[RFC 01/14] drm/i915: allocate gem memory for mipi dbi cmd buffer

Gaurav K Singh
2015-05-29T10:39:53Z

Allocate gem memory for MIPI DBI command buffer. This memory
will be used when sending command via DBI interface.

Signed-off-by: Yogesh Mohan Marimuthu <yogesh.mohan.marimuthu@intel.com>
Signed-off-by: Gaurav K Singh <gaurav.k.singh@intel.com>
Signed-off-by: Shobhit Kumar <shobhit.kumar@intel.com>
---
drivers/gpu/drm/i915/intel_dsi.c | 31 +++++++++++++++++++++++++++++++
drivers/gpu/drm/i915/intel_dsi.h | 4 ++++
2 files changed, 35 insertions(+)

diff --git a/drivers/gpu/drm/i915/intel_dsi.c b/drivers/gpu/drm/i915/intel_dsi.c
index 5196642..2e3c801 100644
--- a/drivers/gpu/drm/i915/intel_dsi.c
+++ b/drivers/gpu/drm/i915/intel_dsi.c
@@ -415,6 +415,27 @@ static void intel_dsi_pre_enable(struct intel_encoder *encoder)

DRM_DEBUG_KMS("\n");

+ if (!intel_dsi->gem_obj && is_cmd_mode(intel_dsi)) {
+ intel_dsi->gem_obj = i915_gem_alloc_object(dev, 4096);
+ if (!intel_dsi->gem_obj) {
+ DRM_ERROR("Failed to allocate seqno page\n");
+ return;
+ }
+
+ i915_gem_object_set_cache_level(intel_dsi->gem_obj,
+ I915_CACHE_LLC);
+
+ if (i915_gem_obj_ggtt_pin(intel_dsi->gem_obj, 4096, 0)) {
+ DRM_ERROR("MIPI command buffer GTT pin failed");
+ return;
+ }
+
+ intel_dsi->cmd_buff =
+ kmap(sg_page(intel_dsi->gem_obj->pages->sgl));
+ intel_dsi->cmd_buff_phy_addr = page_to_phys(
+ sg_page(intel_dsi->gem_obj->pages->sgl));
+ }
+
/* Disable DPOunit clock gating, can stall pipe
* and we need DPLL REFA always enabled */
tmp = I915_READ(DPLL(pipe));
@@ -576,6 +597,12 @@ static void intel_dsi_post_disable(struct intel_encoder *encoder)

msleep(intel_dsi->panel_off_delay);
msleep(intel_dsi->panel_pwr_cycle_delay);
+
+ if (intel_dsi->gem_obj) {
+ kunmap(intel_dsi->cmd_buff);
+ i915_gem_object_ggtt_unpin(intel_dsi->gem_obj);
+ drm_gem_object_unreference(&intel_dsi->gem_obj->base);
+ }
}

static bool intel_dsi_get_hw_state(struct intel_encoder *encoder,
@@ -1048,6 +1075,10 @@ void intel_dsi_init(struct drm_device *dev)
intel_dsi->ports = (1 << PORT_C);
}

+ intel_dsi->cmd_buff = NULL;
+ intel_dsi->cmd_buff_phy_addr = 0;
+ intel_dsi->gem_obj = NULL;
+
/* Create a DSI host (and a device) for each port. */
for_each_dsi_port(port, intel_dsi->ports) {
struct intel_dsi_host *host;
diff --git a/drivers/gpu/drm/i915/intel_dsi.h b/drivers/gpu/drm/i915/intel_dsi.h
index 2784ac4..36ca3cc 100644
--- a/drivers/gpu/drm/i915/intel_dsi.h
+++ b/drivers/gpu/drm/i915/intel_dsi.h
@@ -44,6 +44,10 @@ struct intel_dsi {

struct intel_connector *attached_connector;

+ struct drm_i915_gem_object *gem_obj;
+ void *cmd_buff;
+ dma_addr_t cmd_buff_phy_addr;
+
/* bit mask of ports being driven */
u16 ports;

--
1.7.9.5