixes the stall.
+                * The wr, rr functions cannot be used since this hidden register
+                * is outside of the normal ag71xx register block.
+                */
+               void __iomem *dam = ioremap_nocache(0xb90001bc, 0x4);
+               if (dam) {
+                       __raw_writel(__raw_readl(dam) & ~BIT(27), dam);
+                       (void)__raw_readl(dam);
+                       iounmap(dam);
+               }
+       }
+
        ag71xx_hw_start(ag);
 
        netif_carrier_on(ag->dev);