From: "Raju P.L.S.S.S.N" <rpls...@codeaurora.org>

tcs->lock was introduced to serialize access with in TCS group. But
even without tcs->lock, drv->lock is serving the same purpose. So
use a single drv->lock.

Other optimizations include -
 - Remove locking around clear_bit() in IRQ handler. clear_bit() is
   atomic.
 - Remove redundant read of TCS registers.
 - Use spin_lock instead of _irq variants as the locks are not held
   in interrupt context.

Fixes: 658628 ("drivers: qcom: rpmh-rsc: add RPMH controller for QCOM
SoCs")
Signed-off-by: Raju P.L.S.S.S.N <rpls...@codeaurora.org>
Signed-off-by: Lina Iyer <il...@codeaurora.org>
---
 drivers/soc/qcom/rpmh-internal.h |  2 --
 drivers/soc/qcom/rpmh-rsc.c      | 37 +++++++++++---------------------
 drivers/soc/qcom/rpmh.c          | 20 +++++++----------
 3 files changed, 21 insertions(+), 38 deletions(-)

diff --git a/drivers/soc/qcom/rpmh-internal.h b/drivers/soc/qcom/rpmh-internal.h
index a7bbbb67991c..969d5030860e 100644
--- a/drivers/soc/qcom/rpmh-internal.h
+++ b/drivers/soc/qcom/rpmh-internal.h
@@ -28,7 +28,6 @@ struct rsc_drv;
  * @offset:    start of the TCS group relative to the TCSes in the RSC
  * @num_tcs:   number of TCSes in this type
  * @ncpt:      number of commands in each TCS
- * @lock:      lock for synchronizing this TCS writes
  * @req:       requests that are sent from the TCS
  * @cmd_cache: flattened cache of cmds in sleep/wake TCS
  * @slots:     indicates which of @cmd_addr are occupied
@@ -40,7 +39,6 @@ struct tcs_group {
        u32 offset;
        int num_tcs;
        int ncpt;
-       spinlock_t lock;
        const struct tcs_request *req[MAX_TCS_PER_TYPE];
        u32 *cmd_cache;
        DECLARE_BITMAP(slots, MAX_TCS_SLOTS);
diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c
index e278fc11fe5c..92461311aef3 100644
--- a/drivers/soc/qcom/rpmh-rsc.c
+++ b/drivers/soc/qcom/rpmh-rsc.c
@@ -93,8 +93,7 @@ static void write_tcs_reg_sync(struct rsc_drv *drv, int reg, 
int tcs_id,
 
 static bool tcs_is_free(struct rsc_drv *drv, int tcs_id)
 {
-       return !test_bit(tcs_id, drv->tcs_in_use) &&
-              read_tcs_reg(drv, RSC_DRV_STATUS, tcs_id, 0);
+       return !test_bit(tcs_id, drv->tcs_in_use);
 }
 
 static struct tcs_group *get_tcs_of_type(struct rsc_drv *drv, int type)
@@ -104,29 +103,28 @@ static struct tcs_group *get_tcs_of_type(struct rsc_drv 
*drv, int type)
 
 static int tcs_invalidate(struct rsc_drv *drv, int type)
 {
-       int m;
+       int m, ret = 0;
        struct tcs_group *tcs;
 
        tcs = get_tcs_of_type(drv, type);
 
-       spin_lock(&tcs->lock);
-       if (bitmap_empty(tcs->slots, MAX_TCS_SLOTS)) {
-               spin_unlock(&tcs->lock);
-               return 0;
-       }
+       spin_lock(&drv->lock);
+       if (bitmap_empty(tcs->slots, MAX_TCS_SLOTS))
+               goto done;
 
        for (m = tcs->offset; m < tcs->offset + tcs->num_tcs; m++) {
                if (!tcs_is_free(drv, m)) {
-                       spin_unlock(&tcs->lock);
-                       return -EAGAIN;
+                       ret = -EAGAIN;
+                       goto done;
                }
                write_tcs_reg_sync(drv, RSC_DRV_CMD_ENABLE, m, 0);
                write_tcs_reg_sync(drv, RSC_DRV_CMD_WAIT_FOR_CMPL, m, 0);
        }
        bitmap_zero(tcs->slots, MAX_TCS_SLOTS);
-       spin_unlock(&tcs->lock);
 
-       return 0;
+done:
+       spin_unlock(&drv->lock);
+       return ret;
 }
 
 /**
@@ -242,9 +240,7 @@ static irqreturn_t tcs_tx_done(int irq, void *p)
                write_tcs_reg(drv, RSC_DRV_CMD_ENABLE, i, 0);
                write_tcs_reg(drv, RSC_DRV_CMD_WAIT_FOR_CMPL, i, 0);
                write_tcs_reg(drv, RSC_DRV_IRQ_CLEAR, 0, BIT(i));
-               spin_lock(&drv->lock);
                clear_bit(i, drv->tcs_in_use);
-               spin_unlock(&drv->lock);
                if (req)
                        rpmh_tx_done(req, err);
        }
@@ -349,14 +345,12 @@ static int tcs_write(struct rsc_drv *drv, const struct 
tcs_request *msg)
 {
        struct tcs_group *tcs;
        int tcs_id;
-       unsigned long flags;
        int ret;
 
        tcs = get_tcs_for_msg(drv, msg);
        if (IS_ERR(tcs))
                return PTR_ERR(tcs);
 
-       spin_lock_irqsave(&tcs->lock, flags);
        spin_lock(&drv->lock);
        /*
         * The h/w does not like if we send a request to the same address,
@@ -364,26 +358,23 @@ static int tcs_write(struct rsc_drv *drv, const struct 
tcs_request *msg)
         */
        ret = check_for_req_inflight(drv, tcs, msg);
        if (ret) {
-               spin_unlock(&drv->lock);
                goto done_write;
        }
 
        tcs_id = find_free_tcs(tcs);
        if (tcs_id < 0) {
                ret = tcs_id;
-               spin_unlock(&drv->lock);
                goto done_write;
        }
 
        tcs->req[tcs_id - tcs->offset] = msg;
        set_bit(tcs_id, drv->tcs_in_use);
-       spin_unlock(&drv->lock);
 
        __tcs_buffer_write(drv, tcs_id, 0, msg);
        __tcs_trigger(drv, tcs_id);
 
 done_write:
-       spin_unlock_irqrestore(&tcs->lock, flags);
+       spin_unlock(&drv->lock);
        return ret;
 }
 
@@ -481,19 +472,18 @@ static int tcs_ctrl_write(struct rsc_drv *drv, const 
struct tcs_request *msg)
 {
        struct tcs_group *tcs;
        int tcs_id = 0, cmd_id = 0;
-       unsigned long flags;
        int ret;
 
        tcs = get_tcs_for_msg(drv, msg);
        if (IS_ERR(tcs))
                return PTR_ERR(tcs);
 
-       spin_lock_irqsave(&tcs->lock, flags);
+       spin_lock(&drv->lock);
        /* find the TCS id and the command in the TCS to write to */
        ret = find_slots(tcs, msg, &tcs_id, &cmd_id);
        if (!ret)
                __tcs_buffer_write(drv, tcs_id, cmd_id, msg);
-       spin_unlock_irqrestore(&tcs->lock, flags);
+       spin_unlock(&drv->lock);
 
        return ret;
 }
@@ -584,7 +574,6 @@ static int rpmh_probe_tcs_config(struct platform_device 
*pdev,
                tcs->type = tcs_cfg[i].type;
                tcs->num_tcs = tcs_cfg[i].n;
                tcs->ncpt = ncpt;
-               spin_lock_init(&tcs->lock);
 
                if (!tcs->num_tcs || tcs->type == CONTROL_TCS)
                        continue;
diff --git a/drivers/soc/qcom/rpmh.c b/drivers/soc/qcom/rpmh.c
index 035091fd44b8..12f830610b94 100644
--- a/drivers/soc/qcom/rpmh.c
+++ b/drivers/soc/qcom/rpmh.c
@@ -118,9 +118,8 @@ static struct cache_req *cache_rpm_request(struct 
rpmh_ctrlr *ctrlr,
                                           struct tcs_cmd *cmd)
 {
        struct cache_req *req;
-       unsigned long flags;
 
-       spin_lock_irqsave(&ctrlr->cache_lock, flags);
+       spin_lock(&ctrlr->cache_lock);
        req = __find_req(ctrlr, cmd->addr);
        if (req)
                goto existing;
@@ -154,7 +153,7 @@ static struct cache_req *cache_rpm_request(struct 
rpmh_ctrlr *ctrlr,
 
        ctrlr->dirty = true;
 unlock:
-       spin_unlock_irqrestore(&ctrlr->cache_lock, flags);
+       spin_unlock(&ctrlr->cache_lock);
 
        return req;
 }
@@ -283,23 +282,21 @@ EXPORT_SYMBOL(rpmh_write);
 
 static void cache_batch(struct rpmh_ctrlr *ctrlr, struct batch_cache_req *req)
 {
-       unsigned long flags;
 
-       spin_lock_irqsave(&ctrlr->cache_lock, flags);
+       spin_lock(&ctrlr->cache_lock);
        list_add_tail(&req->list, &ctrlr->batch_cache);
-       spin_unlock_irqrestore(&ctrlr->cache_lock, flags);
+       spin_unlock(&ctrlr->cache_lock);
 }
 
 static int flush_batch(struct rpmh_ctrlr *ctrlr)
 {
        struct batch_cache_req *req;
        const struct rpmh_request *rpm_msg;
-       unsigned long flags;
        int ret = 0;
        int i;
 
        /* Send Sleep/Wake requests to the controller, expect no response */
-       spin_lock_irqsave(&ctrlr->cache_lock, flags);
+       spin_lock(&ctrlr->cache_lock);
        list_for_each_entry(req, &ctrlr->batch_cache, list) {
                for (i = 0; i < req->count; i++) {
                        rpm_msg = req->rpm_msgs + i;
@@ -309,7 +306,7 @@ static int flush_batch(struct rpmh_ctrlr *ctrlr)
                                break;
                }
        }
-       spin_unlock_irqrestore(&ctrlr->cache_lock, flags);
+       spin_unlock(&ctrlr->cache_lock);
 
        return ret;
 }
@@ -317,13 +314,12 @@ static int flush_batch(struct rpmh_ctrlr *ctrlr)
 static void invalidate_batch(struct rpmh_ctrlr *ctrlr)
 {
        struct batch_cache_req *req, *tmp;
-       unsigned long flags;
 
-       spin_lock_irqsave(&ctrlr->cache_lock, flags);
+       spin_lock(&ctrlr->cache_lock);
        list_for_each_entry_safe(req, tmp, &ctrlr->batch_cache, list)
                kfree(req);
        INIT_LIST_HEAD(&ctrlr->batch_cache);
-       spin_unlock_irqrestore(&ctrlr->cache_lock, flags);
+       spin_unlock(&ctrlr->cache_lock);
 }
 
 /**
-- 
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