The current method of saving and restoring the context could cause a
restore before saving, effectively "restoring" zero values to registers.
Add ctx_valid field to indicate if the saved context is valid and can be
restored.
Also restructure the code to save the ctx_loss_count in save_context(),
which makes more sense than the previous method of storing new
ctx_loss_count in dispc_need_ctx_restore.
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@xxxxxx>
---
drivers/video/omap2/dss/dispc.c | 97 +++++++++++++++-----------------------
1 files changed, 38 insertions(+), 59 deletions(-)
diff --git a/drivers/video/omap2/dss/dispc.c b/drivers/video/omap2/dss/dispc.c
index 2de7e92..eac768f 100644
--- a/drivers/video/omap2/dss/dispc.c
+++ b/drivers/video/omap2/dss/dispc.c
@@ -108,6 +108,7 @@ static struct {
u32 error_irqs;
struct work_struct error_work;
+ bool ctx_valid;
u32 ctx[DISPC_SZ_REGS / sizeof(u32)];
#ifdef CONFIG_OMAP2_DSS_COLLECT_IRQ_STATS
@@ -140,6 +141,23 @@ static inline u32 dispc_read_reg(const u16 idx)
return __raw_readl(dispc.base + idx);
}
+static int dispc_get_ctx_loss_count(void)
+{
+ struct device *dev = &dispc.pdev->dev;
+ struct omap_display_platform_data *pdata = dev->platform_data;
+ struct omap_dss_board_info *board_data = pdata->board_data;
+ int cnt;
+
+ if (!board_data->get_context_loss_count)
+ return -ENOENT;
+
+ cnt = board_data->get_context_loss_count(dev);
+
+ WARN_ONCE(cnt < 0, "get_context_loss_count failed: %d\n", cnt);
+
+ return cnt;
+}
+
#define SR(reg) \
dispc.ctx[DISPC_##reg / sizeof(u32)] = dispc_read_reg(DISPC_##reg)
#define RR(reg) \
@@ -316,14 +334,30 @@ static void dispc_save_context(void)
if (dss_has_feature(FEAT_CORE_CLK_DIV))
SR(DIVISOR);
+
+ dispc.ctx_loss_cnt = dispc_get_ctx_loss_count();
+ dispc.ctx_valid = true;
+
+ DSSDBG("context saved, ctx_loss_count %d\n", dispc.ctx_loss_cnt);
}
static void dispc_restore_context(void)
{
- int i;
+ int i, ctx;
DSSDBG("dispc_restore_context\n");
+ if (!dispc.ctx_valid)
+ return;
+
+ ctx = dispc_get_ctx_loss_count();
+
+ if (ctx >= 0 && ctx == dispc.ctx_loss_cnt)
+ return;
+
+ DSSDBG("ctx_loss_count: saved %d, current %d\n",
+ dispc.ctx_loss_cnt, ctx);
+
/*RR(IRQENABLE);*/
/*RR(CONTROL);*/
RR(CONFIG);
@@ -502,65 +536,13 @@ static void dispc_restore_context(void)
* the context is fully restored
*/
RR(IRQENABLE);
+
+ DSSDBG("context restored\n");
}
#undef SR
#undef RR
-static void dispc_init_ctx_loss_count(void)
-{
- struct device *dev = &dispc.pdev->dev;
- struct omap_display_platform_data *pdata = dev->platform_data;
- struct omap_dss_board_info *board_data = pdata->board_data;
- int cnt = 0;
-
- /*
- * get_context_loss_count returns negative on error. We'll ignore the
- * error and store the error to ctx_loss_cnt, which will cause
- * dispc_need_ctx_restore() call to return true.
- */
-
- if (board_data->get_context_loss_count)
- cnt = board_data->get_context_loss_count(dev);
-
- WARN_ON(cnt < 0);
-
- dispc.ctx_loss_cnt = cnt;
-
- DSSDBG("initial ctx_loss_cnt %u\n", cnt);
-}
-
-static bool dispc_need_ctx_restore(void)
-{
- struct device *dev = &dispc.pdev->dev;
- struct omap_display_platform_data *pdata = dev->platform_data;
- struct omap_dss_board_info *board_data = pdata->board_data;
- int cnt;
-
- /*
- * If get_context_loss_count is not available, assume that we need
- * context restore always.
- */
- if (!board_data->get_context_loss_count)
- return true;
-
- cnt = board_data->get_context_loss_count(dev);
- if (cnt < 0) {
- dev_err(dev, "getting context loss count failed, will force "
- "context restore\n");
- dispc.ctx_loss_cnt = cnt;
- return true;
- }
-
- if (cnt == dispc.ctx_loss_cnt)
- return false;
-
- DSSDBG("ctx_loss_cnt %d -> %d\n", dispc.ctx_loss_cnt, cnt);
- dispc.ctx_loss_cnt = cnt;
-
- return true;
-}
-
int dispc_runtime_get(void)
{
int r;
@@ -3641,8 +3623,6 @@ static int omap_dispchw_probe(struct platform_device *pdev)
goto err_irq;
}
- dispc_init_ctx_loss_count();
-
pm_runtime_enable(&pdev->dev);
r = dispc_runtime_get();
@@ -3701,8 +3681,7 @@ static int dispc_runtime_resume(struct device *dev)
return r;
clk_enable(dispc.dss_clk);
- if (dispc_need_ctx_restore())
- dispc_restore_context();
+ dispc_restore_context();
return 0;
}
--
1.7.4.1
--
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