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[18/43] imx-drm: ipu-v3: Add ipu_idmac_enable_watermark()

Message ID 1402178205-22697-19-git-send-email-steve_longerbeam@mentor.com (mailing list archive)
State New, archived
Headers show

Commit Message

Steve Longerbeam June 7, 2014, 9:56 p.m. UTC 
Adds the function ipu_idmac_enable_watermark(), which enables or disables
watermarking in the IDMAC channel. Enabling watermarking can increase a
channel's AXI bus arbitration priority.

Signed-off-by: Steve Longerbeam <steve_longerbeam@mentor.com>
---
 drivers/staging/imx-drm/ipu-v3/ipu-common.c |   25 +++++++++++++++++++++++++
 include/linux/platform_data/imx-ipu-v3.h    |    1 +
 2 files changed, 26 insertions(+)
diff mbox

Patch

diff --git a/drivers/staging/imx-drm/ipu-v3/ipu-common.c b/drivers/staging/imx-drm/ipu-v3/ipu-common.c
index 32a51d6..8c5b8d3 100644
--- a/drivers/staging/imx-drm/ipu-v3/ipu-common.c
+++ b/drivers/staging/imx-drm/ipu-v3/ipu-common.c
@@ -982,6 +982,31 @@  int ipu_idmac_disable_channel(struct ipuv3_channel *channel)
 }
 EXPORT_SYMBOL_GPL(ipu_idmac_disable_channel);
 
+/*
+ * The imx6 rev. D TRM says that enabling the WM feature will increase
+ * a channel's priority. Refer to Table 36-8 Calculated priority value.
+ * The sub-module that is the sink or source for the channel must enable
+ * watermark signal for this to take effect (SMFC_WM for instance).
+ */
+void ipu_idmac_enable_watermark(struct ipuv3_channel *channel, bool enable)
+{
+	struct ipu_soc *ipu = channel->ipu;
+	unsigned long flags;
+	u32 val;
+
+	spin_lock_irqsave(&ipu->lock, flags);
+
+	val = ipu_idmac_read(ipu, IDMAC_WM_EN(channel->num));
+	if (enable)
+		val |= 1 << (channel->num % 32);
+	else
+		val &= ~(1 << (channel->num % 32));
+	ipu_idmac_write(ipu, val, IDMAC_WM_EN(channel->num));
+
+	spin_unlock_irqrestore(&ipu->lock, flags);
+}
+EXPORT_SYMBOL_GPL(ipu_idmac_enable_watermark);
+
 static int ipu_memory_reset(struct ipu_soc *ipu)
 {
 	unsigned long timeout;
diff --git a/include/linux/platform_data/imx-ipu-v3.h b/include/linux/platform_data/imx-ipu-v3.h
index 681b9fd..d1def4d 100644
--- a/include/linux/platform_data/imx-ipu-v3.h
+++ b/include/linux/platform_data/imx-ipu-v3.h
@@ -202,6 +202,7 @@  void ipu_idmac_select_buffer(struct ipuv3_channel *channel, u32 buf_num);
 void ipu_idmac_clear_buffer(struct ipuv3_channel *channel, u32 buf_num);
 bool ipu_idmac_buffer_is_ready(struct ipuv3_channel *channel, u32 buf_num);
 int ipu_idmac_current_buffer(struct ipuv3_channel *channel);
+void ipu_idmac_enable_watermark(struct ipuv3_channel *channel, bool enable);
 
 /*
  * IPU Display Controller (dc) functions