Re: [PATCH net-next 25/30] net: dsa: mt7530: properly set MT7531_CPU_PMAP
From: Arınç ÜNAL
Date: Sun Jun 04 2023 - 04:26:36 EST
On 26.05.2023 18:51, Vladimir Oltean wrote:
On Mon, May 22, 2023 at 03:15:27PM +0300, arinc9.unal@xxxxxxxxx wrote:
From: Arınç ÜNAL <arinc.unal@xxxxxxxxxx>
Every bit of the CPU port bitmap for MT7531 and the switch on the MT7988
SoC represents a CPU port to trap frames to. Currently only the bit that
corresponds to the first found CPU port is set on the bitmap. Introduce the
MT7531_CPU_PMAP macro to individually set the bits of the CPU port bitmap.
Set the CPU port bitmap for MT7531 and the switch on the MT7988 SoC on
mt753x_cpu_port_enable() which runs on a loop for each CPU port. Add
comments to explain this.
According to the document MT7531 Reference Manual for Development Board
v1.0, the MT7531_CPU_PMAP bits are unset after reset so no need to clear it
beforehand. Since there's currently no public document for the switch on
the MT7988 SoC, I assume this is also the case for this switch.
Tested-by: Arınç ÜNAL <arinc.unal@xxxxxxxxxx>
Signed-off-by: Arınç ÜNAL <arinc.unal@xxxxxxxxxx>
---
Is this supposed to be a bug fix? (incompatibility with past or future
device trees also counts as bugs) If so, it needs a Fixes: tag and to be
targeted towards the "net" tree. Also, the impact of the current behavior
and of the change need to be explained better.
Yes, this fixes a bug for future devicetrees. I will send this to net
with a more detailed explanation, thanks.
drivers/net/dsa/mt7530.c | 15 ++++++++-------
drivers/net/dsa/mt7530.h | 3 ++-
2 files changed, 10 insertions(+), 8 deletions(-)
diff --git a/drivers/net/dsa/mt7530.c b/drivers/net/dsa/mt7530.c
index 58d8738d94d3..0b513e3628fe 100644
--- a/drivers/net/dsa/mt7530.c
+++ b/drivers/net/dsa/mt7530.c
@@ -963,6 +963,13 @@ mt753x_cpu_port_enable(struct dsa_switch *ds, int port)
mt7530_rmw(priv, MT753X_MFC, MT7530_CPU_MASK, MT7530_CPU_EN |
MT7530_CPU_PORT(port));
+ /* Add the CPU port to the CPU port bitmap for MT7531 and the switch on
+ * the MT7988 SoC. Any frames set for trapping to CPU port will be
+ * trapped to the CPU port the user port is affine to.
+ */
+ if (priv->id == ID_MT7531 || priv->id == ID_MT7988)
+ mt7530_set(priv, MT7531_CFC, MT7531_CPU_PMAP(BIT(port)));
+
Stylistically, the existence of an indirect call to priv->info->cpu_port_config()
per switch family is a bit dissonant with an explicit check for device id later
in the same function.
mt753x_cpu_port_enable() is not being called from
priv->info->cpu_port_config() though. I'm not sure how I would do this
without the device ID check here.
/* CPU port gets connected to all user ports of
* the switch.
*/
@@ -2315,15 +2322,9 @@ static int
mt7531_setup_common(struct dsa_switch *ds)
{
struct mt7530_priv *priv = ds->priv;
- struct dsa_port *cpu_dp;
int ret, i;
- /* BPDU to CPU port */
- dsa_switch_for_each_cpu_port(cpu_dp, ds) {
- mt7530_rmw(priv, MT7531_CFC, MT7531_CPU_PMAP_MASK,
- BIT(cpu_dp->index));
- break;
- }
+ /* Trap BPDUs to the CPU port(s) */
mt7530_rmw(priv, MT753X_BPC, MT753X_BPDU_PORT_FW_MASK,
MT753X_BPDU_CPU_ONLY);
diff --git a/drivers/net/dsa/mt7530.h b/drivers/net/dsa/mt7530.h
index 5ebb942b07ef..fd2a2f726b8a 100644
--- a/drivers/net/dsa/mt7530.h
+++ b/drivers/net/dsa/mt7530.h
@@ -53,7 +53,8 @@ enum mt753x_id {
#define MT7531_MIRROR_MASK (0x7 << 16)
#define MT7531_MIRROR_PORT_GET(x) (((x) >> 16) & 0x7)
#define MT7531_MIRROR_PORT_SET(x) (((x) & 0x7) << 16)
-#define MT7531_CPU_PMAP_MASK GENMASK(7, 0)
+#define MT7531_CPU_PMAP(x) ((x) & 0xff)
You can leave this as ((x) & GENMASK(7, 0))
Now that I've read Russell's comment on the previous patch, the below
would be even better?
MT7531_CPU_PMAP(x) FIELD_PREP(MT7531_CPU_PMAP_MASK, x)
+#define MT7531_CPU_PMAP_MASK MT7531_CPU_PMAP(~0)
There's no other user of MT7531_CPU_PMAP_MASK, you can remove this.
Should I do above or remove this?
Arınç