2022-11-08 05:52:19

by Oleksij Rempel

[permalink] [raw]
Subject: [PATCH net-next v3 3/3] net: dsa: microchip: ksz8: add MTU configuration support

Make MTU configurable on KSZ87xx and KSZ88xx series of switches.

Before this patch, pre-configured behavior was different on different
switch series, due to opposite meaning of the same bit:
- KSZ87xx: Reg 4, Bit 1 - if 1, max frame size is 1532; if 0 - 1514
- KSZ88xx: Reg 4, Bit 1 - if 1, max frame size is 1514; if 0 - 1532

Since the code was telling "... SW_LEGAL_PACKET_DISABLE, true)", I
assume, the idea was to set max frame size to 1532.

With this patch, by setting MTU size 1500, both switch series will be
configured to the 1532 frame limit.

This patch was tested on KSZ8873.

Signed-off-by: Oleksij Rempel <[email protected]>
---
drivers/net/dsa/microchip/ksz8.h | 1 +
drivers/net/dsa/microchip/ksz8795.c | 57 ++++++++++++++++++++++++-
drivers/net/dsa/microchip/ksz8795_reg.h | 3 ++
drivers/net/dsa/microchip/ksz_common.c | 7 +++
drivers/net/dsa/microchip/ksz_common.h | 4 ++
5 files changed, 70 insertions(+), 2 deletions(-)

diff --git a/drivers/net/dsa/microchip/ksz8.h b/drivers/net/dsa/microchip/ksz8.h
index 8582b4b67d98..ea05abfbd51d 100644
--- a/drivers/net/dsa/microchip/ksz8.h
+++ b/drivers/net/dsa/microchip/ksz8.h
@@ -57,5 +57,6 @@ int ksz8_reset_switch(struct ksz_device *dev);
int ksz8_switch_detect(struct ksz_device *dev);
int ksz8_switch_init(struct ksz_device *dev);
void ksz8_switch_exit(struct ksz_device *dev);
+int ksz8_change_mtu(struct ksz_device *dev, int port, int mtu);

#endif
diff --git a/drivers/net/dsa/microchip/ksz8795.c b/drivers/net/dsa/microchip/ksz8795.c
index bd3b133e7085..ac03625d427e 100644
--- a/drivers/net/dsa/microchip/ksz8795.c
+++ b/drivers/net/dsa/microchip/ksz8795.c
@@ -76,6 +76,61 @@ int ksz8_reset_switch(struct ksz_device *dev)
return 0;
}

+static int ksz8863_change_mtu(struct ksz_device *dev, int port, int max_frame)
+{
+ u8 ctrl2 = 0;
+
+ if (max_frame <= KSZ8_LEGAL_PACKET_SIZE)
+ ctrl2 |= KSZ8863_LEGAL_PACKET_ENABLE;
+ else if (max_frame > KSZ8863_NORMAL_PACKET_SIZE)
+ ctrl2 |= KSZ8863_HUGE_PACKET_ENABLE;
+
+ return ksz_rmw8(dev, REG_SW_CTRL_2, KSZ8863_LEGAL_PACKET_ENABLE
+ | KSZ8863_HUGE_PACKET_ENABLE, ctrl2);
+}
+
+static int ksz8795_change_mtu(struct ksz_device *dev, int port, int max_frame)
+{
+ u8 ctrl1 = 0, ctrl2 = 0;
+ int ret;
+
+ if (max_frame > KSZ8_LEGAL_PACKET_SIZE)
+ ctrl2 |= SW_LEGAL_PACKET_DISABLE;
+ else if (max_frame > KSZ8863_NORMAL_PACKET_SIZE)
+ ctrl1 |= SW_HUGE_PACKET;
+
+ ret = ksz_rmw8(dev, REG_SW_CTRL_1, SW_HUGE_PACKET, ctrl1);
+ if (ret)
+ return ret;
+
+ return ksz_rmw8(dev, REG_SW_CTRL_2, SW_LEGAL_PACKET_DISABLE, ctrl2);
+}
+
+int ksz8_change_mtu(struct ksz_device *dev, int port, int mtu)
+{
+ u16 frame_size, max_frame = 0;
+ int i;
+
+ frame_size = mtu + VLAN_ETH_HLEN + ETH_FCS_LEN;
+
+ /* Cache the per-port MTU setting */
+ dev->ports[port].max_frame = frame_size;
+
+ for (i = 0; i < dev->info->port_cnt; i++)
+ max_frame = max(max_frame, dev->ports[i].max_frame);
+
+ switch (dev->chip_id) {
+ case KSZ8795_CHIP_ID:
+ case KSZ8794_CHIP_ID:
+ case KSZ8765_CHIP_ID:
+ return ksz8795_change_mtu(dev, port, max_frame);
+ case KSZ8830_CHIP_ID:
+ return ksz8863_change_mtu(dev, port, max_frame);
+ }
+
+ return -EOPNOTSUPP;
+}
+
static void ksz8795_set_prio_queue(struct ksz_device *dev, int port, int queue)
{
u8 hi, lo;
@@ -1233,8 +1288,6 @@ void ksz8_config_cpu_port(struct dsa_switch *ds)
masks = dev->info->masks;
regs = dev->info->regs;

- /* Switch marks the maximum frame with extra byte as oversize. */
- ksz_cfg(dev, REG_SW_CTRL_2, SW_LEGAL_PACKET_DISABLE, true);
ksz_cfg(dev, regs[S_TAIL_TAG_CTRL], masks[SW_TAIL_TAG_ENABLE], true);

p = &dev->ports[dev->cpu_port];
diff --git a/drivers/net/dsa/microchip/ksz8795_reg.h b/drivers/net/dsa/microchip/ksz8795_reg.h
index 77487d611824..7a57c6088f80 100644
--- a/drivers/net/dsa/microchip/ksz8795_reg.h
+++ b/drivers/net/dsa/microchip/ksz8795_reg.h
@@ -48,6 +48,9 @@
#define NO_EXC_COLLISION_DROP BIT(3)
#define SW_LEGAL_PACKET_DISABLE BIT(1)

+#define KSZ8863_HUGE_PACKET_ENABLE BIT(2)
+#define KSZ8863_LEGAL_PACKET_ENABLE BIT(1)
+
#define REG_SW_CTRL_3 0x05
#define WEIGHTED_FAIR_QUEUE_ENABLE BIT(3)

diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
index 486ad03d0acf..188c66145df7 100644
--- a/drivers/net/dsa/microchip/ksz_common.c
+++ b/drivers/net/dsa/microchip/ksz_common.c
@@ -172,6 +172,7 @@ static const struct ksz_dev_ops ksz8_dev_ops = {
.reset = ksz8_reset_switch,
.init = ksz8_switch_init,
.exit = ksz8_switch_exit,
+ .change_mtu = ksz8_change_mtu,
};

static void ksz9477_phylink_mac_link_up(struct ksz_device *dev, int port,
@@ -2473,6 +2474,12 @@ static int ksz_max_mtu(struct dsa_switch *ds, int port)
struct ksz_device *dev = ds->priv;

switch (dev->chip_id) {
+ case KSZ8795_CHIP_ID:
+ case KSZ8794_CHIP_ID:
+ case KSZ8765_CHIP_ID:
+ return KSZ8795_HUGE_PACKET_SIZE - VLAN_ETH_HLEN - ETH_FCS_LEN;
+ case KSZ8830_CHIP_ID:
+ return KSZ8863_HUGE_PACKET_SIZE - VLAN_ETH_HLEN - ETH_FCS_LEN;
case KSZ8563_CHIP_ID:
case KSZ9477_CHIP_ID:
case KSZ9567_CHIP_ID:
diff --git a/drivers/net/dsa/microchip/ksz_common.h b/drivers/net/dsa/microchip/ksz_common.h
index 85ce6ec573ba..4a43a2cf7017 100644
--- a/drivers/net/dsa/microchip/ksz_common.h
+++ b/drivers/net/dsa/microchip/ksz_common.h
@@ -589,6 +589,10 @@ static inline int is_lan937x(struct ksz_device *dev)

#define PORT_SRC_PHY_INT 1

+#define KSZ8795_HUGE_PACKET_SIZE 2000
+#define KSZ8863_HUGE_PACKET_SIZE 1916
+#define KSZ8863_NORMAL_PACKET_SIZE 1536
+#define KSZ8_LEGAL_PACKET_SIZE 1518
#define KSZ9477_MAX_FRAME_SIZE 9000

/* Regmap tables generation */
--
2.30.2



2022-11-08 07:26:59

by Arun Ramadoss

[permalink] [raw]
Subject: Re: [PATCH net-next v3 3/3] net: dsa: microchip: ksz8: add MTU configuration support

On Tue, 2022-11-08 at 06:43 +0100, Oleksij Rempel wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you
> know the content is safe
>
> Make MTU configurable on KSZ87xx and KSZ88xx series of switches.
>
> Before this patch, pre-configured behavior was different on different
> switch series, due to opposite meaning of the same bit:
> - KSZ87xx: Reg 4, Bit 1 - if 1, max frame size is 1532; if 0 - 1514
> - KSZ88xx: Reg 4, Bit 1 - if 1, max frame size is 1514; if 0 - 1532
>
> Since the code was telling "... SW_LEGAL_PACKET_DISABLE, true)", I
> assume, the idea was to set max frame size to 1532.
>
> With this patch, by setting MTU size 1500, both switch series will be
> configured to the 1532 frame limit.
>
> This patch was tested on KSZ8873.

Acked-by: Arun Ramadoss <[email protected]>

>
> Signed-off-by: Oleksij Rempel <[email protected]>
> ---
> drivers/net/dsa/microchip/ksz8.h | 1 +
> drivers/net/dsa/microchip/ksz8795.c | 57
> ++++++++++++++++++++++++-
> drivers/net/dsa/microchip/ksz8795_reg.h | 3 ++
> drivers/net/dsa/microchip/ksz_common.c | 7 +++
> drivers/net/dsa/microchip/ksz_common.h | 4 ++
> 5 files changed, 70 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/dsa/microchip/ksz8.h
> b/drivers/net/dsa/microchip/ksz8.h
> index 8582b4b67d98..ea05abfbd51d 100644
> --- a/drivers/net/dsa/microchip/ksz8.h
> +++ b/drivers/net/dsa/microchip/ksz8.h
> @@ -57,5 +57,6 @@ int ksz8_reset_switch(struct ksz_device *dev);
> int ksz8_switch_detect(struct ksz_device *dev);
> int ksz8_switch_init(struct ksz_device *dev);
> void ksz8_switch_exit(struct ksz_device *dev);
> +int ksz8_change_mtu(struct ksz_device *dev, int port, int mtu);
>
> #endif
> diff --git a/drivers/net/dsa/microchip/ksz8795.c
> b/drivers/net/dsa/microchip/ksz8795.c
> index bd3b133e7085..ac03625d427e 100644
> --- a/drivers/net/dsa/microchip/ksz8795.c
> +++ b/drivers/net/dsa/microchip/ksz8795.c
> @@ -76,6 +76,61 @@ int ksz8_reset_switch(struct ksz_device *dev)
> return 0;
> }
>
> +static int ksz8863_change_mtu(struct ksz_device *dev, int port, int
> max_frame)
> +{
> + u8 ctrl2 = 0;
> +
> + if (max_frame <= KSZ8_LEGAL_PACKET_SIZE)
> + ctrl2 |= KSZ8863_LEGAL_PACKET_ENABLE;
> + else if (max_frame > KSZ8863_NORMAL_PACKET_SIZE)
> + ctrl2 |= KSZ8863_HUGE_PACKET_ENABLE;
> +
> + return ksz_rmw8(dev, REG_SW_CTRL_2,
> KSZ8863_LEGAL_PACKET_ENABLE
> + | KSZ8863_HUGE_PACKET_ENABLE, ctrl2);
> +}
> +
> +static int ksz8795_change_mtu(struct ksz_device *dev, int port, int
> max_frame)
> +{
> + u8 ctrl1 = 0, ctrl2 = 0;
> + int ret;
> +
> + if (max_frame > KSZ8_LEGAL_PACKET_SIZE)
> + ctrl2 |= SW_LEGAL_PACKET_DISABLE;
> + else if (max_frame > KSZ8863_NORMAL_PACKET_SIZE)
> + ctrl1 |= SW_HUGE_PACKET;
> +
> + ret = ksz_rmw8(dev, REG_SW_CTRL_1, SW_HUGE_PACKET, ctrl1);
> + if (ret)
> + return ret;
> +
> + return ksz_rmw8(dev, REG_SW_CTRL_2, SW_LEGAL_PACKET_DISABLE,
> ctrl2);
> +}
> +
> +int ksz8_change_mtu(struct ksz_device *dev, int port, int mtu)
> +{
> + u16 frame_size, max_frame = 0;
> + int i;
> +
> + frame_size = mtu + VLAN_ETH_HLEN + ETH_FCS_LEN;
> +
> + /* Cache the per-port MTU setting */
> + dev->ports[port].max_frame = frame_size;
> +
> + for (i = 0; i < dev->info->port_cnt; i++)
> + max_frame = max(max_frame, dev->ports[i].max_frame);
> +
> + switch (dev->chip_id) {
> + case KSZ8795_CHIP_ID:
> + case KSZ8794_CHIP_ID:
> + case KSZ8765_CHIP_ID:
> + return ksz8795_change_mtu(dev, port, max_frame);
> + case KSZ8830_CHIP_ID:
> + return ksz8863_change_mtu(dev, port, max_frame);
> + }
> +
> + return -EOPNOTSUPP;
> +}
> +
> static void ksz8795_set_prio_queue(struct ksz_device *dev, int port,
> int queue)
> {
> u8 hi, lo;
> @@ -1233,8 +1288,6 @@ void ksz8_config_cpu_port(struct dsa_switch
> *ds)
> masks = dev->info->masks;
> regs = dev->info->regs;
>
> - /* Switch marks the maximum frame with extra byte as
> oversize. */
> - ksz_cfg(dev, REG_SW_CTRL_2, SW_LEGAL_PACKET_DISABLE, true);
> ksz_cfg(dev, regs[S_TAIL_TAG_CTRL],
> masks[SW_TAIL_TAG_ENABLE], true);
>
> p = &dev->ports[dev->cpu_port];
> diff --git a/drivers/net/dsa/microchip/ksz8795_reg.h
> b/drivers/net/dsa/microchip/ksz8795_reg.h
> index 77487d611824..7a57c6088f80 100644
> --- a/drivers/net/dsa/microchip/ksz8795_reg.h
> +++ b/drivers/net/dsa/microchip/ksz8795_reg.h
> @@ -48,6 +48,9 @@
> #define NO_EXC_COLLISION_DROP BIT(3)
> #define SW_LEGAL_PACKET_DISABLE BIT(1)
>
> +#define KSZ8863_HUGE_PACKET_ENABLE BIT(2)
> +#define KSZ8863_LEGAL_PACKET_ENABLE BIT(1)
> +
> #define REG_SW_CTRL_3 0x05
> #define WEIGHTED_FAIR_QUEUE_ENABLE BIT(3)
>
> diff --git a/drivers/net/dsa/microchip/ksz_common.c
> b/drivers/net/dsa/microchip/ksz_common.c
> index 486ad03d0acf..188c66145df7 100644
> --- a/drivers/net/dsa/microchip/ksz_common.c
> +++ b/drivers/net/dsa/microchip/ksz_common.c
> @@ -172,6 +172,7 @@ static const struct ksz_dev_ops ksz8_dev_ops = {
> .reset = ksz8_reset_switch,
> .init = ksz8_switch_init,
> .exit = ksz8_switch_exit,
> + .change_mtu = ksz8_change_mtu,
> };
>
> static void ksz9477_phylink_mac_link_up(struct ksz_device *dev, int
> port,
> @@ -2473,6 +2474,12 @@ static int ksz_max_mtu(struct dsa_switch *ds,
> int port)
> struct ksz_device *dev = ds->priv;
>
> switch (dev->chip_id) {
> + case KSZ8795_CHIP_ID:
> + case KSZ8794_CHIP_ID:
> + case KSZ8765_CHIP_ID:
> + return KSZ8795_HUGE_PACKET_SIZE - VLAN_ETH_HLEN -
> ETH_FCS_LEN;
> + case KSZ8830_CHIP_ID:
> + return KSZ8863_HUGE_PACKET_SIZE - VLAN_ETH_HLEN -
> ETH_FCS_LEN;
> case KSZ8563_CHIP_ID:
> case KSZ9477_CHIP_ID:
> case KSZ9567_CHIP_ID:
> diff --git a/drivers/net/dsa/microchip/ksz_common.h
> b/drivers/net/dsa/microchip/ksz_common.h
> index 85ce6ec573ba..4a43a2cf7017 100644
> --- a/drivers/net/dsa/microchip/ksz_common.h
> +++ b/drivers/net/dsa/microchip/ksz_common.h
> @@ -589,6 +589,10 @@ static inline int is_lan937x(struct ksz_device
> *dev)
>
> #define PORT_SRC_PHY_INT 1
>
> +#define KSZ8795_HUGE_PACKET_SIZE 2000
> +#define KSZ8863_HUGE_PACKET_SIZE 1916
> +#define KSZ8863_NORMAL_PACKET_SIZE 1536
> +#define KSZ8_LEGAL_PACKET_SIZE 1518
> #define KSZ9477_MAX_FRAME_SIZE 9000
>
> /* Regmap tables generation */
> --
> 2.30.2
>

2022-11-08 09:57:13

by Vladimir Oltean

[permalink] [raw]
Subject: Re: [PATCH net-next v3 3/3] net: dsa: microchip: ksz8: add MTU configuration support

On Tue, Nov 08, 2022 at 06:43:36AM +0100, Oleksij Rempel wrote:
> +static int ksz8863_change_mtu(struct ksz_device *dev, int port, int max_frame)

Don't pass "int port" if you're not going to use it.

> +{
> + u8 ctrl2 = 0;
> +
> + if (max_frame <= KSZ8_LEGAL_PACKET_SIZE)
> + ctrl2 |= KSZ8863_LEGAL_PACKET_ENABLE;
> + else if (max_frame > KSZ8863_NORMAL_PACKET_SIZE)
> + ctrl2 |= KSZ8863_HUGE_PACKET_ENABLE;
> +
> + return ksz_rmw8(dev, REG_SW_CTRL_2, KSZ8863_LEGAL_PACKET_ENABLE
> + | KSZ8863_HUGE_PACKET_ENABLE, ctrl2);

Coding conventions are to not start a new line with an operator, but to
put it at the end of the previous line:

return ksz_rmw8(dev, REG_SW_CTRL_2, KSZ8863_LEGAL_PACKET_ENABLE |
KSZ8863_HUGE_PACKET_ENABLE, ctrl2);

> +}
> +
> +static int ksz8795_change_mtu(struct ksz_device *dev, int port, int max_frame)

Same.

> +{
> + u8 ctrl1 = 0, ctrl2 = 0;
> + int ret;
> +
> + if (max_frame > KSZ8_LEGAL_PACKET_SIZE)
> + ctrl2 |= SW_LEGAL_PACKET_DISABLE;
> + else if (max_frame > KSZ8863_NORMAL_PACKET_SIZE)
> + ctrl1 |= SW_HUGE_PACKET;
> +
> + ret = ksz_rmw8(dev, REG_SW_CTRL_1, SW_HUGE_PACKET, ctrl1);
> + if (ret)
> + return ret;
> +
> + return ksz_rmw8(dev, REG_SW_CTRL_2, SW_LEGAL_PACKET_DISABLE, ctrl2);
> +}
> +
> +int ksz8_change_mtu(struct ksz_device *dev, int port, int mtu)
> +{
> + u16 frame_size, max_frame = 0;
> + int i;
> +
> + frame_size = mtu + VLAN_ETH_HLEN + ETH_FCS_LEN;
> +
> + /* Cache the per-port MTU setting */
> + dev->ports[port].max_frame = frame_size;
> +
> + for (i = 0; i < dev->info->port_cnt; i++)
> + max_frame = max(max_frame, dev->ports[i].max_frame);

You can do what other switches do, and instead of caching into an array,
"return 0" for everything except the CPU port. The CPU port will always
be programmed with the largest MTU.

> +
> + switch (dev->chip_id) {
> + case KSZ8795_CHIP_ID:
> + case KSZ8794_CHIP_ID:
> + case KSZ8765_CHIP_ID:
> + return ksz8795_change_mtu(dev, port, max_frame);
> + case KSZ8830_CHIP_ID:
> + return ksz8863_change_mtu(dev, port, max_frame);
> + }
> +
> + return -EOPNOTSUPP;
> +}
> +