Subject: [net-next 13/15] net/mlx5: Query the maximum MCIA register read size from firmware

From: Saeed Mahameed <[email-masked]>
Date: Thu, 10 Mar 2022 23:40:29 -0800

From: Gal Pressman <[email-masked]>

The MCIA register supports either 12 or 32 dwords, use the correct value
by querying the capability from the MCAM register.

Signed-off-by: Gal Pressman <[email-masked]>
Reviewed-by: Maxim Mikityanskiy <[email-masked]>
Signed-off-by: Saeed Mahameed <[email-masked]>
---
 drivers/net/ethernet/mellanox/mlx5/core/port.c | 8 +++++++-
 include/linux/mlx5/mlx5_ifc.h                  | 4 +++-
 include/linux/mlx5/port.h                      | 1 -
 3 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/port.c b/drivers/net/ethernet/mellanox/mlx5/core/port.c
index 289b29a23418..418ab777f6e8 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/port.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/port.c
@@ -365,6 +365,12 @@ static void mlx5_sfp_eeprom_params_set(u16 *i2c_addr, int *page_num, u16 *offset
 	*offset -= MLX5_EEPROM_PAGE_LENGTH;
 }
 
+static int mlx5_mcia_max_bytes(struct mlx5_core_dev *dev)
+{
+	/* mcia supports either 12 dwords or 32 dwords */
+	return (MLX5_CAP_MCAM_FEATURE(dev, mcia_32dwords) ? 32 : 12) * sizeof(u32);
+}
+
 static int mlx5_query_mcia(struct mlx5_core_dev *dev,
 			   struct mlx5_module_eeprom_query_params *params, u8 *data)
 {
@@ -374,7 +380,7 @@ static int mlx5_query_mcia(struct mlx5_core_dev *dev,
 	void *ptr;
 	u16 size;
 
-	size = min_t(int, params->size, MLX5_EEPROM_MAX_BYTES);
+	size = min_t(int, params->size, mlx5_mcia_max_bytes(dev));
 
 	MLX5_SET(mcia_reg, in, l, 0);
 	MLX5_SET(mcia_reg, in, size, size);
diff --git a/include/linux/mlx5/mlx5_ifc.h b/include/linux/mlx5/mlx5_ifc.h
index 318fae4b3560..745107ff681d 100644
--- a/include/linux/mlx5/mlx5_ifc.h
+++ b/include/linux/mlx5/mlx5_ifc.h
@@ -9691,7 +9691,9 @@ struct mlx5_ifc_pcam_reg_bits {
 };
 
 struct mlx5_ifc_mcam_enhanced_features_bits {
-	u8         reserved_at_0[0x6a];
+	u8         reserved_at_0[0x5d];
+	u8         mcia_32dwords[0x1];
+	u8         reserved_at_5e[0xc];
 	u8         reset_state[0x1];
 	u8         ptpcyc2realtime_modify[0x1];
 	u8         reserved_at_6c[0x2];
diff --git a/include/linux/mlx5/port.h b/include/linux/mlx5/port.h
index 77ea4f9c5265..402413b3e914 100644
--- a/include/linux/mlx5/port.h
+++ b/include/linux/mlx5/port.h
@@ -56,7 +56,6 @@ enum mlx5_an_status {
 	MLX5_AN_LINK_DOWN   = 4,
 };
 
-#define MLX5_EEPROM_MAX_BYTES			32
 #define MLX5_EEPROM_IDENTIFIER_BYTE_MASK	0x000000ff
 #define MLX5_I2C_ADDR_LOW		0x50
 #define MLX5_I2C_ADDR_HIGH		0x51
-- 
2.35.1