plat/marvell: fix SPD handling in dram port

The DRAM port code issues a dummy write to SPD page-0 i2c address
in order to select this page for the forthcoming read transaction.
If the write buffer length supplied to i2c_write is not zero, this
call is translated to 2 bus transations:

- set the target offset
- write the data to the target

However no actual data should be transferred to SPD page-0 in order
to select it. Actually, the second transation never receives an ACK
from the target device, which caused the following error report:

ERROR:   Status 30 in write transaction

This patch sets the buffer length in page-0 select writes to zero,
leading to bypass the data transfer to the target device.
Issuing the target offset command to SPD page-0 address effectively
selects this page for the read operation.

Change-Id: I4bf8e8c09da115ee875f934bc8fbc9349b995017
Signed-off-by: Konstantin Porotchkin <kostap@marvell.com>
Reviewed-on: https://sj1git1.cavium.com/24387

Tested-by: sa_ip-sw-jenkins <sa_ip-sw-jenkins@marvell.com>
Reviewed-by: Ofer Heifetz <oferh@marvell.com>
Reviewed-by: Moti Buskila <motib@marvell.com>

plat/marvell/armada/a8k/a80x0/board/dram_port.c

@@ -138,7 +138,7 @@ void plat_marvell_dram_update_topology(void)
 		i2c_init((void *)MVEBU_CP0_I2C_BASE);
 
 		/* select SPD memory page 0 to access DRAM configuration */
-		i2c_write(I2C_SPD_P0_ADDR, 0x0, 1, tm->spd_data.all_bytes, 1);
+		i2c_write(I2C_SPD_P0_ADDR, 0x0, 1, tm->spd_data.all_bytes, 0);
 
 		/* read data from spd */
 		i2c_read(I2C_SPD_ADDR, 0x0, 1, tm->spd_data.all_bytes,

plat/marvell/armada/a8k/a80x0_mcbin/board/dram_port.c

@@ -123,7 +123,7 @@ void plat_marvell_dram_update_topology(void)
 		/* initialize the i2c */
 		i2c_init((void *)MVEBU_CP0_I2C_BASE);
 		/* select SPD memory page 0 to access DRAM configuration */
-		i2c_write(I2C_SPD_P0_ADDR, 0x0, 1, tm->spd_data.all_bytes, 1);
+		i2c_write(I2C_SPD_P0_ADDR, 0x0, 1, tm->spd_data.all_bytes, 0);
 		/* read data from spd */
 		i2c_read(I2C_SPD_ADDR, 0x0, 1, tm->spd_data.all_bytes,
 			 sizeof(tm->spd_data.all_bytes));

plat/marvell/armada/a8k/a80x0_puzzle/board/dram_port.c

@@ -132,7 +132,7 @@ void plat_marvell_dram_update_topology(void)
 		/* initialize the MVEBU_AP_I2C_BASE I2C bus */
 		i2c_init((void *)MVEBU_AP_I2C_BASE);
 		/* select SPD memory page 0 to access DRAM configuration */
-		i2c_write(I2C_SPD_P0_ADDR, 0x0, 1, tm->spd_data.all_bytes, 1);
+		i2c_write(I2C_SPD_P0_ADDR, 0x0, 1, tm->spd_data.all_bytes, 0);
 		/* read data from spd */
 		i2c_read(I2C_SPD_ADDR, 0x0, 1, tm->spd_data.all_bytes,
 			 sizeof(tm->spd_data.all_bytes));

plat/marvell/octeontx/otx2/t91/t9130/board/dram_port.c

@@ -149,7 +149,7 @@ void plat_marvell_dram_update_topology(void)
 		i2c_init((void *)MVEBU_CP0_I2C_BASE);
 
 		/* select SPD memory page 0 to access DRAM configuration */
-		i2c_write(I2C_SPD_P0_ADDR, 0x0, 1, tm->spd_data.all_bytes, 1);
+		i2c_write(I2C_SPD_P0_ADDR, 0x0, 1, tm->spd_data.all_bytes, 0);
 
 		/* read data from spd */
 		i2c_read(I2C_SPD_ADDR, 0x0, 1, tm->spd_data.all_bytes,