| Message ID | 20210416001148.333969-1-ilya.lipnitskiy@gmail.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [net-next,v2] net: ethernet: mediatek: ppe: fix busy wait loop | expand |
On Thu, Apr 15, 2021 at 05:11:48PM -0700, Ilya Lipnitskiy wrote: > The intention is for the loop to timeout if the body does not succeed. > The current logic calls time_is_before_jiffies(timeout) which is false > until after the timeout, so the loop body never executes. > > Fix by using readl_poll_timeout as a more standard and less error-prone > solution. > > Fixes: ba37b7caf1ed ("net: ethernet: mtk_eth_soc: add support for initializing the PPE") > Signed-off-by: Ilya Lipnitskiy <ilya.lipnitskiy@gmail.com> > Cc: Felix Fietkau <nbd@nbd.name> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Andrew
diff --git a/drivers/net/ethernet/mediatek/mtk_ppe.c b/drivers/net/ethernet/mediatek/mtk_ppe.c index 71e1ccea6e72..f4b3fc0eeb50 100644 --- a/drivers/net/ethernet/mediatek/mtk_ppe.c +++ b/drivers/net/ethernet/mediatek/mtk_ppe.c @@ -5,6 +5,7 @@ #include <linux/jiffies.h> #include <linux/delay.h> #include <linux/io.h> +#include <linux/iopoll.h> #include <linux/etherdevice.h> #include <linux/platform_device.h> #include "mtk_ppe.h" @@ -44,18 +45,17 @@ static u32 ppe_clear(struct mtk_ppe *ppe, u32 reg, u32 val) static int mtk_ppe_wait_busy(struct mtk_ppe *ppe) { - unsigned long timeout = jiffies + HZ; - - while (time_is_before_jiffies(timeout)) { - if (!(ppe_r32(ppe, MTK_PPE_GLO_CFG) & MTK_PPE_GLO_CFG_BUSY)) - return 0; + int ret; + u32 val; - usleep_range(10, 20); - } + ret = readl_poll_timeout(ppe->base + MTK_PPE_GLO_CFG, val, + !(val & MTK_PPE_GLO_CFG_BUSY), + 20, MTK_PPE_WAIT_TIMEOUT_US); - dev_err(ppe->dev, "PPE table busy"); + if (ret) + dev_err(ppe->dev, "PPE table busy"); - return -ETIMEDOUT; + return ret; } static void mtk_ppe_cache_clear(struct mtk_ppe *ppe) diff --git a/drivers/net/ethernet/mediatek/mtk_ppe.h b/drivers/net/ethernet/mediatek/mtk_ppe.h index 51bd5e75bbbd..242fb8f2ae65 100644 --- a/drivers/net/ethernet/mediatek/mtk_ppe.h +++ b/drivers/net/ethernet/mediatek/mtk_ppe.h @@ -12,6 +12,7 @@ #define MTK_PPE_ENTRIES_SHIFT 3 #define MTK_PPE_ENTRIES (1024 << MTK_PPE_ENTRIES_SHIFT) #define MTK_PPE_HASH_MASK (MTK_PPE_ENTRIES - 1) +#define MTK_PPE_WAIT_TIMEOUT_US 1000000 #define MTK_FOE_IB1_UNBIND_TIMESTAMP GENMASK(7, 0) #define MTK_FOE_IB1_UNBIND_PACKETS GENMASK(23, 8)
The intention is for the loop to timeout if the body does not succeed. The current logic calls time_is_before_jiffies(timeout) which is false until after the timeout, so the loop body never executes. Fix by using readl_poll_timeout as a more standard and less error-prone solution. Fixes: ba37b7caf1ed ("net: ethernet: mtk_eth_soc: add support for initializing the PPE") Signed-off-by: Ilya Lipnitskiy <ilya.lipnitskiy@gmail.com> Cc: Felix Fietkau <nbd@nbd.name> --- drivers/net/ethernet/mediatek/mtk_ppe.c | 18 +++++++++--------- drivers/net/ethernet/mediatek/mtk_ppe.h | 1 + 2 files changed, 10 insertions(+), 9 deletions(-)