The assumption that Documentation was right about how this value work was wrong. It was discovered that the length value of the mgmt header is in step of word size.
As an example to process 4 byte of data the correct length to set is 2. To process 8 byte 4, 12 byte 6, 16 byte 8...
Odd values will always return the next size on the ack packet. (length of 3 (6 byte) will always return 8 bytes of data)
This means that a value of 15 (0xf) actually means reading/writing 32 bytes of data instead of 16 bytes. This behaviour is totally absent and not documented in the switch Documentation.
In fact from Documentation the max value that mgmt eth can process is 16 byte of data while in reality it can process 32 bytes at once.
To handle this we always round up the length after deviding it for word size. We check if the result is odd and we round another time to align to what the switch will provide in the ack packet. The workaround for the length limit of 15 is still needed as the length reg max value is 0xf(15)
Reported-by: Ronald Wahl ronald.wahl@raritan.com Tested-by: Ronald Wahl ronald.wahl@raritan.com Fixes: 90386223f44e ("net: dsa: qca8k: add support for larger read/write size with mgmt Ethernet") Signed-off-by: Christian Marangi ansuelsmth@gmail.com Cc: stable@vger.kernel.org # v5.18+ --- drivers/net/dsa/qca/qca8k-8xxx.c | 45 +++++++++++++++++++++++++------- 1 file changed, 35 insertions(+), 10 deletions(-)
diff --git a/drivers/net/dsa/qca/qca8k-8xxx.c b/drivers/net/dsa/qca/qca8k-8xxx.c index c5c3b4e92f28..46151320b2a8 100644 --- a/drivers/net/dsa/qca/qca8k-8xxx.c +++ b/drivers/net/dsa/qca/qca8k-8xxx.c @@ -146,7 +146,16 @@ static void qca8k_rw_reg_ack_handler(struct dsa_switch *ds, struct sk_buff *skb)
command = get_unaligned_le32(&mgmt_ethhdr->command); cmd = FIELD_GET(QCA_HDR_MGMT_CMD, command); + len = FIELD_GET(QCA_HDR_MGMT_LENGTH, command); + /* Special case for len of 15 as this is the max value for len and needs to + * be increased before converting it from word to dword. + */ + if (len == 15) + len++; + + /* We can ignore odd value, we always round up them in the alloc function. */ + len *= sizeof(u16);
/* Make sure the seq match the requested packet */ if (get_unaligned_le32(&mgmt_ethhdr->seq) == mgmt_eth_data->seq) @@ -193,17 +202,33 @@ static struct sk_buff *qca8k_alloc_mdio_header(enum mdio_cmd cmd, u32 reg, u32 * if (!skb) return NULL;
- /* Max value for len reg is 15 (0xf) but the switch actually return 16 byte - * Actually for some reason the steps are: - * 0: nothing - * 1-4: first 4 byte - * 5-6: first 12 byte - * 7-15: all 16 byte + /* Hdr mgmt length value is in step of word size. + * As an example to process 4 byte of data the correct length to set is 2. + * To process 8 byte 4, 12 byte 6, 16 byte 8... + * + * Odd values will always return the next size on the ack packet. + * (length of 3 (6 byte) will always return 8 bytes of data) + * + * This means that a value of 15 (0xf) actually means reading/writing 32 bytes + * of data. + * + * To correctly calculate the length we devide the requested len by word and + * round up. + * On the ack function we can skip the odd check as we already handle the + * case here. + */ + real_len = DIV_ROUND_UP(len, sizeof(u16)); + + /* We check if the result len is odd and we round up another time to + * the next size. (length of 3 will be increased to 4 as switch will always + * return 8 bytes) */ - if (len == 16) - real_len = 15; - else - real_len = len; + if (real_len % sizeof(u16) != 0) + real_len++; + + /* Max reg value is 0xf(15) but switch will always return the next size (32 byte) */ + if (real_len == 16) + real_len--;
skb_reset_mac_header(skb); skb_set_network_header(skb, skb->len);
It was discovered that MGMT_DATA2 can contain up to 28 bytes of data instead of the 12 bytes written in the Documentation by accounting the limit of 16 bytes declared in Documentation subtracting the first 4 byte in the packet header.
Update the define with the real world value.
Tested-by: Ronald Wahl ronald.wahl@raritan.com Fixes: c2ee8181fddb ("net: dsa: tag_qca: add define for handling mgmt Ethernet packet") Signed-off-by: Christian Marangi ansuelsmth@gmail.com Cc: stable@vger.kernel.org # v5.18+ --- include/linux/dsa/tag_qca.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/include/linux/dsa/tag_qca.h b/include/linux/dsa/tag_qca.h index b1b5720d89a5..ee657452f122 100644 --- a/include/linux/dsa/tag_qca.h +++ b/include/linux/dsa/tag_qca.h @@ -45,8 +45,8 @@ struct sk_buff; QCA_HDR_MGMT_COMMAND_LEN + \ QCA_HDR_MGMT_DATA1_LEN)
-#define QCA_HDR_MGMT_DATA2_LEN 12 /* Other 12 byte for the mdio data */ -#define QCA_HDR_MGMT_PADDING_LEN 34 /* Padding to reach the min Ethernet packet */ +#define QCA_HDR_MGMT_DATA2_LEN 28 /* Other 28 byte for the mdio data */ +#define QCA_HDR_MGMT_PADDING_LEN 18 /* Padding to reach the min Ethernet packet */
#define QCA_HDR_MGMT_PKT_LEN (QCA_HDR_MGMT_HEADER_LEN + \ QCA_HDR_LEN + \
This reverts commit 2481d206fae7884cd07014fd1318e63af35e99eb.
The Documentation is very confusing about the topic. The cache logic for hi and lo is wrong and actually miss some regs to be actually written.
What the Docuemntation actually intended was that it's possible to skip writing hi OR lo if half of the reg is not needed to be written or read.
Revert the change in favor of a better and correct implementation.
Reported-by: Ronald Wahl ronald.wahl@raritan.com Signed-off-by: Christian Marangi ansuelsmth@gmail.com Cc: stable@vger.kernel.org # v5.18+ --- drivers/net/dsa/qca/qca8k-8xxx.c | 61 +++++++------------------------- drivers/net/dsa/qca/qca8k.h | 5 --- 2 files changed, 12 insertions(+), 54 deletions(-)
diff --git a/drivers/net/dsa/qca/qca8k-8xxx.c b/drivers/net/dsa/qca/qca8k-8xxx.c index 46151320b2a8..fbcd5c2b13ae 100644 --- a/drivers/net/dsa/qca/qca8k-8xxx.c +++ b/drivers/net/dsa/qca/qca8k-8xxx.c @@ -36,44 +36,6 @@ qca8k_split_addr(u32 regaddr, u16 *r1, u16 *r2, u16 *page) *page = regaddr & 0x3ff; }
-static int -qca8k_set_lo(struct qca8k_priv *priv, int phy_id, u32 regnum, u16 lo) -{ - u16 *cached_lo = &priv->mdio_cache.lo; - struct mii_bus *bus = priv->bus; - int ret; - - if (lo == *cached_lo) - return 0; - - ret = bus->write(bus, phy_id, regnum, lo); - if (ret < 0) - dev_err_ratelimited(&bus->dev, - "failed to write qca8k 32bit lo register\n"); - - *cached_lo = lo; - return 0; -} - -static int -qca8k_set_hi(struct qca8k_priv *priv, int phy_id, u32 regnum, u16 hi) -{ - u16 *cached_hi = &priv->mdio_cache.hi; - struct mii_bus *bus = priv->bus; - int ret; - - if (hi == *cached_hi) - return 0; - - ret = bus->write(bus, phy_id, regnum, hi); - if (ret < 0) - dev_err_ratelimited(&bus->dev, - "failed to write qca8k 32bit hi register\n"); - - *cached_hi = hi; - return 0; -} - static int qca8k_mii_read32(struct mii_bus *bus, int phy_id, u32 regnum, u32 *val) { @@ -97,7 +59,7 @@ qca8k_mii_read32(struct mii_bus *bus, int phy_id, u32 regnum, u32 *val) }
static void -qca8k_mii_write32(struct qca8k_priv *priv, int phy_id, u32 regnum, u32 val) +qca8k_mii_write32(struct mii_bus *bus, int phy_id, u32 regnum, u32 val) { u16 lo, hi; int ret; @@ -105,9 +67,12 @@ qca8k_mii_write32(struct qca8k_priv *priv, int phy_id, u32 regnum, u32 val) lo = val & 0xffff; hi = (u16)(val >> 16);
- ret = qca8k_set_lo(priv, phy_id, regnum, lo); + ret = bus->write(bus, phy_id, regnum, lo); if (ret >= 0) - ret = qca8k_set_hi(priv, phy_id, regnum + 1, hi); + ret = bus->write(bus, phy_id, regnum + 1, hi); + if (ret < 0) + dev_err_ratelimited(&bus->dev, + "failed to write qca8k 32bit register\n"); }
static int @@ -442,7 +407,7 @@ qca8k_regmap_write(void *ctx, uint32_t reg, uint32_t val) if (ret < 0) goto exit;
- qca8k_mii_write32(priv, 0x10 | r2, r1, val); + qca8k_mii_write32(bus, 0x10 | r2, r1, val);
exit: mutex_unlock(&bus->mdio_lock); @@ -475,7 +440,7 @@ qca8k_regmap_update_bits(void *ctx, uint32_t reg, uint32_t mask, uint32_t write_
val &= ~mask; val |= write_val; - qca8k_mii_write32(priv, 0x10 | r2, r1, val); + qca8k_mii_write32(bus, 0x10 | r2, r1, val);
exit: mutex_unlock(&bus->mdio_lock); @@ -750,14 +715,14 @@ qca8k_mdio_write(struct qca8k_priv *priv, int phy, int regnum, u16 data) if (ret) goto exit;
- qca8k_mii_write32(priv, 0x10 | r2, r1, val); + qca8k_mii_write32(bus, 0x10 | r2, r1, val);
ret = qca8k_mdio_busy_wait(bus, QCA8K_MDIO_MASTER_CTRL, QCA8K_MDIO_MASTER_BUSY);
exit: /* even if the busy_wait timeouts try to clear the MASTER_EN */ - qca8k_mii_write32(priv, 0x10 | r2, r1, 0); + qca8k_mii_write32(bus, 0x10 | r2, r1, 0);
mutex_unlock(&bus->mdio_lock);
@@ -787,7 +752,7 @@ qca8k_mdio_read(struct qca8k_priv *priv, int phy, int regnum) if (ret) goto exit;
- qca8k_mii_write32(priv, 0x10 | r2, r1, val); + qca8k_mii_write32(bus, 0x10 | r2, r1, val);
ret = qca8k_mdio_busy_wait(bus, QCA8K_MDIO_MASTER_CTRL, QCA8K_MDIO_MASTER_BUSY); @@ -798,7 +763,7 @@ qca8k_mdio_read(struct qca8k_priv *priv, int phy, int regnum)
exit: /* even if the busy_wait timeouts try to clear the MASTER_EN */ - qca8k_mii_write32(priv, 0x10 | r2, r1, 0); + qca8k_mii_write32(bus, 0x10 | r2, r1, 0);
mutex_unlock(&bus->mdio_lock);
@@ -1968,8 +1933,6 @@ qca8k_sw_probe(struct mdio_device *mdiodev) }
priv->mdio_cache.page = 0xffff; - priv->mdio_cache.lo = 0xffff; - priv->mdio_cache.hi = 0xffff;
/* Check the detected switch id */ ret = qca8k_read_switch_id(priv); diff --git a/drivers/net/dsa/qca/qca8k.h b/drivers/net/dsa/qca/qca8k.h index 0b7a5cb12321..03514f7a20be 100644 --- a/drivers/net/dsa/qca/qca8k.h +++ b/drivers/net/dsa/qca/qca8k.h @@ -375,11 +375,6 @@ struct qca8k_mdio_cache { * mdio writes */ u16 page; -/* lo and hi can also be cached and from Documentation we can skip one - * extra mdio write if lo or hi is didn't change. - */ - u16 lo; - u16 hi; };
struct qca8k_pcs {
On Fri, Dec 16, 2022 at 05:17:19PM +0100, Christian Marangi wrote:
This reverts commit 2481d206fae7884cd07014fd1318e63af35e99eb.
The Documentation is very confusing about the topic. The cache logic for hi and lo is wrong and actually miss some regs to be actually written.
What the Docuemntation actually intended was that it's possible to skip
Just notice that I forgot to fix a typo here! Hope it's not a problem if this can be fixed when merged. If it is I will happly send v2 if the rest of the changes are OK.
writing hi OR lo if half of the reg is not needed to be written or read.
Revert the change in favor of a better and correct implementation.
Reported-by: Ronald Wahl ronald.wahl@raritan.com Signed-off-by: Christian Marangi ansuelsmth@gmail.com Cc: stable@vger.kernel.org # v5.18+
drivers/net/dsa/qca/qca8k-8xxx.c | 61 +++++++------------------------- drivers/net/dsa/qca/qca8k.h | 5 --- 2 files changed, 12 insertions(+), 54 deletions(-)
diff --git a/drivers/net/dsa/qca/qca8k-8xxx.c b/drivers/net/dsa/qca/qca8k-8xxx.c index 46151320b2a8..fbcd5c2b13ae 100644 --- a/drivers/net/dsa/qca/qca8k-8xxx.c +++ b/drivers/net/dsa/qca/qca8k-8xxx.c @@ -36,44 +36,6 @@ qca8k_split_addr(u32 regaddr, u16 *r1, u16 *r2, u16 *page) *page = regaddr & 0x3ff; } -static int -qca8k_set_lo(struct qca8k_priv *priv, int phy_id, u32 regnum, u16 lo) -{
- u16 *cached_lo = &priv->mdio_cache.lo;
- struct mii_bus *bus = priv->bus;
- int ret;
- if (lo == *cached_lo)
return 0;- ret = bus->write(bus, phy_id, regnum, lo);
- if (ret < 0)
dev_err_ratelimited(&bus->dev,"failed to write qca8k 32bit lo register\n");- *cached_lo = lo;
- return 0;
-}
-static int -qca8k_set_hi(struct qca8k_priv *priv, int phy_id, u32 regnum, u16 hi) -{
- u16 *cached_hi = &priv->mdio_cache.hi;
- struct mii_bus *bus = priv->bus;
- int ret;
- if (hi == *cached_hi)
return 0;- ret = bus->write(bus, phy_id, regnum, hi);
- if (ret < 0)
dev_err_ratelimited(&bus->dev,"failed to write qca8k 32bit hi register\n");- *cached_hi = hi;
- return 0;
-}
static int qca8k_mii_read32(struct mii_bus *bus, int phy_id, u32 regnum, u32 *val) { @@ -97,7 +59,7 @@ qca8k_mii_read32(struct mii_bus *bus, int phy_id, u32 regnum, u32 *val) } static void -qca8k_mii_write32(struct qca8k_priv *priv, int phy_id, u32 regnum, u32 val) +qca8k_mii_write32(struct mii_bus *bus, int phy_id, u32 regnum, u32 val) { u16 lo, hi; int ret; @@ -105,9 +67,12 @@ qca8k_mii_write32(struct qca8k_priv *priv, int phy_id, u32 regnum, u32 val) lo = val & 0xffff; hi = (u16)(val >> 16);
- ret = qca8k_set_lo(priv, phy_id, regnum, lo);
- ret = bus->write(bus, phy_id, regnum, lo); if (ret >= 0)
ret = qca8k_set_hi(priv, phy_id, regnum + 1, hi);
ret = bus->write(bus, phy_id, regnum + 1, hi);- if (ret < 0)
dev_err_ratelimited(&bus->dev,"failed to write qca8k 32bit register\n");} static int @@ -442,7 +407,7 @@ qca8k_regmap_write(void *ctx, uint32_t reg, uint32_t val) if (ret < 0) goto exit;
- qca8k_mii_write32(priv, 0x10 | r2, r1, val);
- qca8k_mii_write32(bus, 0x10 | r2, r1, val);
exit: mutex_unlock(&bus->mdio_lock); @@ -475,7 +440,7 @@ qca8k_regmap_update_bits(void *ctx, uint32_t reg, uint32_t mask, uint32_t write_ val &= ~mask; val |= write_val;
- qca8k_mii_write32(priv, 0x10 | r2, r1, val);
- qca8k_mii_write32(bus, 0x10 | r2, r1, val);
exit: mutex_unlock(&bus->mdio_lock); @@ -750,14 +715,14 @@ qca8k_mdio_write(struct qca8k_priv *priv, int phy, int regnum, u16 data) if (ret) goto exit;
- qca8k_mii_write32(priv, 0x10 | r2, r1, val);
- qca8k_mii_write32(bus, 0x10 | r2, r1, val);
ret = qca8k_mdio_busy_wait(bus, QCA8K_MDIO_MASTER_CTRL, QCA8K_MDIO_MASTER_BUSY); exit: /* even if the busy_wait timeouts try to clear the MASTER_EN */
- qca8k_mii_write32(priv, 0x10 | r2, r1, 0);
- qca8k_mii_write32(bus, 0x10 | r2, r1, 0);
mutex_unlock(&bus->mdio_lock); @@ -787,7 +752,7 @@ qca8k_mdio_read(struct qca8k_priv *priv, int phy, int regnum) if (ret) goto exit;
- qca8k_mii_write32(priv, 0x10 | r2, r1, val);
- qca8k_mii_write32(bus, 0x10 | r2, r1, val);
ret = qca8k_mdio_busy_wait(bus, QCA8K_MDIO_MASTER_CTRL, QCA8K_MDIO_MASTER_BUSY); @@ -798,7 +763,7 @@ qca8k_mdio_read(struct qca8k_priv *priv, int phy, int regnum) exit: /* even if the busy_wait timeouts try to clear the MASTER_EN */
- qca8k_mii_write32(priv, 0x10 | r2, r1, 0);
- qca8k_mii_write32(bus, 0x10 | r2, r1, 0);
mutex_unlock(&bus->mdio_lock); @@ -1968,8 +1933,6 @@ qca8k_sw_probe(struct mdio_device *mdiodev) } priv->mdio_cache.page = 0xffff;
- priv->mdio_cache.lo = 0xffff;
- priv->mdio_cache.hi = 0xffff;
/* Check the detected switch id */ ret = qca8k_read_switch_id(priv); diff --git a/drivers/net/dsa/qca/qca8k.h b/drivers/net/dsa/qca/qca8k.h index 0b7a5cb12321..03514f7a20be 100644 --- a/drivers/net/dsa/qca/qca8k.h +++ b/drivers/net/dsa/qca/qca8k.h @@ -375,11 +375,6 @@ struct qca8k_mdio_cache {
- mdio writes
*/ u16 page; -/* lo and hi can also be cached and from Documentation we can skip one
- extra mdio write if lo or hi is didn't change.
- */
- u16 lo;
- u16 hi;
}; struct qca8k_pcs { -- 2.37.2
linux-stable-mirror@lists.linaro.org
-
Christian Marangi