[PATCH] net: dsa: microchip: KSZ9477 register regmap alignment to 32 bit boundaries

[PATCH] net: dsa: microchip: KSZ9477 register regmap alignment to 32 bit boundaries

[Lukasz Majewski]

The commit (SHA1: 5c844d57aa7894154e49cf2fc648bfe2f1aefc1c) provided code
to apply "Module 6: Certain PHY registers must be written as pairs instead
of singly" errata for KSZ9477 as this chip for certain PHY registers
(0xN120 to 0xN13F, N=1,2,3,4,5) must be accesses as 32 bit words instead
of 16 or 8 bit access.
Otherwise, adjacent registers (no matter if reserved or not) are
overwritten with 0x0.

Without this patch some registers (e.g. 0x113c or 0x1134) required for 32
bit access are out of valid regmap ranges.

As a result, following error is observed and KSZ9477 is not properly
configured:

ksz-switch spi1.0: can't rmw 32bit reg 0x113c: -EIO
ksz-switch spi1.0: can't rmw 32bit reg 0x1134: -EIO
ksz-switch spi1.0 lan1 (uninitialized): failed to connect to PHY: -EIO
ksz-switch spi1.0 lan1 (uninitialized): error -5 setting up PHY for tree 0, switch 0, port 0


The solution is to modify regmap_reg_range to allow accesses with 4 bytes
boundaries.

Signed-off-by: Lukasz Majewski <lukma@denx.de>
---
 drivers/net/dsa/microchip/ksz_common.c | 35 +++++++++++---------------
 1 file changed, 15 insertions(+), 20 deletions(-)

diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
index 813b91a816bb..252bb595602e 100644
--- a/drivers/net/dsa/microchip/ksz_common.c
+++ b/drivers/net/dsa/microchip/ksz_common.c
@@ -635,10 +635,9 @@ static const struct regmap_range ksz9477_valid_regs[] = {
 	regmap_reg_range(0x1030, 0x1030),
 	regmap_reg_range(0x1100, 0x1115),
 	regmap_reg_range(0x111a, 0x111f),
-	regmap_reg_range(0x1122, 0x1127),
-	regmap_reg_range(0x112a, 0x112b),
-	regmap_reg_range(0x1136, 0x1139),
-	regmap_reg_range(0x113e, 0x113f),
+	regmap_reg_range(0x1120, 0x112b),
+	regmap_reg_range(0x1134, 0x113b),
+	regmap_reg_range(0x113c, 0x113f),
 	regmap_reg_range(0x1400, 0x1401),
 	regmap_reg_range(0x1403, 0x1403),
 	regmap_reg_range(0x1410, 0x1417),
@@ -669,10 +668,9 @@ static const struct regmap_range ksz9477_valid_regs[] = {
 	regmap_reg_range(0x2030, 0x2030),
 	regmap_reg_range(0x2100, 0x2115),
 	regmap_reg_range(0x211a, 0x211f),
-	regmap_reg_range(0x2122, 0x2127),
-	regmap_reg_range(0x212a, 0x212b),
-	regmap_reg_range(0x2136, 0x2139),
-	regmap_reg_range(0x213e, 0x213f),
+	regmap_reg_range(0x2120, 0x212b),
+	regmap_reg_range(0x2134, 0x213b),
+	regmap_reg_range(0x213c, 0x213f),
 	regmap_reg_range(0x2400, 0x2401),
 	regmap_reg_range(0x2403, 0x2403),
 	regmap_reg_range(0x2410, 0x2417),
@@ -703,10 +701,9 @@ static const struct regmap_range ksz9477_valid_regs[] = {
 	regmap_reg_range(0x3030, 0x3030),
 	regmap_reg_range(0x3100, 0x3115),
 	regmap_reg_range(0x311a, 0x311f),
-	regmap_reg_range(0x3122, 0x3127),
-	regmap_reg_range(0x312a, 0x312b),
-	regmap_reg_range(0x3136, 0x3139),
-	regmap_reg_range(0x313e, 0x313f),
+	regmap_reg_range(0x3120, 0x312b),
+	regmap_reg_range(0x3134, 0x313b),
+	regmap_reg_range(0x313c, 0x313f),
 	regmap_reg_range(0x3400, 0x3401),
 	regmap_reg_range(0x3403, 0x3403),
 	regmap_reg_range(0x3410, 0x3417),
@@ -737,10 +734,9 @@ static const struct regmap_range ksz9477_valid_regs[] = {
 	regmap_reg_range(0x4030, 0x4030),
 	regmap_reg_range(0x4100, 0x4115),
 	regmap_reg_range(0x411a, 0x411f),
-	regmap_reg_range(0x4122, 0x4127),
-	regmap_reg_range(0x412a, 0x412b),
-	regmap_reg_range(0x4136, 0x4139),
-	regmap_reg_range(0x413e, 0x413f),
+	regmap_reg_range(0x4120, 0x412b),
+	regmap_reg_range(0x4134, 0x413b),
+	regmap_reg_range(0x413c, 0x413f),
 	regmap_reg_range(0x4400, 0x4401),
 	regmap_reg_range(0x4403, 0x4403),
 	regmap_reg_range(0x4410, 0x4417),
@@ -771,10 +767,9 @@ static const struct regmap_range ksz9477_valid_regs[] = {
 	regmap_reg_range(0x5030, 0x5030),
 	regmap_reg_range(0x5100, 0x5115),
 	regmap_reg_range(0x511a, 0x511f),
-	regmap_reg_range(0x5122, 0x5127),
-	regmap_reg_range(0x512a, 0x512b),
-	regmap_reg_range(0x5136, 0x5139),
-	regmap_reg_range(0x513e, 0x513f),
+	regmap_reg_range(0x5120, 0x512b),
+	regmap_reg_range(0x5134, 0x513b),
+	regmap_reg_range(0x513c, 0x513f),
 	regmap_reg_range(0x5400, 0x5401),
 	regmap_reg_range(0x5403, 0x5403),
 	regmap_reg_range(0x5410, 0x5417),
-- 
2.20.1

Re: [PATCH] net: dsa: microchip: KSZ9477 register regmap alignment to 32 bit boundaries

[Simon Horman]

On Thu, Jul 27, 2023 at 10:13:42AM +0200, Lukasz Majewski wrote:
> The commit (SHA1: 5c844d57aa7894154e49cf2fc648bfe2f1aefc1c) provided code
> to apply "Module 6: Certain PHY registers must be written as pairs instead
> of singly" errata for KSZ9477 as this chip for certain PHY registers
> (0xN120 to 0xN13F, N=1,2,3,4,5) must be accesses as 32 bit words instead
> of 16 or 8 bit access.
> Otherwise, adjacent registers (no matter if reserved or not) are
> overwritten with 0x0.
> 
> Without this patch some registers (e.g. 0x113c or 0x1134) required for 32
> bit access are out of valid regmap ranges.
> 
> As a result, following error is observed and KSZ9477 is not properly
> configured:
> 
> ksz-switch spi1.0: can't rmw 32bit reg 0x113c: -EIO
> ksz-switch spi1.0: can't rmw 32bit reg 0x1134: -EIO
> ksz-switch spi1.0 lan1 (uninitialized): failed to connect to PHY: -EIO
> ksz-switch spi1.0 lan1 (uninitialized): error -5 setting up PHY for tree 0, switch 0, port 0
> 
> 
> The solution is to modify regmap_reg_range to allow accesses with 4 bytes
> boundaries.
> 
> Signed-off-by: Lukasz Majewski <lukma@denx.de>

Reviewed-by: Simon Horman <horms@kernel.org>

Re: [PATCH] net: dsa: microchip: KSZ9477 register regmap alignment to 32 bit boundaries

[patchwork-bot+netdevbpf]

Hello:

This patch was applied to netdev/net.git (main)
by David S. Miller <davem@davemloft.net>:

On Thu, 27 Jul 2023 10:13:42 +0200 you wrote:
> The commit (SHA1: 5c844d57aa7894154e49cf2fc648bfe2f1aefc1c) provided code
> to apply "Module 6: Certain PHY registers must be written as pairs instead
> of singly" errata for KSZ9477 as this chip for certain PHY registers
> (0xN120 to 0xN13F, N=1,2,3,4,5) must be accesses as 32 bit words instead
> of 16 or 8 bit access.
> Otherwise, adjacent registers (no matter if reserved or not) are
> overwritten with 0x0.
> 
> [...]

Here is the summary with links:
  - net: dsa: microchip: KSZ9477 register regmap alignment to 32 bit boundaries
    https://git.kernel.org/netdev/net/c/8d7ae22ae9f8

You are awesome, thank you!
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