Re: [PATCH v3 net-next 2/5] net: wwan: t7xx: Infrastructure for early port configuration

[Jesse Brandeburg <jesse.brandeburg@intel.com>]

On 1/6/2023 8:26 AM, m.chetan.kumar@linux.intel.com wrote:
> From: M Chetan Kumar <m.chetan.kumar@linux.intel.com>
> 
> To support cases such as FW update or Core dump, the t7xx
> device is capable of signaling the host that a special port
> needs to be created before the handshake phase.
> 
> This patch adds the infrastructure required to create the
> early ports which also requires a different configuration of
> CLDMA queues.

nit: use imperative voice in your commit messages: no "this patch".
instead:
"Add the infrastructure..."

> 
> Signed-off-by: Haijun Liu <haijun.liu@mediatek.com>
> Co-developed-by: Madhusmita Sahu <madhusmita.sahu@intel.com>
> Signed-off-by: Madhusmita Sahu <madhusmita.sahu@intel.com>
> Signed-off-by: Ricardo Martinez <ricardo.martinez@linux.intel.com>
> Signed-off-by: Devegowda Chandrashekar <chandrashekar.devegowda@intel.com>
> Signed-off-by: M Chetan Kumar <m.chetan.kumar@linux.intel.com>
> --
> v3:
>   * No Change.
> v2:
>   * Move recv_skb handler to cldma_queue.
>   * Drop cldma_queue_type.
>   * Restore prototype of t7xx_port_send_raw_skb().
>   * Remove PORT_CFG_ID_INVALID check in t7xx_port_proxy_set_cfg().
>   * Add space before */.
>   * Drop unnecessary logs.
>   * Use WARN_ON on early port.
>   * Use new MISC_DEV_STATUS_INVALID instead of MISC_DEV_STATUS.
>   * Use macros instead of const identifiers.
>   * Change ports member type from pointer to array type.
>   * Prefix LK_EVENT_XX with MISC prefix.
>   * Use t7xx prefix for device_stage enums.
>   * Correct log messages.
>   * Don’t override pkt_size for non-download port under dedicated Queue.
>   * Drop cldma_txq_rxq_ids.
>   * Use macro for txq/rxq index.
>   * Use warn_on for rxq_idx comparison.
>   * Drop t7xx_port_proxy_get_port_by_name().
>   * Replace fsm poll with read_poll_timeout().
>   * Use "\n" consistently across log message.
>   * Remove local var _dev prefixes in fsm_routine_start().
>   * Use max_t.

...


> diff --git a/drivers/net/wwan/t7xx/t7xx_reg.h b/drivers/net/wwan/t7xx/t7xx_reg.h
> index c41d7d094c08..44352cd02460 100644
> --- a/drivers/net/wwan/t7xx/t7xx_reg.h
> +++ b/drivers/net/wwan/t7xx/t7xx_reg.h
> @@ -102,10 +102,28 @@ enum t7xx_pm_resume_state {
>   };
>   
>   #define T7XX_PCIE_MISC_DEV_STATUS		0x0d1c
> -#define MISC_STAGE_MASK				GENMASK(2, 0)
> -#define MISC_RESET_TYPE_PLDR			BIT(26)
>   #define MISC_RESET_TYPE_FLDR			BIT(27)
> -#define LINUX_STAGE				4
> +#define MISC_RESET_TYPE_PLDR			BIT(26)
> +#define MISC_DEV_STATUS_MASK			GENMASK(15, 0)
> +#define MISC_DEV_STATUS_INVALID			GENMASK(15, 0)

I don't see any uses of this, even though it's mentioned in the commit 
message. The only reason I looked was because it was weird to have 
DEV_STATUS_MASK and STATUS_INVALID be the same values, is that correct?


> +#define MISC_LK_EVENT_MASK			GENMASK(11, 8)
> +
> +enum lk_event_id {
> +	LK_EVENT_NORMAL = 0,
> +	LK_EVENT_CREATE_PD_PORT = 1,
> +	LK_EVENT_CREATE_POST_DL_PORT = 2,
> +	LK_EVENT_RESET = 7,
> +};
> +
> +#define MISC_STAGE_MASK				GENMASK(2, 0)
> +
> +enum t7xx_device_stage {
> +	T7XX_DEV_STAGE_INIT = 0,
> +	T7XX_DEV_STAGE_BROM_PRE = 1,
> +	T7XX_DEV_STAGE_BROM_POST = 2,
> +	T7XX_DEV_STAGE_LK = 3,
> +	T7XX_DEV_STAGE_LINUX = 4,
> +};
>   
>   #define T7XX_PCIE_RESOURCE_STATUS		0x0d28
>   #define T7XX_PCIE_RESOURCE_STS_MSK		GENMASK(4, 0)
> diff --git a/drivers/net/wwan/t7xx/t7xx_state_monitor.c b/drivers/net/wwan/t7xx/t7xx_state_monitor.c
> index 80edb8e75a6a..76fb5d57d4d7 100644
> --- a/drivers/net/wwan/t7xx/t7xx_state_monitor.c
> +++ b/drivers/net/wwan/t7xx/t7xx_state_monitor.c
> @@ -206,6 +206,34 @@ static void fsm_routine_exception(struct t7xx_fsm_ctl *ctl, struct t7xx_fsm_comm
>   		fsm_finish_command(ctl, cmd, 0);
>   }
>   
> +static void t7xx_lk_stage_event_handling(struct t7xx_fsm_ctl *ctl, unsigned int status)
> +{
> +	struct t7xx_modem *md = ctl->md;
> +	struct cldma_ctrl *md_ctrl;
> +	enum lk_event_id lk_event;
> +	struct device *dev;
> +
> +	dev = &md->t7xx_dev->pdev->dev;
> +	lk_event = FIELD_GET(MISC_LK_EVENT_MASK, status);
> +	switch (lk_event) {
> +	case LK_EVENT_NORMAL:
> +	case LK_EVENT_RESET:
> +		break;
> +
> +	case LK_EVENT_CREATE_PD_PORT:
> +		md_ctrl = md->md_ctrl[CLDMA_ID_AP];
> +		t7xx_cldma_hif_hw_init(md_ctrl);
> +		t7xx_cldma_stop(md_ctrl);
> +		t7xx_cldma_switch_cfg(md_ctrl, CLDMA_DEDICATED_Q_CFG);
> +		t7xx_cldma_start(md_ctrl);
> +		break;
> +
> +	default:
> +		dev_err(dev, "Invalid LK event %d\n", lk_event);
> +		break;
> +	}
> +}
> +
>   static int fsm_stopped_handler(struct t7xx_fsm_ctl *ctl)
>   {
>   	ctl->curr_state = FSM_STATE_STOPPED;
> @@ -317,8 +345,9 @@ static int fsm_routine_starting(struct t7xx_fsm_ctl *ctl)
>   static void fsm_routine_start(struct t7xx_fsm_ctl *ctl, struct t7xx_fsm_command *cmd)
>   {
>   	struct t7xx_modem *md = ctl->md;
> -	u32 dev_status;
> -	int ret;
> +	struct device *dev;
> +	u32 status, stage;
> +	int ret = 0;
>   
>   	if (!md)
>   		return;
> @@ -329,23 +358,55 @@ static void fsm_routine_start(struct t7xx_fsm_ctl *ctl, struct t7xx_fsm_command
>   		return;
>   	}
>   
> +	dev = &md->t7xx_dev->pdev->dev;
>   	ctl->curr_state = FSM_STATE_PRE_START;
>   	t7xx_md_event_notify(md, FSM_PRE_START);
>   
> -	ret = read_poll_timeout(ioread32, dev_status,
> -				(dev_status & MISC_STAGE_MASK) == LINUX_STAGE, 20000, 2000000,
> -				false, IREG_BASE(md->t7xx_dev) + T7XX_PCIE_MISC_DEV_STATUS);
> +	ret = read_poll_timeout(ioread32, status,
> +				((status & MISC_STAGE_MASK) == T7XX_DEV_STAGE_LINUX) ||
> +				((status & MISC_STAGE_MASK) == T7XX_DEV_STAGE_LK), 100000,
> +				20000000, false, IREG_BASE(md->t7xx_dev) +
> +				T7XX_PCIE_MISC_DEV_STATUS);
> +
>   	if (ret) {
> -		struct device *dev = &md->t7xx_dev->pdev->dev;
> +		ret = -ETIMEDOUT;
> +		dev_err(dev, "read poll %d\n", ret);
> +		goto finish_command;
> +	}
>   
> -		fsm_finish_command(ctl, cmd, -ETIMEDOUT);
> -		dev_err(dev, "Invalid device status 0x%lx\n", dev_status & MISC_STAGE_MASK);
> -		return;
> +	if (status != ctl->prev_status) {
> +		stage = FIELD_GET(MISC_STAGE_MASK, status);

if stage is only used down here you can declare it locally. cppcheck has 
a check that will find these for you.

> +		switch (stage) {
> +		case T7XX_DEV_STAGE_INIT:
> +		case T7XX_DEV_STAGE_BROM_PRE:
> +		case T7XX_DEV_STAGE_BROM_POST:
> +			dev_info(dev, "BROM_STAGE Entered\n");
> +			ret = t7xx_fsm_append_cmd(ctl, FSM_CMD_START, 0);
> +			break;
> +
> +		case T7XX_DEV_STAGE_LK:
> +			dev_info(dev, "LK_STAGE Entered\n");
> +			t7xx_lk_stage_event_handling(ctl, status);
> +			break;
> +
> +		case T7XX_DEV_STAGE_LINUX:
> +			dev_info(dev, "LINUX_STAGE Entered\n");
> +			t7xx_cldma_hif_hw_init(md->md_ctrl[CLDMA_ID_AP]);
> +			t7xx_cldma_hif_hw_init(md->md_ctrl[CLDMA_ID_MD]);
> +			t7xx_mhccif_mask_clr(md->t7xx_dev, D2H_INT_PORT_ENUM |
> +					     D2H_INT_ASYNC_MD_HK | D2H_INT_ASYNC_AP_HK);
> +			t7xx_port_proxy_set_cfg(md, PORT_CFG_ID_NORMAL);
> +			ret = fsm_routine_starting(ctl);
> +			break;
> +
> +		default:
> +			break;
> +		}
> +		ctl->prev_status = status;
>   	}
>   
> -	t7xx_cldma_hif_hw_init(md->md_ctrl[CLDMA_ID_AP]);
> -	t7xx_cldma_hif_hw_init(md->md_ctrl[CLDMA_ID_MD]);
> -	fsm_finish_command(ctl, cmd, fsm_routine_starting(ctl));
> +finish_command:
> +	fsm_finish_command(ctl, cmd, ret);
>   }
>   
>   static int fsm_main_thread(void *data)
> @@ -516,6 +577,7 @@ void t7xx_fsm_reset(struct t7xx_modem *md)
>   	fsm_flush_event_cmd_qs(ctl);
>   	ctl->curr_state = FSM_STATE_STOPPED;
>   	ctl->exp_flg = false;
> +	ctl->prev_status = 0;
>   }
>   
>   int t7xx_fsm_init(struct t7xx_modem *md)
> diff --git a/drivers/net/wwan/t7xx/t7xx_state_monitor.h b/drivers/net/wwan/t7xx/t7xx_state_monitor.h
> index b6e76f3903c8..5e8012567ba1 100644
> --- a/drivers/net/wwan/t7xx/t7xx_state_monitor.h
> +++ b/drivers/net/wwan/t7xx/t7xx_state_monitor.h
> @@ -96,6 +96,7 @@ struct t7xx_fsm_ctl {
>   	bool			exp_flg;
>   	spinlock_t		notifier_lock;		/* Protects notifier list */
>   	struct list_head	notifier_list;
> +	u32                     prev_status;
>   };
>   
>   struct t7xx_fsm_event {