Re: [PATCH v14 07/10] soc: mediatek: cmdq: define the instruction struct

houlong wei
2019-08-30T02:24:04Z

On Thu, 2019-08-29 at 09:48 +0800, Bibby Hsieh wrote:
> Define an instruction structure for gce driver to append command.
> This structure can make the client's code more readability.
>
> Signed-off-by: Bibby Hsieh <bibby.hsieh@mediatek.com>
> Reviewed-by: CK Hu <ck.hu@mediatek.com>
> Reviewed-by: Houlong Wei <houlong.wei@mediatek.com>
> ---
> drivers/soc/mediatek/mtk-cmdq-helper.c | 77 ++++++++++++++++--------
> include/linux/mailbox/mtk-cmdq-mailbox.h | 10 +++
> 2 files changed, 61 insertions(+), 26 deletions(-)
>
> diff --git a/drivers/soc/mediatek/mtk-cmdq-helper.c b/drivers/soc/mediatek/mtk-cmdq-helper.c
> index 7aa0517ff2f3..9472526ab076 100644
> --- a/drivers/soc/mediatek/mtk-cmdq-helper.c
> +++ b/drivers/soc/mediatek/mtk-cmdq-helper.c
> @@ -9,12 +9,24 @@
> #include <linux/mailbox_controller.h>
> #include <linux/soc/mediatek/mtk-cmdq.h>
>
> -#define CMDQ_ARG_A_WRITE_MASK 0xffff
> #define CMDQ_WRITE_ENABLE_MASK BIT(0)
> #define CMDQ_EOC_IRQ_EN BIT(0)
> #define CMDQ_EOC_CMD ((u64)((CMDQ_CODE_EOC << CMDQ_OP_CODE_SHIFT)) \
> << 32 | CMDQ_EOC_IRQ_EN)
>
> +struct cmdq_instruction {
> + union {
> + u32 value;
> + u32 mask;
> + };
> + union {
> + u16 offset;
> + u16 event;
> + };
> + u8 subsys;
> + u8 op;
> +};
> +
> static void cmdq_client_timeout(struct timer_list *t)
> {
> struct cmdq_client *client = from_timer(client, t, timer);
> @@ -110,10 +122,10 @@ void cmdq_pkt_destroy(struct cmdq_pkt *pkt)
> }
> EXPORT_SYMBOL(cmdq_pkt_destroy);
>
> -static int cmdq_pkt_append_command(struct cmdq_pkt *pkt, enum cmdq_code code,
> - u32 arg_a, u32 arg_b)
> +static int cmdq_pkt_append_command(struct cmdq_pkt *pkt,
> + struct cmdq_instruction inst)

Can we use 'struct cmdq_instruction *inst' instead of 'struct
cmdq_instruction inst' to reduce stack memory consumption a bit?

> {
> - u64 *cmd_ptr;
> + struct cmdq_instruction *cmd_ptr;
>
> if (unlikely(pkt->cmd_buf_size + CMDQ_INST_SIZE > pkt->buf_size)) {
> /*
> @@ -129,8 +141,9 @@ static int cmdq_pkt_append_command(struct cmdq_pkt *pkt, enum cmdq_code code,
> __func__, (u32)pkt->buf_size);
> return -ENOMEM;
> }
> +
> cmd_ptr = pkt->va_base + pkt->cmd_buf_size;
> - (*cmd_ptr) = (u64)((code << CMDQ_OP_CODE_SHIFT) | arg_a) << 32 | arg_b;
> + *cmd_ptr = inst;
> pkt->cmd_buf_size += CMDQ_INST_SIZE;
>
> return 0;
> @@ -138,24 +151,31 @@ static int cmdq_pkt_append_command(struct cmdq_pkt *pkt, enum cmdq_code code,
>
> int cmdq_pkt_write(struct cmdq_pkt *pkt, u8 subsys, u16 offset, u32 value)
> {
> - u32 arg_a = (offset & CMDQ_ARG_A_WRITE_MASK) |
> - (subsys << CMDQ_SUBSYS_SHIFT);
> + struct cmdq_instruction inst;
> +
> + inst.op = CMDQ_CODE_WRITE;
> + inst.value = value;
> + inst.offset = offset;
> + inst.subsys = subsys;
>
> - return cmdq_pkt_append_command(pkt, CMDQ_CODE_WRITE, arg_a, value);
> + return cmdq_pkt_append_command(pkt, inst);
> }
> EXPORT_SYMBOL(cmdq_pkt_write);
>
> int cmdq_pkt_write_mask(struct cmdq_pkt *pkt, u8 subsys,
> u16 offset, u32 value, u32 mask)
> {
> - u32 offset_mask = offset;
> + struct cmdq_instruction inst = { {0} };
> + u16 offset_mask = offset;
> int err = 0;
>
> if (mask != 0xffffffff) {
> - err = cmdq_pkt_append_command(pkt, CMDQ_CODE_MASK, 0, ~mask);
> + inst.op = CMDQ_CODE_MASK;
> + inst.mask = ~mask;
> + err = cmdq_pkt_append_command(pkt, inst);
> offset_mask |= CMDQ_WRITE_ENABLE_MASK;
> }
> - err |= cmdq_pkt_write(pkt, value, subsys, offset_mask);
> + err |= cmdq_pkt_write(pkt, subsys, offset_mask, value);
>
> return err;
> }
> @@ -163,43 +183,48 @@ EXPORT_SYMBOL(cmdq_pkt_write_mask);
>
> int cmdq_pkt_wfe(struct cmdq_pkt *pkt, u16 event)
> {
> - u32 arg_b;
> + struct cmdq_instruction inst = { {0} };
>
> if (event >= CMDQ_MAX_EVENT)
> return -EINVAL;
>
> - /*
> - * WFE arg_b
> - * bit 0-11: wait value
> - * bit 15: 1 - wait, 0 - no wait
> - * bit 16-27: update value
> - * bit 31: 1 - update, 0 - no update
> - */
> - arg_b = CMDQ_WFE_UPDATE | CMDQ_WFE_WAIT | CMDQ_WFE_WAIT_VALUE;
> + inst.op = CMDQ_CODE_WFE;
> + inst.value = CMDQ_WFE_OPTION;
> + inst.event = event;
>
> - return cmdq_pkt_append_command(pkt, CMDQ_CODE_WFE, event, arg_b);
> + return cmdq_pkt_append_command(pkt, inst);
> }
> EXPORT_SYMBOL(cmdq_pkt_wfe);
>
> int cmdq_pkt_clear_event(struct cmdq_pkt *pkt, u16 event)
> {
> + struct cmdq_instruction inst = { {0} };
> +
> if (event >= CMDQ_MAX_EVENT)
> return -EINVAL;
>
> - return cmdq_pkt_append_command(pkt, CMDQ_CODE_WFE, event,
> - CMDQ_WFE_UPDATE);
> + inst.op = CMDQ_CODE_WFE;
> + inst.value = CMDQ_WFE_UPDATE;
> + inst.event = event;
> +
> + return cmdq_pkt_append_command(pkt, inst);
> }
> EXPORT_SYMBOL(cmdq_pkt_clear_event);
>
> static int cmdq_pkt_finalize(struct cmdq_pkt *pkt)
> {
> - int err;
> + struct cmdq_instruction inst = { {0} };
> + int err = 0;
>
> /* insert EOC and generate IRQ for each command iteration */
> - err = cmdq_pkt_append_command(pkt, CMDQ_CODE_EOC, 0, CMDQ_EOC_IRQ_EN);
> + inst.op = CMDQ_CODE_EOC;
> + inst.value = CMDQ_EOC_IRQ_EN;
> + err = cmdq_pkt_append_command(pkt, inst);
>
> /* JUMP to end */
> - err |= cmdq_pkt_append_command(pkt, CMDQ_CODE_JUMP, 0, CMDQ_JUMP_PASS);
> + inst.op = CMDQ_CODE_JUMP;
> + inst.value = CMDQ_JUMP_PASS;
> + err |= cmdq_pkt_append_command(pkt, inst);
>
> return err;
> }
> diff --git a/include/linux/mailbox/mtk-cmdq-mailbox.h b/include/linux/mailbox/mtk-cmdq-mailbox.h
> index e6f54ef6698b..678760548791 100644
> --- a/include/linux/mailbox/mtk-cmdq-mailbox.h
> +++ b/include/linux/mailbox/mtk-cmdq-mailbox.h
> @@ -20,6 +20,16 @@
> #define CMDQ_WFE_WAIT BIT(15)
> #define CMDQ_WFE_WAIT_VALUE 0x1
>
> +/*
> + * WFE arg_b
> + * bit 0-11: wait value
> + * bit 15: 1 - wait, 0 - no wait
> + * bit 16-27: update value
> + * bit 31: 1 - update, 0 - no update
> + */
> +#define CMDQ_WFE_OPTION (CMDQ_WFE_UPDATE | CMDQ_WFE_WAIT | \
> + CMDQ_WFE_WAIT_VALUE)
> +
> /** cmdq event maximum */
> #define CMDQ_MAX_EVENT 0x3ff
>