This patch adds HDCP support for DisplayPort connectors by implementing the intel_hdcp_shim.
Most of this is straightforward read/write from/to DPCD registers. One thing worth pointing out is the Aksv output bit. It wasn't easily separable like it's HDMI counterpart, so it's crammed in with the rest of it.
Signed-off-by: Sean Paul seanpaul@chromium.org --- drivers/gpu/drm/i915/intel_dp.c | 243 ++++++++++++++++++++++++++++++++++++++-- 1 file changed, 236 insertions(+), 7 deletions(-)
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index d11281004109..091c8bcc4645 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -36,7 +36,9 @@ #include <drm/drm_atomic_helper.h> #include <drm/drm_crtc.h> #include <drm/drm_crtc_helper.h> +#include <drm/drm_dp_helper.h> #include <drm/drm_edid.h> +#include <drm/drm_hdcp.h> #include "intel_drv.h" #include <drm/i915_drm.h> #include "i915_drv.h" @@ -1039,10 +1041,29 @@ static uint32_t skl_get_aux_send_ctl(struct intel_dp *intel_dp, DP_AUX_CH_CTL_SYNC_PULSE_SKL(32); }
+static uint32_t intel_dp_get_aux_send_ctl(struct intel_dp *intel_dp, + bool has_aux_irq, + int send_bytes, + uint32_t aux_clock_divider, + bool aksv_write) +{ + uint32_t val = 0; + + if (aksv_write) { + send_bytes += 5; + val |= DP_AUX_CH_CTL_AUX_AKSV_SELECT; + } + + return val | intel_dp->get_aux_send_ctl(intel_dp, + has_aux_irq, + send_bytes, + aux_clock_divider); +} + static int intel_dp_aux_ch(struct intel_dp *intel_dp, const uint8_t *send, int send_bytes, - uint8_t *recv, int recv_size) + uint8_t *recv, int recv_size, bool aksv_write) { struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp); struct drm_i915_private *dev_priv = @@ -1102,10 +1123,11 @@ intel_dp_aux_ch(struct intel_dp *intel_dp, }
while ((aux_clock_divider = intel_dp->get_aux_clock_divider(intel_dp, clock++))) { - u32 send_ctl = intel_dp->get_aux_send_ctl(intel_dp, - has_aux_irq, - send_bytes, - aux_clock_divider); + u32 send_ctl = intel_dp_get_aux_send_ctl(intel_dp, + has_aux_irq, + send_bytes, + aux_clock_divider, + aksv_write);
/* Must try at least 3 times according to DP spec */ for (try = 0; try < 5; try++) { @@ -1242,7 +1264,8 @@ intel_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg) if (msg->buffer) memcpy(txbuf + HEADER_SIZE, msg->buffer, msg->size);
- ret = intel_dp_aux_ch(intel_dp, txbuf, txsize, rxbuf, rxsize); + ret = intel_dp_aux_ch(intel_dp, txbuf, txsize, rxbuf, rxsize, + false); if (ret > 0) { msg->reply = rxbuf[0] >> 4;
@@ -1264,7 +1287,8 @@ intel_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg) if (WARN_ON(rxsize > 20)) return -E2BIG;
- ret = intel_dp_aux_ch(intel_dp, txbuf, txsize, rxbuf, rxsize); + ret = intel_dp_aux_ch(intel_dp, txbuf, txsize, rxbuf, rxsize, + false); if (ret > 0) { msg->reply = rxbuf[0] >> 4; /* @@ -4310,6 +4334,8 @@ intel_dp_check_link_status(struct intel_dp *intel_dp)
intel_dp_retrain_link(intel_dp); } + + intel_hdcp_check_link(intel_dp->attached_connector); }
/* @@ -4977,6 +5003,203 @@ void intel_dp_encoder_suspend(struct intel_encoder *intel_encoder) pps_unlock(intel_dp); }
+static +int intel_dp_hdcp_write_an_aksv(struct intel_digital_port *intel_dig_port, + u8 *an) +{ + struct intel_dp *intel_dp = enc_to_intel_dp(&intel_dig_port->base.base); + uint8_t txbuf[4], rxbuf[2], reply = 0; + ssize_t dpcd_ret; + int ret; + + /* Output An first, that's easy */ + dpcd_ret = drm_dp_dpcd_write(&intel_dig_port->dp.aux, DP_AUX_HDCP_AN, + an, DRM_HDCP_AN_LEN); + if (dpcd_ret != DRM_HDCP_AN_LEN) { + DRM_ERROR("Failed to write An over DP/AUX (%ld)\n", dpcd_ret); + return dpcd_ret >= 0 ? -EIO : dpcd_ret; + } + + /* + * Since Aksv is Oh-So-Secret, we can't access it in software. So in + * order to get it on the wire, we need to create the AUX header as if + * we were writing the data, and then tickle the hardware to output the + * data once the header is sent out. + */ + txbuf[0] = (DP_AUX_NATIVE_WRITE << 4) | + ((DP_AUX_HDCP_AKSV >> 16) & 0xf); + txbuf[1] = (DP_AUX_HDCP_AKSV >> 8) & 0xff; + txbuf[2] = DP_AUX_HDCP_AKSV & 0xff; + txbuf[3] = DRM_HDCP_KSV_LEN - 1; + + ret = intel_dp_aux_ch(intel_dp, txbuf, sizeof(txbuf), rxbuf, + sizeof(rxbuf), true); + if (ret < 0) { + DRM_ERROR("Write Aksv over DP/AUX failed (%d)\n", ret); + return ret; + } else if (ret == 0) { + DRM_ERROR("Aksv write over DP/AUX was empty\n"); + return -EIO; + } + + reply = (rxbuf[0] >> 4) & DP_AUX_NATIVE_REPLY_MASK; + return reply == DP_AUX_NATIVE_REPLY_ACK ? 0 : -EIO; +} + +static int intel_dp_hdcp_read_bksv(struct intel_digital_port *intel_dig_port, + u8 *bksv) +{ + ssize_t ret; + ret = drm_dp_dpcd_read(&intel_dig_port->dp.aux, DP_AUX_HDCP_BKSV, bksv, + DRM_HDCP_KSV_LEN); + if (ret != DRM_HDCP_KSV_LEN) { + DRM_ERROR("Read Bksv from DP/AUX failed (%ld)\n", ret); + return ret >= 0 ? -EIO : ret; + } + return 0; +} + +static int intel_dp_hdcp_read_bstatus(struct intel_digital_port *intel_dig_port, + u8 *bstatus) +{ + ssize_t ret; + /* + * For some reason the HDMI and DP HDCP specs call this register + * definition by different names. In the HDMI spec, it's called BSTATUS, + * but in DP it's called BINFO. + */ + ret = drm_dp_dpcd_read(&intel_dig_port->dp.aux, DP_AUX_HDCP_BINFO, + bstatus, DRM_HDCP_BSTATUS_LEN); + if (ret != DRM_HDCP_BSTATUS_LEN) { + DRM_ERROR("Read bstatus from DP/AUX failed (%ld)\n", ret); + return ret >= 0 ? -EIO : ret; + } + return 0; +} + +static +int intel_dp_hdcp_repeater_present(struct intel_digital_port *intel_dig_port, + bool *repeater_present) +{ + ssize_t ret; + u8 bcaps; + ret = drm_dp_dpcd_read(&intel_dig_port->dp.aux, DP_AUX_HDCP_BCAPS, + &bcaps, 1); + if (ret != 1) { + DRM_ERROR("Read bcaps from DP/AUX failed (%ld)\n", ret); + return ret >= 0 ? -EIO : ret; + } + *repeater_present = bcaps & DP_BCAPS_REPEATER_PRESENT; + return 0; +} + +static +int intel_dp_hdcp_read_ri_prime(struct intel_digital_port *intel_dig_port, + u8 *ri_prime) +{ + ssize_t ret; + ret = drm_dp_dpcd_read(&intel_dig_port->dp.aux, DP_AUX_HDCP_RI_PRIME, + ri_prime, DRM_HDCP_RI_LEN); + if (ret != DRM_HDCP_RI_LEN) { + DRM_ERROR("Read Ri' from DP/AUX failed (%ld)\n", ret); + return ret >= 0 ? -EIO : ret; + } + return 0; +} + +static +int intel_dp_hdcp_read_ksv_ready(struct intel_digital_port *intel_dig_port, + bool *ksv_ready) +{ + ssize_t ret; + u8 bstatus; + ret = drm_dp_dpcd_read(&intel_dig_port->dp.aux, DP_AUX_HDCP_BSTATUS, + &bstatus, 1); + if (ret != 1) { + DRM_ERROR("Read bstatus from DP/AUX failed (%ld)\n", ret); + return ret >= 0 ? -EIO : ret; + } + *ksv_ready = bstatus & DP_BSTATUS_READY; + return 0; +} + +static +int intel_dp_hdcp_read_ksv_fifo(struct intel_digital_port *intel_dig_port, + int num_downstream, u8 *ksv_fifo) +{ + ssize_t ret; + int i; + + // KSV list is read via 15 byte window (3 entries @ 5 bytes each) + for (i = 0; i < num_downstream; i += 3) { + size_t len = min(num_downstream - i, 3) * DRM_HDCP_KSV_LEN; + ret = drm_dp_dpcd_read(&intel_dig_port->dp.aux, + DP_AUX_HDCP_KSV_FIFO, + ksv_fifo + i * DRM_HDCP_KSV_LEN, + len); + if (ret != len) { + DRM_ERROR("Read ksv[%d] from DP/AUX failed (%ld)\n", i, + ret); + return ret >= 0 ? -EIO : ret; + } + } + return 0; +} + +static +int intel_dp_hdcp_read_v_prime_part(struct intel_digital_port *intel_dig_port, + int i, u32 *part) +{ + ssize_t ret; + + if (i >= DRM_HDCP_V_PRIME_NUM_PARTS) + return -EINVAL; + + ret = drm_dp_dpcd_read(&intel_dig_port->dp.aux, + DP_AUX_HDCP_V_PRIME(i), part, + DRM_HDCP_V_PRIME_PART_LEN); + if (ret != DRM_HDCP_V_PRIME_PART_LEN) { + DRM_ERROR("Read v'[%d] from DP/AUX failed (%ld)\n", i, ret); + return ret >= 0 ? -EIO : ret; + } + return 0; +} + +static +int intel_dp_hdcp_toggle_signalling(struct intel_digital_port *intel_dig_port, + bool enable) +{ + /* Not used for single stream DisplayPort setups */ + return 0; +} + +static +bool intel_dp_hdcp_check_link(struct intel_digital_port *intel_dig_port) +{ + ssize_t ret; + u8 bstatus; + ret = drm_dp_dpcd_read(&intel_dig_port->dp.aux, DP_AUX_HDCP_BSTATUS, + &bstatus, 1); + if (ret != 1) { + DRM_ERROR("Read bstatus from DP/AUX failed (%ld)\n", ret); + return ret >= 0 ? -EIO : ret; + } + return !(bstatus & DP_BSTATUS_LINK_FAILURE); +} + +static const struct intel_hdcp_shim intel_dp_hdcp_shim = { + .write_an_aksv = intel_dp_hdcp_write_an_aksv, + .read_bksv = intel_dp_hdcp_read_bksv, + .read_bstatus = intel_dp_hdcp_read_bstatus, + .repeater_present = intel_dp_hdcp_repeater_present, + .read_ri_prime = intel_dp_hdcp_read_ri_prime, + .read_ksv_ready = intel_dp_hdcp_read_ksv_ready, + .read_ksv_fifo = intel_dp_hdcp_read_ksv_fifo, + .read_v_prime_part = intel_dp_hdcp_read_v_prime_part, + .toggle_signalling = intel_dp_hdcp_toggle_signalling, + .check_link = intel_dp_hdcp_check_link, +}; + static void intel_edp_panel_vdd_sanitize(struct intel_dp *intel_dp) { struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp); @@ -6097,6 +6320,12 @@ intel_dp_init_connector(struct intel_digital_port *intel_dig_port,
intel_dp_add_properties(intel_dp, connector);
+ if (INTEL_GEN(dev_priv) >= 9 && !intel_dp_is_edp(intel_dp)) { + drm_connector_attach_content_protection_property(connector); + intel_connector->hdcp_shim = &intel_dp_hdcp_shim; + INIT_DELAYED_WORK(&intel_connector->hdcp_work, intel_hdcp_work); + } + /* For G4X desktop chip, PEG_BAND_GAP_DATA 3:0 must first be written * 0xd. Failure to do so will result in spurious interrupts being * generated on the port when a cable is not attached.