[PATCH 3/5] drm/amd/display: Add sysfs interface for set/get srm
Bhawanpreet Lakha
Bhawanpreet.Lakha at amd.com
Thu Jan 16 20:29:43 UTC 2020
[Why]
We need to set/get SRM and linux kernel is not suppose to write to the
storage, so we need to provide a interface.
[How]
Provide interface so usermode can set/get srm
Signed-off-by: Bhawanpreet Lakha <Bhawanpreet.Lakha at amd.com>
Reviewed-by: Rodrigo Siqueira <Rodrigo.Siqueira at amd.com>
---
.../amd/display/amdgpu_dm/amdgpu_dm_hdcp.c | 124 +++++++++++++++++-
.../amd/display/amdgpu_dm/amdgpu_dm_hdcp.h | 6 +
2 files changed, 128 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.c
index a269916f7dd6..a191c84ad8eb 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.c
@@ -28,6 +28,8 @@
#include "amdgpu_dm.h"
#include "dm_helpers.h"
#include <drm/drm_hdcp.h>
+#include "hdcp_psp.h"
+
static bool
lp_write_i2c(void *handle, uint32_t address, const uint8_t *data, uint32_t size)
@@ -67,6 +69,16 @@ lp_read_dpcd(void *handle, uint32_t address, uint8_t *data, uint32_t size)
return dm_helpers_dp_read_dpcd(link->ctx, link, address, data, size);
}
+static uint8_t *psp_get_srm(struct psp_context *psp, uint32_t *srm_version, uint32_t *srm_size)
+{
+ return NULL;
+}
+
+static int psp_set_srm(struct psp_context *psp, uint8_t *srm, uint32_t srm_size, uint32_t *srm_version)
+{
+ return 0;
+}
+
static void process_output(struct hdcp_workqueue *hdcp_work)
{
struct mod_hdcp_output output = hdcp_work->output;
@@ -88,6 +100,18 @@ static void process_output(struct hdcp_workqueue *hdcp_work)
schedule_delayed_work(&hdcp_work->property_validate_dwork, msecs_to_jiffies(0));
}
+static void link_lock(struct hdcp_workqueue *work, bool lock)
+{
+
+ int i = 0;
+
+ for (i = 0; i < work->max_link; i++) {
+ if (lock)
+ mutex_lock(&work[i].mutex);
+ else
+ mutex_unlock(&work[i].mutex);
+ }
+}
void hdcp_update_display(struct hdcp_workqueue *hdcp_work,
unsigned int link_index,
struct amdgpu_dm_connector *aconnector,
@@ -302,7 +326,8 @@ void hdcp_destroy(struct hdcp_workqueue *hdcp_work)
}
kfree(hdcp_work);
-
+ kfree(hdcp_work->srm);
+ kfree(hdcp_work->srm_temp);
}
static void update_config(void *handle, struct cp_psp_stream_config *config)
@@ -338,6 +363,84 @@ static void update_config(void *handle, struct cp_psp_stream_config *config)
hdcp_update_display(hdcp_work, link_index, aconnector, DRM_MODE_HDCP_CONTENT_TYPE0, false);
}
+
+/*
+ * This can be called twice, because SRM_SIZE > PAGE_SIZE.
+ *
+ * We set the SRM on each call, if SRM_SIZE > PAGE_SIZE, PSP will fail on the
+ * first call but pass on the second call.
+ *
+ * Because of this we are not throwing any errors as it will stop the next call.
+ * So it is a good idea to call the "read" sysfs to verify that the SRM was set
+ *
+ */
+static ssize_t srm_data_write(struct file *filp, struct kobject *kobj, struct bin_attribute *bin_attr, char *buffer,
+ loff_t pos, size_t count)
+{
+ struct hdcp_workqueue *work;
+ uint32_t srm_version = 0;
+
+ work = container_of(bin_attr, struct hdcp_workqueue, attr);
+ link_lock(work, true);
+
+ memcpy(work->srm_temp + pos, buffer, count);
+
+ if (!psp_set_srm(work->hdcp.config.psp.handle, work->srm_temp, pos + count, &srm_version)) {
+ DRM_DEBUG_DRIVER("HDCP SRM SET version 0x%X", srm_version);
+ memcpy(work->srm, work->srm_temp, pos + count);
+ work->srm_size = pos + count;
+ work->srm_version = srm_version;
+ }
+
+
+ link_lock(work, false);
+
+ return count;
+}
+
+static ssize_t srm_data_read(struct file *filp, struct kobject *kobj, struct bin_attribute *bin_attr, char *buffer,
+ loff_t pos, size_t count)
+{
+ struct hdcp_workqueue *work;
+ uint8_t *srm = NULL;
+ uint32_t srm_version;
+ uint32_t srm_size;
+ size_t ret = count;
+
+ work = container_of(bin_attr, struct hdcp_workqueue, attr);
+
+ link_lock(work, true);
+
+ srm = psp_get_srm(work->hdcp.config.psp.handle, &srm_version, &srm_size);
+
+ if (!srm)
+ return -EINVAL;
+
+ if (pos >= srm_size)
+ ret = 0;
+
+ if (srm_size - pos < count) {
+ memcpy(buffer, srm + pos, srm_size - pos);
+ ret = srm_size - pos;
+ goto ret;
+ }
+
+ memcpy(buffer, srm + pos, count);
+
+ret:
+ link_lock(work, false);
+ return ret;
+}
+
+
+static const struct bin_attribute data_attr = {
+ .attr = {.name = "hdcp_srm", .mode = 0664},
+ .size = PSP_HDCP_SRM_FIRST_GEN_MAX_SIZE, /* Limit SRM size */
+ .write = srm_data_write,
+ .read = srm_data_read,
+};
+
+
struct hdcp_workqueue *hdcp_create_workqueue(struct amdgpu_device *adev, struct cp_psp *cp_psp, struct dc *dc)
{
@@ -348,10 +451,19 @@ struct hdcp_workqueue *hdcp_create_workqueue(struct amdgpu_device *adev, struct
if (hdcp_work == NULL)
goto fail_alloc_context;
+ hdcp_work->srm = kcalloc(PSP_HDCP_SRM_FIRST_GEN_MAX_SIZE, sizeof(*hdcp_work->srm), GFP_KERNEL);
+
+ if (hdcp_work->srm == NULL)
+ goto fail_alloc_context;
+
+ hdcp_work->srm_temp = kcalloc(PSP_HDCP_SRM_FIRST_GEN_MAX_SIZE, sizeof(*hdcp_work->srm_temp), GFP_KERNEL);
+
+ if (hdcp_work->srm_temp == NULL)
+ goto fail_alloc_context;
+
hdcp_work->max_link = max_caps;
for (i = 0; i < max_caps; i++) {
-
mutex_init(&hdcp_work[i].mutex);
INIT_WORK(&hdcp_work[i].cpirq_work, event_cpirq);
@@ -371,10 +483,18 @@ struct hdcp_workqueue *hdcp_create_workqueue(struct amdgpu_device *adev, struct
cp_psp->funcs.update_stream_config = update_config;
cp_psp->handle = hdcp_work;
+ /* File created at /sys/class/drm/card0/device/hdcp_srm*/
+ hdcp_work[0].attr = data_attr;
+
+ if (sysfs_create_bin_file(&adev->dev->kobj, &hdcp_work[0].attr))
+ DRM_WARN("Failed to create device file hdcp_srm");
+
return hdcp_work;
fail_alloc_context:
kfree(hdcp_work);
+ kfree(hdcp_work->srm);
+ kfree(hdcp_work->srm_temp);
return NULL;
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.h
index 331b50825510..5159b3a5e5b0 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.h
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.h
@@ -53,6 +53,12 @@ struct hdcp_workqueue {
enum mod_hdcp_encryption_status encryption_status;
uint8_t max_link;
+
+ uint8_t *srm;
+ uint8_t *srm_temp;
+ uint32_t srm_version;
+ uint32_t srm_size;
+ struct bin_attribute attr;
};
void hdcp_update_display(struct hdcp_workqueue *hdcp_work,
--
2.17.1
More information about the amd-gfx
mailing list