#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)
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;
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,
cancel_delayed_work_sync(&hdcp_work[i].watchdog_timer_dwork);
}
+ kfree(hdcp_work->srm);
+ kfree(hdcp_work->srm_temp);
kfree(hdcp_work);
-
}
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);
}
+
+/* NOTE: From the usermodes prospective you only need to call write *ONCE*, the kernel
+ * will automatically call once or twice depending on the size
+ *
+ * call: "cat file > /sys/class/drm/card0/device/hdcp_srm" from usermode no matter what the size is
+ *
+ * The kernel can only send PAGE_SIZE at once and since MAX_SRM_FILE(5120) > PAGE_SIZE(4096),
+ * srm_data_write can be called multiple times.
+ *
+ * sysfs interface doesn't tell us the size we will get so we are sending partial SRMs to psp and on
+ * the last call we will send the full SRM. PSP will fail on every call before the last.
+ *
+ * This means we don't know if the SRM is good until the last call. And because of this limitation we
+ * cannot throw errors early as it will stop the kernel from writing to sysfs
+ *
+ * Example 1:
+ * Good SRM size = 5096
+ * first call to write 4096 -> PSP fails
+ * Second call to write 1000 -> PSP Pass -> SRM is set
+ *
+ * Example 2:
+ * Bad SRM size = 4096
+ * first call to write 4096 -> PSP fails (This is the same as above, but we don't know if this
+ * is the last call)
+ *
+ * Solution?:
+ * 1: Parse the SRM? -> It is signed so we don't know the EOF
+ * 2: We can have another sysfs that passes the size before calling set. -> simpler solution
+ * below
+ *
+ * Easy Solution:
+ * Always call get after Set to verify if set was successful.
+ * +----------------------+
+ * | Why it works: |
+ * +----------------------+
+ * PSP will only update its srm if its older than the one we are trying to load.
+ * Always do set first than get.
+ * -if we try to "1. SET" a older version PSP will reject it and we can "2. GET" the newer
+ * version and save it
+ *
+ * -if we try to "1. SET" a newer version PSP will accept it and we can "2. GET" the
+ * same(newer) version back and save it
+ *
+ * -if we try to "1. SET" a newer version and PSP rejects it. That means the format is
+ * incorrect/corrupted and we should correct our SRM by getting it from PSP
+ */
+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;
+}
+
+/* From the hdcp spec (5.Renewability) SRM needs to be stored in a non-volatile memory.
+ *
+ * For example,
+ * if Application "A" sets the SRM (ver 2) and we reboot/suspend and later when Application "B"
+ * needs to use HDCP, the version in PSP should be SRM(ver 2). So SRM should be persistent
+ * across boot/reboots/suspend/resume/shutdown
+ *
+ * Currently when the system goes down (suspend/shutdown) the SRM is cleared from PSP. For HDCP we need
+ * to make the SRM persistent.
+ *
+ * -PSP owns the checking of SRM but doesn't have the ability to store it in a non-volatile memory.
+ * -The kernel cannot write to the file systems.
+ * -So we need usermode to do this for us, which is why an interface for usermode is needed
+ *
+ *
+ *
+ * Usermode can read/write to/from PSP using the sysfs interface
+ * For example:
+ * to save SRM from PSP to storage : cat /sys/class/drm/card0/device/hdcp_srm > srmfile
+ * to load from storage to PSP: cat srmfile > /sys/class/drm/card0/device/hdcp_srm
+ */
+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)
{
int max_caps = dc->caps.max_links;
- struct hdcp_workqueue *hdcp_work = kzalloc(max_caps*sizeof(*hdcp_work), GFP_KERNEL);
+ struct hdcp_workqueue *hdcp_work;
int i = 0;
+ hdcp_work = kcalloc(max_caps, sizeof(*hdcp_work), GFP_KERNEL);
if (hdcp_work == NULL)
+ return NULL;
+
+ 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);
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->srm);
+ kfree(hdcp_work->srm_temp);
kfree(hdcp_work);
return NULL;
projects / linux-2.6-microblaze.git / blobdiff