Re: [PATCH v2 7/8] drm/i915: Keep the AKSV details in intel_dp_hdcp_write_an_aksv()

Ramalingam C
2018-02-23T11:16:37Z

This is really making it cleaner.

Reviewed-by: Ramalingam C <ramalingam.c@intel.com>

On Friday 23 February 2018 02:57 AM, Ville Syrjala wrote:
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
>
> Let's try to keep the details on the AKSV stuff concentrated
> in one place. So move the control bit and +5 data size handling
> there.
>
> v2: Increase txbuf[] to include the payload which intel_dp_aux_xfer()
> will still load into the registers even though the hardware
> will ignore it
>
> Cc: Sean Paul <seanpaul@chromium.org>
> Cc: Ramalingam C <ramalingam.c@intel.com>
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
> ---
> drivers/gpu/drm/i915/intel_dp.c | 42 +++++++++++++----------------------------
> 1 file changed, 13 insertions(+), 29 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
> index 217cc6aee477..0d699d230b77 100644
> --- a/drivers/gpu/drm/i915/intel_dp.c
> +++ b/drivers/gpu/drm/i915/intel_dp.c
> @@ -1059,29 +1059,11 @@ 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_xfer(struct intel_dp *intel_dp,
> const uint8_t *send, int send_bytes,
> - uint8_t *recv, int recv_size, bool aksv_write)
> + uint8_t *recv, int recv_size,
> + u32 aux_send_ctl_flags)
> {
> struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
> struct drm_i915_private *dev_priv =
> @@ -1145,11 +1127,12 @@ intel_dp_aux_xfer(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,
> - aksv_write);
> + u32 send_ctl = intel_dp->get_aux_send_ctl(intel_dp,
> + has_aux_irq,
> + send_bytes,
> + aux_clock_divider);
> +
> + send_ctl |= aux_send_ctl_flags;
>
> /* Must try at least 3 times according to DP spec */
> for (try = 0; try < 5; try++) {
> @@ -1287,7 +1270,7 @@ intel_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg)
> memcpy(txbuf + HEADER_SIZE, msg->buffer, msg->size);
>
> ret = intel_dp_aux_xfer(intel_dp, txbuf, txsize,
> - rxbuf, rxsize, false);
> + rxbuf, rxsize, 0);
> if (ret > 0) {
> msg->reply = rxbuf[0] >> 4;
>
> @@ -1310,7 +1293,7 @@ intel_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg)
> return -E2BIG;
>
> ret = intel_dp_aux_xfer(intel_dp, txbuf, txsize,
> - rxbuf, rxsize, false);
> + rxbuf, rxsize, 0);
> if (ret > 0) {
> msg->reply = rxbuf[0] >> 4;
> /*
> @@ -5085,7 +5068,7 @@ 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;
> + uint8_t txbuf[4+5] = {}, rxbuf[2], reply = 0;
You might want to use the macros for size of txbuf as  HEADER_SIZE +
DRM_HDCP_KSV_LEN, as it is done in the next patch.
--Ram
> ssize_t dpcd_ret;
> int ret;
>
> @@ -5110,7 +5093,8 @@ int intel_dp_hdcp_write_an_aksv(struct intel_digital_port *intel_dig_port,
> txbuf[3] = DRM_HDCP_KSV_LEN - 1;
>
> ret = intel_dp_aux_xfer(intel_dp, txbuf, sizeof(txbuf),
> - rxbuf, sizeof(rxbuf), true);
> + rxbuf, sizeof(rxbuf),
> + DP_AUX_CH_CTL_AUX_AKSV_SELECT);
> if (ret < 0) {
> DRM_ERROR("Write Aksv over DP/AUX failed (%d)\n", ret);
> return ret;