msm: mdss: protect mdp registers from race condition

During the pipe configuration process it was possible for multiple
thread contexts to read and write common register data, resulting in
a race condition. In order to prevent a race condition, we are now
protecting access to common registers are with reg_lock mutex.

Change-Id: I724e7870e856b3303448edbdf00f334ad38483f6
Signed-off-by: Terence Hampson <thampson@codeaurora.org>
This commit is contained in:
Terence Hampson 2015-07-28 16:59:46 -04:00 committed by David Keitel
parent dcf1c899c1
commit 35d2cedadb

View file

@ -275,6 +275,7 @@ static void mdss_mdp_pipe_nrt_vbif_setup(struct mdss_data_type *mdata,
if (pipe->type != MDSS_MDP_PIPE_TYPE_DMA)
return;
mutex_lock(&mdata->reg_lock);
nrt_vbif_client_sel = readl_relaxed(mdata->mdp_base +
MMSS_MDP_RT_NRT_VBIF_CLIENT_SEL);
if (mdss_mdp_is_nrt_vbif_client(mdata, pipe))
@ -283,6 +284,7 @@ static void mdss_mdp_pipe_nrt_vbif_setup(struct mdss_data_type *mdata,
nrt_vbif_client_sel &= ~BIT(pipe->num - MDSS_MDP_SSPP_DMA0);
writel_relaxed(nrt_vbif_client_sel,
mdata->mdp_base + MMSS_MDP_RT_NRT_VBIF_CLIENT_SEL);
mutex_unlock(&mdata->reg_lock);
return;
}
@ -906,6 +908,7 @@ static void mdss_mdp_qos_vbif_remapper_setup(struct mdss_data_type *mdata,
if (mdata->npriority_lvl == 0)
return;
mutex_lock(&mdata->reg_lock);
for (i = 0; i < mdata->npriority_lvl; i++) {
reg_val = MDSS_VBIF_READ(mdata, MDSS_VBIF_QOS_REMAP_BASE + i*4,
is_nrt_vbif);
@ -917,6 +920,7 @@ static void mdss_mdp_qos_vbif_remapper_setup(struct mdss_data_type *mdata,
MDSS_VBIF_WRITE(mdata, MDSS_VBIF_QOS_REMAP_BASE + i*4, reg_val,
is_nrt_vbif);
}
mutex_unlock(&mdata->reg_lock);
}
/**