Re: [PATCH v6 14/16] ufs: mcq: Add completion support of a cqe

From: Manivannan Sadhasivam
Date: Tue Nov 29 2022 - 10:37:40 EST


On Mon, Nov 28, 2022 at 05:20:55PM -0800, Asutosh Das wrote:
> Add support for completing requests from Completion Queue.
> Some host controllers support vendor specific registers
> that provide a bitmap of all CQ's which have at least one
> completed CQE. Add this support.
> The MCQ specification doesn't provide the Task Tag or its
> equivalent in the Completion Queue Entry.
> So use an indirect method to find the Task Tag from the
> Completion Queue Entry.
>
> Co-developed-by: Can Guo <quic_cang@xxxxxxxxxxx>
> Signed-off-by: Can Guo <quic_cang@xxxxxxxxxxx>
> Signed-off-by: Asutosh Das <quic_asutoshd@xxxxxxxxxxx>

Reviewed-by: Manivannan Sadhasivam <mani@xxxxxxxxxx>

Thanks,
Mani

> Reviewed-by: Bart Van Assche <bvanassche@xxxxxxx>
> ---
> drivers/ufs/core/ufs-mcq.c | 61 ++++++++++++++++++++++++++++++++++++++++++
> drivers/ufs/core/ufshcd-priv.h | 43 +++++++++++++++++++++++++++++
> drivers/ufs/core/ufshcd.c | 37 +++++++++++++++++++++++++
> drivers/ufs/host/ufs-qcom.c | 14 ++++++++++
> drivers/ufs/host/ufs-qcom.h | 4 +++
> include/ufs/ufshcd.h | 7 +++++
> include/ufs/ufshci.h | 3 +++
> 7 files changed, 169 insertions(+)
>
> diff --git a/drivers/ufs/core/ufs-mcq.c b/drivers/ufs/core/ufs-mcq.c
> index 151caf3..68c4097 100644
> --- a/drivers/ufs/core/ufs-mcq.c
> +++ b/drivers/ufs/core/ufs-mcq.c
> @@ -25,6 +25,7 @@
> #define MCQ_CFG_MAC_MASK GENMASK(16, 8)
> #define MCQ_QCFG_SIZE 0x40
> #define MCQ_ENTRY_SIZE_IN_DWORD 8
> +#define CQE_UCD_BA GENMASK_ULL(63, 7)
>
> static int rw_queue_count_set(const char *val, const struct kernel_param *kp)
> {
> @@ -236,6 +237,63 @@ static void __iomem *mcq_opr_base(struct ufs_hba *hba,
> return opr->base + opr->stride * i;
> }
>
> +u32 ufshcd_mcq_read_cqis(struct ufs_hba *hba, int i)
> +{
> + return readl(mcq_opr_base(hba, OPR_CQIS, i) + REG_CQIS);
> +}
> +
> +void ufshcd_mcq_write_cqis(struct ufs_hba *hba, u32 val, int i)
> +{
> + writel(val, mcq_opr_base(hba, OPR_CQIS, i) + REG_CQIS);
> +}
> +
> +/*
> + * Current MCQ specification doesn't provide a Task Tag or its equivalent in
> + * the Completion Queue Entry. Find the Task Tag using an indirect method.
> + */
> +static int ufshcd_mcq_get_tag(struct ufs_hba *hba,
> + struct ufs_hw_queue *hwq,
> + struct cq_entry *cqe)
> +{
> + dma_addr_t dma_addr;
> +
> + /* sizeof(struct utp_transfer_cmd_desc) must be a multiple of 128 */
> + BUILD_BUG_ON(sizeof(struct utp_transfer_cmd_desc) & GENMASK(6, 0));
> +
> + /* Bits 63:7 UCD base address, 6:5 are reserved, 4:0 is SQ ID */
> + dma_addr = le64_to_cpu(cqe->command_desc_base_addr) & CQE_UCD_BA;
> +
> + return (dma_addr - hba->ucdl_dma_addr) /
> + sizeof(struct utp_transfer_cmd_desc);
> +}
> +
> +static void ufshcd_mcq_process_cqe(struct ufs_hba *hba,
> + struct ufs_hw_queue *hwq)
> +{
> + struct cq_entry *cqe = ufshcd_mcq_cur_cqe(hwq);
> + int tag = ufshcd_mcq_get_tag(hba, hwq, cqe);
> +
> + ufshcd_compl_one_cqe(hba, tag, cqe);
> +}
> +
> +unsigned long ufshcd_mcq_poll_cqe_nolock(struct ufs_hba *hba,
> + struct ufs_hw_queue *hwq)
> +{
> + unsigned long completed_reqs = 0;
> +
> + ufshcd_mcq_update_cq_tail_slot(hwq);
> + while (!ufshcd_mcq_is_cq_empty(hwq)) {
> + ufshcd_mcq_process_cqe(hba, hwq);
> + ufshcd_mcq_inc_cq_head_slot(hwq);
> + completed_reqs++;
> + }
> +
> + if (completed_reqs)
> + ufshcd_mcq_update_cq_head(hwq);
> +
> + return completed_reqs;
> +}
> +
> void ufshcd_mcq_make_queues_operational(struct ufs_hba *hba)
> {
> struct ufs_hw_queue *hwq;
> @@ -279,6 +337,9 @@ void ufshcd_mcq_make_queues_operational(struct ufs_hba *hba)
> hwq->mcq_cq_head = mcq_opr_base(hba, OPR_CQD, i) + REG_CQHP;
> hwq->mcq_cq_tail = mcq_opr_base(hba, OPR_CQD, i) + REG_CQTP;
>
> + /* Reinitializing is needed upon HC reset */
> + hwq->sq_tail_slot = hwq->cq_tail_slot = hwq->cq_head_slot = 0;
> +
> /* Enable Tail Entry Push Status interrupt only for non-poll queues */
> if (i < hba->nr_hw_queues - hba->nr_queues[HCTX_TYPE_POLL])
> writel(1, mcq_opr_base(hba, OPR_CQIS, i) + REG_CQIE);
> diff --git a/drivers/ufs/core/ufshcd-priv.h b/drivers/ufs/core/ufshcd-priv.h
> index 2a7fb60..4dcb7f9 100644
> --- a/drivers/ufs/core/ufshcd-priv.h
> +++ b/drivers/ufs/core/ufshcd-priv.h
> @@ -69,6 +69,10 @@ int ufshcd_mcq_memory_alloc(struct ufs_hba *hba);
> void ufshcd_mcq_make_queues_operational(struct ufs_hba *hba);
> void ufshcd_mcq_config_mac(struct ufs_hba *hba, u32 max_active_cmds);
> void ufshcd_mcq_select_mcq_mode(struct ufs_hba *hba);
> +u32 ufshcd_mcq_read_cqis(struct ufs_hba *hba, int i);
> +void ufshcd_mcq_write_cqis(struct ufs_hba *hba, u32 val, int i);
> +unsigned long ufshcd_mcq_poll_cqe_nolock(struct ufs_hba *hba,
> + struct ufs_hw_queue *hwq);
> struct ufs_hw_queue *ufshcd_mcq_req_to_hwq(struct ufs_hba *hba,
> struct request *req);
>
> @@ -261,6 +265,15 @@ static inline int ufshcd_mcq_vops_op_runtime_config(struct ufs_hba *hba)
> return -EOPNOTSUPP;
> }
>
> +static inline int ufshcd_vops_get_outstanding_cqs(struct ufs_hba *hba,
> + unsigned long *ocqs)
> +{
> + if (hba->vops && hba->vops->get_outstanding_cqs)
> + return hba->vops->get_outstanding_cqs(hba, ocqs);
> +
> + return -EOPNOTSUPP;
> +}
> +
> extern const struct ufs_pm_lvl_states ufs_pm_lvl_states[];
>
> /**
> @@ -347,4 +360,34 @@ static inline void ufshcd_inc_sq_tail(struct ufs_hw_queue *q)
> writel(val, q->mcq_sq_tail);
> }
>
> +static inline void ufshcd_mcq_update_cq_tail_slot(struct ufs_hw_queue *q)
> +{
> + u32 val = readl(q->mcq_cq_tail);
> +
> + q->cq_tail_slot = val / sizeof(struct cq_entry);
> +}
> +
> +static inline bool ufshcd_mcq_is_cq_empty(struct ufs_hw_queue *q)
> +{
> + return q->cq_head_slot == q->cq_tail_slot;
> +}
> +
> +static inline void ufshcd_mcq_inc_cq_head_slot(struct ufs_hw_queue *q)
> +{
> + q->cq_head_slot++;
> + if (q->cq_head_slot == q->max_entries)
> + q->cq_head_slot = 0;
> +}
> +
> +static inline void ufshcd_mcq_update_cq_head(struct ufs_hw_queue *q)
> +{
> + writel(q->cq_head_slot * sizeof(struct cq_entry), q->mcq_cq_head);
> +}
> +
> +static inline struct cq_entry *ufshcd_mcq_cur_cqe(struct ufs_hw_queue *q)
> +{
> + struct cq_entry *cqe = q->cqe_base_addr;
> +
> + return cqe + q->cq_head_slot;
> +}
> #endif /* _UFSHCD_PRIV_H_ */
> diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
> index 0024586..8d743c3 100644
> --- a/drivers/ufs/core/ufshcd.c
> +++ b/drivers/ufs/core/ufshcd.c
> @@ -6698,6 +6698,40 @@ static irqreturn_t ufshcd_tmc_handler(struct ufs_hba *hba)
> }
>
> /**
> + * ufshcd_handle_mcq_cq_events - handle MCQ completion queue events
> + * @hba: per adapter instance
> + *
> + * Returns IRQ_HANDLED if interrupt is handled
> + */
> +static irqreturn_t ufshcd_handle_mcq_cq_events(struct ufs_hba *hba)
> +{
> + struct ufs_hw_queue *hwq;
> + unsigned long outstanding_cqs;
> + unsigned int nr_queues;
> + int i, ret;
> + u32 events;
> +
> + ret = ufshcd_vops_get_outstanding_cqs(hba, &outstanding_cqs);
> + if (ret)
> + outstanding_cqs = (1U << hba->nr_hw_queues) - 1;
> +
> + /* Exclude the poll queues */
> + nr_queues = hba->nr_hw_queues - hba->nr_queues[HCTX_TYPE_POLL];
> + for_each_set_bit(i, &outstanding_cqs, nr_queues) {
> + hwq = &hba->uhq[i];
> +
> + events = ufshcd_mcq_read_cqis(hba, i);
> + if (events)
> + ufshcd_mcq_write_cqis(hba, events, i);
> +
> + if (events & UFSHCD_MCQ_CQIS_TAIL_ENT_PUSH_STS)
> + ufshcd_mcq_poll_cqe_nolock(hba, hwq);
> + }
> +
> + return IRQ_HANDLED;
> +}
> +
> +/**
> * ufshcd_sl_intr - Interrupt service routine
> * @hba: per adapter instance
> * @intr_status: contains interrupts generated by the controller
> @@ -6722,6 +6756,9 @@ static irqreturn_t ufshcd_sl_intr(struct ufs_hba *hba, u32 intr_status)
> if (intr_status & UTP_TRANSFER_REQ_COMPL)
> retval |= ufshcd_transfer_req_compl(hba);
>
> + if (intr_status & MCQ_CQ_EVENT_STATUS)
> + retval |= ufshcd_handle_mcq_cq_events(hba);
> +
> return retval;
> }
>
> diff --git a/drivers/ufs/host/ufs-qcom.c b/drivers/ufs/host/ufs-qcom.c
> index 77bdec3..96a58b4 100644
> --- a/drivers/ufs/host/ufs-qcom.c
> +++ b/drivers/ufs/host/ufs-qcom.c
> @@ -1555,6 +1555,19 @@ static int ufs_qcom_get_hba_mac(struct ufs_hba *hba)
> return MAX_SUPP_MAC;
> }
>
> +static int ufs_qcom_get_outstanding_cqs(struct ufs_hba *hba,
> + unsigned long *ocqs)
> +{
> + struct ufshcd_res_info *mcq_vs_res = &hba->res[RES_MCQ_VS];
> +
> + if (!mcq_vs_res->base)
> + return -EINVAL;
> +
> + *ocqs = readl(mcq_vs_res->base + UFS_MEM_CQIS_VS);
> +
> + return 0;
> +}
> +
> /*
> * struct ufs_hba_qcom_vops - UFS QCOM specific variant operations
> *
> @@ -1581,6 +1594,7 @@ static const struct ufs_hba_variant_ops ufs_hba_qcom_vops = {
> .mcq_config_resource = ufs_qcom_mcq_config_resource,
> .get_hba_mac = ufs_qcom_get_hba_mac,
> .op_runtime_config = ufs_qcom_op_runtime_config,
> + .get_outstanding_cqs = ufs_qcom_get_outstanding_cqs,
> };
>
> /**
> diff --git a/drivers/ufs/host/ufs-qcom.h b/drivers/ufs/host/ufs-qcom.h
> index f86e532..6912bdf 100644
> --- a/drivers/ufs/host/ufs-qcom.h
> +++ b/drivers/ufs/host/ufs-qcom.h
> @@ -73,6 +73,10 @@ enum {
> UFS_UFS_DBG_RD_EDTL_RAM = 0x1900,
> };
>
> +enum {
> + UFS_MEM_CQIS_VS = 0x8,
> +};
> +
> #define UFS_CNTLR_2_x_x_VEN_REGS_OFFSET(x) (0x000 + x)
> #define UFS_CNTLR_3_x_x_VEN_REGS_OFFSET(x) (0x400 + x)
>
> diff --git a/include/ufs/ufshcd.h b/include/ufs/ufshcd.h
> index ae20697..8441c46 100644
> --- a/include/ufs/ufshcd.h
> +++ b/include/ufs/ufshcd.h
> @@ -301,6 +301,7 @@ struct ufs_pwr_mode_info {
> * @mcq_config_resource: called to configure MCQ platform resources
> * @get_hba_mac: called to get vendor specific mac value, mandatory for mcq mode
> * @op_runtime_config: called to config Operation and runtime regs Pointers
> + * @get_outstanding_cqs: called to get outstanding completion queues
> */
> struct ufs_hba_variant_ops {
> const char *name;
> @@ -342,6 +343,8 @@ struct ufs_hba_variant_ops {
> int (*mcq_config_resource)(struct ufs_hba *hba);
> int (*get_hba_mac)(struct ufs_hba *hba);
> int (*op_runtime_config)(struct ufs_hba *hba);
> + int (*get_outstanding_cqs)(struct ufs_hba *hba,
> + unsigned long *ocqs);
> };
>
> /* clock gating state */
> @@ -1067,6 +1070,8 @@ struct ufs_hba {
> * @id: hardware queue ID
> * @sq_tp_slot: current slot to which SQ tail pointer is pointing
> * @sq_lock: serialize submission queue access
> + * @cq_tail_slot: current slot to which CQ tail pointer is pointing
> + * @cq_head_slot: current slot to which CQ head pointer is pointing
> */
> struct ufs_hw_queue {
> void __iomem *mcq_sq_head;
> @@ -1082,6 +1087,8 @@ struct ufs_hw_queue {
> u32 id;
> u32 sq_tail_slot;
> spinlock_t sq_lock;
> + u32 cq_tail_slot;
> + u32 cq_head_slot;
> };
>
> static inline bool is_mcq_enabled(struct ufs_hba *hba)
> diff --git a/include/ufs/ufshci.h b/include/ufs/ufshci.h
> index 8784b88..1df8425 100644
> --- a/include/ufs/ufshci.h
> +++ b/include/ufs/ufshci.h
> @@ -262,6 +262,9 @@ enum {
> /* UTMRLRSR - UTP Task Management Request Run-Stop Register 80h */
> #define UTP_TASK_REQ_LIST_RUN_STOP_BIT 0x1
>
> +/* CQISy - CQ y Interrupt Status Register */
> +#define UFSHCD_MCQ_CQIS_TAIL_ENT_PUSH_STS 0x1
> +
> /* UICCMD - UIC Command */
> #define COMMAND_OPCODE_MASK 0xFF
> #define GEN_SELECTOR_INDEX_MASK 0xFFFF
> --
> 2.7.4
>