Re: [PATCH v4 08/12] soc: mediatek: cmdq: add packet encoder function

From: CK Hu
Date: Mon Apr 22 2019 - 01:33:16 EST


Hi, Bibby:

On Mon, 2019-04-15 at 20:58 +0800, Bibby Hsieh wrote:
> Implement a function can encode the GCE instructions
>
> Signed-off-by: Bibby Hsieh <bibby.hsieh@xxxxxxxxxxxx>
> ---
> drivers/soc/mediatek/mtk-cmdq-helper.c | 125 ++++++++++++++++-------
> include/linux/mailbox/mtk-cmdq-mailbox.h | 2 +
> include/linux/soc/mediatek/mtk-cmdq.h | 14 +--
> 3 files changed, 99 insertions(+), 42 deletions(-)
>
> diff --git a/drivers/soc/mediatek/mtk-cmdq-helper.c b/drivers/soc/mediatek/mtk-cmdq-helper.c
> index ff9fef5a032b..d3873ab21db3 100644
> --- a/drivers/soc/mediatek/mtk-cmdq-helper.c
> +++ b/drivers/soc/mediatek/mtk-cmdq-helper.c
> @@ -9,11 +9,43 @@
> #include <linux/mailbox_controller.h>
> #include <linux/soc/mediatek/mtk-cmdq.h>
>
> -#define CMDQ_ARG_A_WRITE_MASK 0xffff
> +#define CMDQ_GET_ARG_B(arg) (((arg) & GENMASK(31, 16)) >> 16)
> +#define CMDQ_GET_ARG_C(arg) ((arg) & GENMASK(15, 0))
> #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)
> +#define CMDQ_IMMEDIATE_VALUE 0
> +#define CMDQ_REG_TYPE 1
> +
> +struct cmdq_instruction {
> + s16 arg_c:16;
> + s16 arg_b:16;
> + s16 arg_a:16;
> + u8 s_op:5;
> + u8 arg_c_type:1;
> + u8 arg_b_type:1;
> + u8 arg_a_type:1;
> + u8 op:8;
> +};
> +
> +static void cmdq_pkt_instr_encoder(struct cmdq_pkt *pkt, s16 arg_c, s16 arg_b,
> + s16 arg_a, u8 s_op, u8 arg_c_type,
> + u8 arg_b_type, u8 arg_a_type, u8 op)
> +{
> + struct cmdq_instruction *cmdq_inst;
> +
> + cmdq_inst = pkt->va_base + pkt->cmd_buf_size;
> + cmdq_inst->op = op;
> + cmdq_inst->arg_a_type = arg_a_type;
> + cmdq_inst->arg_b_type = arg_b_type;
> + cmdq_inst->arg_c_type = arg_c_type;
> + cmdq_inst->s_op = s_op;
> + cmdq_inst->arg_a = arg_a;
> + cmdq_inst->arg_b = arg_b;
> + cmdq_inst->arg_c = arg_c;
> + pkt->cmd_buf_size += CMDQ_INST_SIZE;
> +}
>
> static void cmdq_client_timeout(struct timer_list *t)
> {
> @@ -110,10 +142,11 @@ 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, s16 arg_c, s16 arg_b,
> + s16 arg_a, u8 s_op, u8 arg_c_type,
> + u8 arg_b_type, u8 arg_a_type,
> + enum cmdq_code code)
> {
> - u64 *cmd_ptr;
>
> if (unlikely(pkt->cmd_buf_size + CMDQ_INST_SIZE > pkt->buf_size)) {
> /*
> @@ -129,65 +162,72 @@ 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;
> - pkt->cmd_buf_size += CMDQ_INST_SIZE;
> + cmdq_pkt_instr_encoder(pkt, arg_c, arg_b, arg_a, s_op, arg_c_type,
> + arg_b_type, arg_a_type, code);
>
> return 0;
> }
>
> -int cmdq_pkt_write(struct cmdq_pkt *pkt, u32 value, u32 subsys, u32 offset)
> +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);
> -
> - return cmdq_pkt_append_command(pkt, CMDQ_CODE_WRITE, arg_a, value);
> + return cmdq_pkt_append_command(pkt, CMDQ_GET_ARG_C(value),
> + CMDQ_GET_ARG_B(value), offset, subsys,
> + CMDQ_IMMEDIATE_VALUE,
> + CMDQ_IMMEDIATE_VALUE,
> + CMDQ_IMMEDIATE_VALUE, CMDQ_CODE_WRITE);

I do not understand why you invent a encoder function. It neither reduce
the code size, nor make code easier for reading. If for easier reading,
I suggest this way:

struct cmdq_instruction {
union {
struct {
u32 value;
u16 offset;
u8 subsys;
};

struct {
...
};
};
u8 op;
};

struct cmdq_instruction *inst;

inst = cmdq_pkt_append_command(pkt);
if (!inst)
return -ENOMEM;

inst->op = CMDQ_CODE_WRITE;
inst->subsys = subsys;
inst->offset = offset;
inst->value = value;

Regards,
CK

> }
> EXPORT_SYMBOL(cmdq_pkt_write);
>
> -int cmdq_pkt_write_mask(struct cmdq_pkt *pkt, u32 value,
> - u32 subsys, u32 offset, u32 mask)
> +int cmdq_pkt_write_mask(struct cmdq_pkt *pkt, u8 subsys, u16 offset,
> + u32 value, u32 mask)
> {
> u32 offset_mask = offset;
> int err = 0;
>
> if (mask != 0xffffffff) {
> - err = cmdq_pkt_append_command(pkt, CMDQ_CODE_MASK, 0, ~mask);
> + err = cmdq_pkt_append_command(pkt, CMDQ_GET_ARG_C(~mask),
> + CMDQ_GET_ARG_B(~mask),
> + CMDQ_IMMEDIATE_VALUE,
> + CMDQ_IMMEDIATE_VALUE,
> + CMDQ_IMMEDIATE_VALUE,
> + CMDQ_IMMEDIATE_VALUE,
> + CMDQ_IMMEDIATE_VALUE,
> + CMDQ_CODE_MASK);
> 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;
> }
> EXPORT_SYMBOL(cmdq_pkt_write_mask);
>
> -int cmdq_pkt_wfe(struct cmdq_pkt *pkt, u32 event)
> +int cmdq_pkt_wfe(struct cmdq_pkt *pkt, u16 event)
> {
> - u32 arg_b;
> -
> 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;
> -
> - return cmdq_pkt_append_command(pkt, CMDQ_CODE_WFE, event, arg_b);
> + return cmdq_pkt_append_command(pkt, CMDQ_GET_ARG_C(CMDQ_WFE_OPTION),
> + CMDQ_GET_ARG_B(CMDQ_WFE_OPTION), event,
> + CMDQ_IMMEDIATE_VALUE,
> + CMDQ_IMMEDIATE_VALUE,
> + CMDQ_IMMEDIATE_VALUE,
> + CMDQ_IMMEDIATE_VALUE,
> + CMDQ_CODE_WFE);
> }
> EXPORT_SYMBOL(cmdq_pkt_wfe);
>
> -int cmdq_pkt_clear_event(struct cmdq_pkt *pkt, u32 event)
> +int cmdq_pkt_clear_event(struct cmdq_pkt *pkt, u16 event)
> {
> if (event >= CMDQ_MAX_EVENT)
> return -EINVAL;
>
> - return cmdq_pkt_append_command(pkt, CMDQ_CODE_WFE, event,
> - CMDQ_WFE_UPDATE);
> + return cmdq_pkt_append_command(pkt, CMDQ_GET_ARG_C(CMDQ_WFE_UPDATE),
> + CMDQ_GET_ARG_B(CMDQ_WFE_UPDATE), event,
> + CMDQ_IMMEDIATE_VALUE,
> + CMDQ_IMMEDIATE_VALUE,
> + CMDQ_IMMEDIATE_VALUE,
> + CMDQ_IMMEDIATE_VALUE,
> + CMDQ_CODE_WFE);
> }
> EXPORT_SYMBOL(cmdq_pkt_clear_event);
>
> @@ -196,10 +236,25 @@ static int cmdq_pkt_finalize(struct cmdq_pkt *pkt)
> int err;
>
> /* insert EOC and generate IRQ for each command iteration */
> - err = cmdq_pkt_append_command(pkt, CMDQ_CODE_EOC, 0, CMDQ_EOC_IRQ_EN);
> -
> + err = cmdq_pkt_append_command(pkt, CMDQ_GET_ARG_C(CMDQ_EOC_IRQ_EN),
> + CMDQ_GET_ARG_B(CMDQ_EOC_IRQ_EN),
> + CMDQ_IMMEDIATE_VALUE,
> + CMDQ_IMMEDIATE_VALUE,
> + CMDQ_IMMEDIATE_VALUE,
> + CMDQ_IMMEDIATE_VALUE,
> + CMDQ_IMMEDIATE_VALUE,
> + CMDQ_CODE_EOC);
> + if (err < 0)
> + return err;
> /* JUMP to end */
> - err |= cmdq_pkt_append_command(pkt, CMDQ_CODE_JUMP, 0, CMDQ_JUMP_PASS);
> + err = cmdq_pkt_append_command(pkt, CMDQ_GET_ARG_C(CMDQ_JUMP_PASS),
> + CMDQ_GET_ARG_B(CMDQ_JUMP_PASS),
> + CMDQ_IMMEDIATE_VALUE,
> + CMDQ_IMMEDIATE_VALUE,
> + CMDQ_IMMEDIATE_VALUE,
> + CMDQ_IMMEDIATE_VALUE,
> + CMDQ_IMMEDIATE_VALUE,
> + CMDQ_CODE_JUMP);
>
> return err;
> }
> diff --git a/include/linux/mailbox/mtk-cmdq-mailbox.h b/include/linux/mailbox/mtk-cmdq-mailbox.h
> index 911475da7a53..f21801d32a3a 100644
> --- a/include/linux/mailbox/mtk-cmdq-mailbox.h
> +++ b/include/linux/mailbox/mtk-cmdq-mailbox.h
> @@ -19,6 +19,8 @@
> #define CMDQ_WFE_UPDATE BIT(31)
> #define CMDQ_WFE_WAIT BIT(15)
> #define CMDQ_WFE_WAIT_VALUE 0x1
> +#define CMDQ_WFE_OPTION (CMDQ_WFE_UPDATE | CMDQ_WFE_WAIT | \
> + CMDQ_WFE_WAIT_VALUE)
> /** cmdq event maximum */
> #define CMDQ_MAX_EVENT 0x3ff
>
> diff --git a/include/linux/soc/mediatek/mtk-cmdq.h b/include/linux/soc/mediatek/mtk-cmdq.h
> index 4e8899972db4..52f69c8db8de 100644
> --- a/include/linux/soc/mediatek/mtk-cmdq.h
> +++ b/include/linux/soc/mediatek/mtk-cmdq.h
> @@ -60,26 +60,26 @@ void cmdq_pkt_destroy(struct cmdq_pkt *pkt);
> /**
> * cmdq_pkt_write() - append write command to the CMDQ packet
> * @pkt: the CMDQ packet
> - * @value: the specified target register value
> * @subsys: the CMDQ sub system code
> * @offset: register offset from CMDQ sub system
> + * @value: the specified target register value
> *
> * Return: 0 for success; else the error code is returned
> */
> -int cmdq_pkt_write(struct cmdq_pkt *pkt, u32 value, u32 subsys, u32 offset);
> +int cmdq_pkt_write(struct cmdq_pkt *pkt, u8 subsys, u16 offset, u32 value);
>
> /**
> * cmdq_pkt_write_mask() - append write command with mask to the CMDQ packet
> * @pkt: the CMDQ packet
> - * @value: the specified target register value
> * @subsys: the CMDQ sub system code
> * @offset: register offset from CMDQ sub system
> + * @value: the specified target register value
> * @mask: the specified target register mask
> *
> * Return: 0 for success; else the error code is returned
> */
> -int cmdq_pkt_write_mask(struct cmdq_pkt *pkt, u32 value,
> - u32 subsys, u32 offset, u32 mask);
> +int cmdq_pkt_write_mask(struct cmdq_pkt *pkt, u8 subsys, u16 offset,
> + u32 value, u32 mask);
>
> /**
> * cmdq_pkt_wfe() - append wait for event command to the CMDQ packet
> @@ -88,7 +88,7 @@ int cmdq_pkt_write_mask(struct cmdq_pkt *pkt, u32 value,
> *
> * Return: 0 for success; else the error code is returned
> */
> -int cmdq_pkt_wfe(struct cmdq_pkt *pkt, u32 event);
> +int cmdq_pkt_wfe(struct cmdq_pkt *pkt, u16 event);
>
> /**
> * cmdq_pkt_clear_event() - append clear event command to the CMDQ packet
> @@ -97,7 +97,7 @@ int cmdq_pkt_wfe(struct cmdq_pkt *pkt, u32 event);
> *
> * Return: 0 for success; else the error code is returned
> */
> -int cmdq_pkt_clear_event(struct cmdq_pkt *pkt, u32 event);
> +int cmdq_pkt_clear_event(struct cmdq_pkt *pkt, u16 event);
>
> /**
> * cmdq_pkt_flush_async() - trigger CMDQ to asynchronously execute the CMDQ