[PATCH linux dev-4.7] drivers/fsi: Adjust slave ID based on address in command send

[Joel Stanley]

On Thu, Feb 9, 2017 at 10:03 AM, Christopher Bostic
<cbostic at linux.vnet.ibm.com> wrote:
> In order to access slave address ranges > 0x1FFFFF the slave ID
> must be adjusted accordingly in the command encoding:
>
> ID 0: 0x00000000 - 0x001FFFFF
> ID 1: 0x00200000 - 0x003FFFFF
> ID 2: 0x00400000 - 0x005FFFFF
> ID 3: 0x00600000 - 0x007FFFFF

Alistair and Eddie, can I please get an ack from both of you on this?

>
> Signed-off-by: Christopher Bostic <cbostic at linux.vnet.ibm.com>
> ---
>  drivers/fsi/fsi-master-gpio.c | 20 ++++++++++++++++----
>  1 file changed, 16 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/fsi/fsi-master-gpio.c b/drivers/fsi/fsi-master-gpio.c
> index 73d9985..428f3db 100644
> --- a/drivers/fsi/fsi-master-gpio.c
> +++ b/drivers/fsi/fsi-master-gpio.c
> @@ -30,7 +30,9 @@
>  #define        FSI_GPIO_CMD_READ       0x0400000000000000ULL
>  #define        FSI_GPIO_CMD_SLAVE_MASK 0xC000000000000000ULL
>  #define        FSI_GPIO_CMD_ADDR_SHIFT 37
> -#define        FSI_GPIO_CMD_ADDR_MASK  0x001FFFFF
> +#define        FSI_GPIO_CMD_ADR8_MASK  0x001FFFFF
> +#define        FSI_GPIO_CMD_ADR16_MASK 0x001FFFFE
> +#define        FSI_GPIO_CMD_ADR32_MASK 0x001FFFFC
>  #define        FSI_GPIO_CMD_SLV_SHIFT  62
>  #define        FSI_GPIO_CMD_SIZE_16    0x0000001000000000ULL
>  #define        FSI_GPIO_CMD_SIZE_32    0x0000003000000000ULL
> @@ -40,6 +42,9 @@
>  #define        FSI_GPIO_CMD_DFLT_LEN   28
>  #define        FSI_GPIO_CMD_CRC_SHIFT  60
>
> +#define        FSI_SLAVE_SHIFT         21
> +#define        FSI_SLAVE_MASK          0x3
> +
>  /* Bus errors */
>  #define        FSI_GPIO_ERR_BUSY       1       /* Slave stuck in busy state */
>  #define        FSI_GPIO_RESP_ERRA      2       /* Any (misc) Error */
> @@ -301,15 +306,17 @@ static void build_abs_ar_command(struct fsi_gpio_msg *cmd, uint64_t mode,
>                 const void *data)
>  {
>         uint8_t crc;
> +       uint32_t addr_mask;
>
>         cmd->bits = FSI_GPIO_CMD_DFLT_LEN;
>         cmd->msg = FSI_GPIO_CMD_DEFAULT;
>         cmd->msg |= mode;
> -       cmd->msg &= ~FSI_GPIO_CMD_SLAVE_MASK;
> +       if (!slave)
> +               slave = (addr >> FSI_SLAVE_SHIFT) & FSI_SLAVE_MASK;
>         cmd->msg |= (((uint64_t)slave) << FSI_GPIO_CMD_SLV_SHIFT);
> -       addr &= FSI_GPIO_CMD_ADDR_MASK;
> -       cmd->msg |= (((uint64_t)addr) << FSI_GPIO_CMD_ADDR_SHIFT);
> +
>         if (size == sizeof(uint8_t)) {
> +               addr_mask = FSI_GPIO_CMD_ADR8_MASK;
>                 if (data) {
>                         uint8_t cmd_data = *((uint8_t *)data);
>
> @@ -317,6 +324,7 @@ static void build_abs_ar_command(struct fsi_gpio_msg *cmd, uint64_t mode,
>                                 ((uint64_t)cmd_data) << FSI_GPIO_CMD_DT8_SHIFT;
>                 }
>         } else if (size == sizeof(uint16_t)) {
> +               addr_mask = FSI_GPIO_CMD_ADR16_MASK;
>                 cmd->msg |= FSI_GPIO_CMD_SIZE_16;
>                 if (data) {
>                         uint16_t cmd_data;
> @@ -326,6 +334,7 @@ static void build_abs_ar_command(struct fsi_gpio_msg *cmd, uint64_t mode,
>                                 ((uint64_t)cmd_data) << FSI_GPIO_CMD_DT16_SHIFT;
>                 }
>         } else {
> +               addr_mask = FSI_GPIO_CMD_ADR32_MASK;
>                 cmd->msg |= FSI_GPIO_CMD_SIZE_32;
>                 if (data) {
>                         uint32_t cmd_data;
> @@ -336,6 +345,9 @@ static void build_abs_ar_command(struct fsi_gpio_msg *cmd, uint64_t mode,
>                 }
>         }
>
> +       addr &= addr_mask;
> +       cmd->msg |= (((uint64_t)addr) << FSI_GPIO_CMD_ADDR_SHIFT);
> +
>         if (mode == FSI_GPIO_CMD_WRITE)
>                 cmd->bits += (8 * size);
>
> --
> 1.8.2.2
>