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| author | Pawel Dembicki <paweldembicki@gmail.com> | 2024-08-09 21:38:04 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2024-08-12 11:46:55 +0100 |
| commit | fa63c6434b6f6aaf9d8d599dc899bc0a074cc0ad (patch) | |
| tree | d64f43e49356e766a54b2cfc17abceeda59d4763 | |
| parent | 5b9eebc2c7a5f0cc7950d918c1e8a4ad4bed5010 (diff) | |
| download | lwn-fa63c6434b6f6aaf9d8d599dc899bc0a074cc0ad.tar.gz lwn-fa63c6434b6f6aaf9d8d599dc899bc0a074cc0ad.zip | |
net: dsa: vsc73xx: check busy flag in MDIO operations
The VSC73xx has a busy flag used during MDIO operations. It is raised
when MDIO read/write operations are in progress. Without it, PHYs are
misconfigured and bus operations do not work as expected.
Fixes: 05bd97fc559d ("net: dsa: Add Vitesse VSC73xx DSA router driver")
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Signed-off-by: Pawel Dembicki <paweldembicki@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | drivers/net/dsa/vitesse-vsc73xx-core.c | 37 |
1 files changed, 36 insertions, 1 deletions
diff --git a/drivers/net/dsa/vitesse-vsc73xx-core.c b/drivers/net/dsa/vitesse-vsc73xx-core.c index 4b300c293dec..a789b2da9b7d 100644 --- a/drivers/net/dsa/vitesse-vsc73xx-core.c +++ b/drivers/net/dsa/vitesse-vsc73xx-core.c @@ -40,6 +40,10 @@ #define VSC73XX_BLOCK_ARBITER 0x5 /* Only subblock 0 */ #define VSC73XX_BLOCK_SYSTEM 0x7 /* Only subblock 0 */ +/* MII Block subblock */ +#define VSC73XX_BLOCK_MII_INTERNAL 0x0 /* Internal MDIO subblock */ +#define VSC73XX_BLOCK_MII_EXTERNAL 0x1 /* External MDIO subblock */ + #define CPU_PORT 6 /* CPU port */ /* MAC Block registers */ @@ -225,6 +229,8 @@ #define VSC73XX_MII_CMD 0x1 #define VSC73XX_MII_DATA 0x2 +#define VSC73XX_MII_STAT_BUSY BIT(3) + /* Arbiter block 5 registers */ #define VSC73XX_ARBEMPTY 0x0c #define VSC73XX_ARBDISC 0x0e @@ -299,6 +305,7 @@ #define IS_739X(a) (IS_7395(a) || IS_7398(a)) #define VSC73XX_POLL_SLEEP_US 1000 +#define VSC73XX_MDIO_POLL_SLEEP_US 5 #define VSC73XX_POLL_TIMEOUT_US 10000 struct vsc73xx_counter { @@ -527,6 +534,22 @@ static int vsc73xx_detect(struct vsc73xx *vsc) return 0; } +static int vsc73xx_mdio_busy_check(struct vsc73xx *vsc) +{ + int ret, err; + u32 val; + + ret = read_poll_timeout(vsc73xx_read, err, + err < 0 || !(val & VSC73XX_MII_STAT_BUSY), + VSC73XX_MDIO_POLL_SLEEP_US, + VSC73XX_POLL_TIMEOUT_US, false, vsc, + VSC73XX_BLOCK_MII, VSC73XX_BLOCK_MII_INTERNAL, + VSC73XX_MII_STAT, &val); + if (ret) + return ret; + return err; +} + static int vsc73xx_phy_read(struct dsa_switch *ds, int phy, int regnum) { struct vsc73xx *vsc = ds->priv; @@ -534,12 +557,20 @@ static int vsc73xx_phy_read(struct dsa_switch *ds, int phy, int regnum) u32 val; int ret; + ret = vsc73xx_mdio_busy_check(vsc); + if (ret) + return ret; + /* Setting bit 26 means "read" */ cmd = BIT(26) | (phy << 21) | (regnum << 16); ret = vsc73xx_write(vsc, VSC73XX_BLOCK_MII, 0, 1, cmd); if (ret) return ret; - msleep(2); + + ret = vsc73xx_mdio_busy_check(vsc); + if (ret) + return ret; + ret = vsc73xx_read(vsc, VSC73XX_BLOCK_MII, 0, 2, &val); if (ret) return ret; @@ -563,6 +594,10 @@ static int vsc73xx_phy_write(struct dsa_switch *ds, int phy, int regnum, u32 cmd; int ret; + ret = vsc73xx_mdio_busy_check(vsc); + if (ret) + return ret; + /* It was found through tedious experiments that this router * chip really hates to have it's PHYs reset. They * never recover if that happens: autonegotiation stops |