Commit 55f083c3 authored by Ben Skeggs's avatar Ben Skeggs
Browse files

drm/nouveau/disp/dp: maintain link in response to hpd signal



This previously worked for the most part due to userspace doing a
modeset in response to HPD interrupts.  This will allow us to
properly handle cases where sync is lost for other reasons, or if
userspace isn't caring.
Signed-off-by: default avatarBen Skeggs <bskeggs@redhat.com>
parent 13a61757
......@@ -102,7 +102,7 @@ dp_set_link_config(struct dp_state *dp)
if (outp->dpcd[DPCD_RC02] & DPCD_RC02_ENHANCED_FRAME_CAP)
sink[1] |= DPCD_LC01_ENHANCED_FRAME_EN;
return nv_wraux(outp->base.edid, DPCD_LC00, sink, 2);
return nv_wraux(outp->base.edid, DPCD_LC00_LINK_BW_SET, sink, 2);
}
static void
......@@ -313,14 +313,16 @@ static const struct dp_rates {
{}
};
int
nouveau_dp_train(struct nvkm_output_dp *outp, u32 datarate)
void
nouveau_dp_train(struct work_struct *w)
{
struct nvkm_output_dp *outp = container_of(w, typeof(*outp), lt.work);
struct nouveau_disp *disp = nouveau_disp(outp);
const struct dp_rates *cfg = nouveau_dp_rates;
struct dp_state _dp = {
.outp = outp,
}, *dp = &_dp;
u32 datarate = 0;
int ret;
/* bring capabilities within encoder limits */
......@@ -342,6 +344,9 @@ nouveau_dp_train(struct nvkm_output_dp *outp, u32 datarate)
}
cfg--;
/* disable link interrupt handling during link training */
nouveau_event_put(outp->irq);
/* enable down-spreading and execute pre-train script from vbios */
dp_link_train_init(dp, outp->dpcd[3] & 0x01);
......@@ -370,12 +375,16 @@ nouveau_dp_train(struct nvkm_output_dp *outp, u32 datarate)
}
}
/* finish link training */
/* finish link training and execute post-train script from vbios */
dp_set_training_pattern(dp, 0);
if (ret < 0)
ERR("link training failed\n");
/* execute post-train script from vbios */
dp_link_train_fini(dp);
return (ret < 0) ? false : true;
/* signal completion and enable link interrupt handling */
DBG("training complete\n");
atomic_set(&outp->lt.done, 1);
wake_up(&outp->lt.wait);
nouveau_event_get(outp->irq);
}
......@@ -13,8 +13,7 @@
#define DPCD_RC0E_AUX_RD_INTERVAL 0x0000e
/* DPCD Link Configuration */
#define DPCD_LC00 0x00100
#define DPCD_LC00_LINK_BW_SET 0xff
#define DPCD_LC00_LINK_BW_SET 0x00100
#define DPCD_LC01 0x00101
#define DPCD_LC01_ENHANCED_FRAME_EN 0x80
#define DPCD_LC01_LANE_COUNT_SET 0x1f
......@@ -71,4 +70,6 @@
#define DPCD_LS0C_LANE1_POST_CURSOR2 0x0c
#define DPCD_LS0C_LANE0_POST_CURSOR2 0x03
void nouveau_dp_train(struct work_struct *);
#endif
......@@ -1457,6 +1457,24 @@ nv50_disp_intr_unk20_2(struct nv50_disp_priv *priv, int head)
if (!outp)
return;
/* we allow both encoder attach and detach operations to occur
* within a single supervisor (ie. modeset) sequence. the
* encoder detach scripts quite often switch off power to the
* lanes, which requires the link to be re-trained.
*
* this is not generally an issue as the sink "must" (heh)
* signal an irq when it's lost sync so the driver can
* re-train.
*
* however, on some boards, if one does not configure at least
* the gpu side of the link *before* attaching, then various
* things can go horribly wrong (PDISP disappearing from mmio,
* third supervisor never happens, etc).
*
* the solution is simply to retrain here, if necessary. last
* i checked, the binary driver userspace does not appear to
* trigger this situation (it forces an UPDATE between steps).
*/
if (outp->info.type == DCB_OUTPUT_DP) {
u32 soff = (ffs(outp->info.or) - 1) * 0x08;
u32 ctrl, datarate;
......@@ -1478,7 +1496,8 @@ nv50_disp_intr_unk20_2(struct nv50_disp_priv *priv, int head)
break;
}
nouveau_dp_train((void *)outp, datarate / soff);
if (nvkm_output_dp_train(outp, datarate / soff, true))
ERR("link not trained before attach\n");
}
exec_clkcmp(priv, head, 0, pclk, &conf);
......
......@@ -1138,6 +1138,7 @@ nvd0_disp_intr_unk2_2(struct nv50_disp_priv *priv, int head)
if (!outp)
return;
/* see note in nv50_disp_intr_unk20_2() */
if (outp->info.type == DCB_OUTPUT_DP) {
u32 sync = nv_rd32(priv, 0x660404 + (head * 0x300));
switch ((sync & 0x000003c0) >> 6) {
......@@ -1149,7 +1150,8 @@ nvd0_disp_intr_unk2_2(struct nv50_disp_priv *priv, int head)
break;
}
nouveau_dp_train((void *)outp, pclk);
if (nvkm_output_dp_train(outp, pclk, true))
ERR("link not trained before attach\n");
}
exec_clkcmp(priv, head, 0, pclk, &conf);
......
......@@ -28,6 +28,75 @@
#include "conn.h"
#include "dport.h"
int
nvkm_output_dp_train(struct nvkm_output *base, u32 datarate, bool wait)
{
struct nvkm_output_dp *outp = (void *)base;
bool retrain = true;
u8 link[2], stat[3];
u32 rate;
int ret, i;
/* check that the link is trained at a high enough rate */
ret = nv_rdaux(outp->base.edid, DPCD_LC00_LINK_BW_SET, link, 2);
if (ret) {
DBG("failed to read link config, assuming no sink\n");
goto done;
}
rate = link[0] * 27000 * (link[1] & DPCD_LC01_LANE_COUNT_SET);
if (rate < ((datarate / 8) * 10)) {
DBG("link not trained at sufficient rate\n");
goto done;
}
/* check that link is still trained */
ret = nv_rdaux(outp->base.edid, DPCD_LS02, stat, 3);
if (ret) {
DBG("failed to read link status, assuming no sink\n");
goto done;
}
if (stat[2] & DPCD_LS04_INTERLANE_ALIGN_DONE) {
for (i = 0; i < (link[1] & DPCD_LC01_LANE_COUNT_SET); i++) {
u8 lane = (stat[i >> 1] >> ((i & 1) * 4)) & 0x0f;
if (!(lane & DPCD_LS02_LANE0_CR_DONE) ||
!(lane & DPCD_LS02_LANE0_CHANNEL_EQ_DONE) ||
!(lane & DPCD_LS02_LANE0_SYMBOL_LOCKED)) {
DBG("lane %d not equalised\n", lane);
goto done;
}
}
retrain = false;
} else {
DBG("no inter-lane alignment\n");
}
done:
if (retrain || !atomic_read(&outp->lt.done)) {
/* no sink, but still need to configure source */
if (outp->dpcd[DPCD_RC00_DPCD_REV] == 0x00) {
outp->dpcd[DPCD_RC01_MAX_LINK_RATE] =
outp->base.info.dpconf.link_bw;
outp->dpcd[DPCD_RC02] =
outp->base.info.dpconf.link_nr;
}
atomic_set(&outp->lt.done, 0);
schedule_work(&outp->lt.work);
} else {
nouveau_event_get(outp->irq);
}
if (wait) {
if (!wait_event_timeout(outp->lt.wait,
atomic_read(&outp->lt.done),
msecs_to_jiffies(2000)))
ret = -ETIMEDOUT;
}
return ret;
}
static void
nvkm_output_dp_enable(struct nvkm_output_dp *outp, bool present)
{
......@@ -38,12 +107,14 @@ nvkm_output_dp_enable(struct nvkm_output_dp *outp, bool present)
DBG("aux power -> always\n");
outp->present = true;
}
nvkm_output_dp_train(&outp->base, 0, true);
} else {
if (outp->present) {
nouveau_i2c(port)->release_pad(port);
DBG("aux power -> demand\n");
outp->present = false;
}
atomic_set(&outp->lt.done, 0);
}
}
......@@ -78,7 +149,7 @@ nvkm_output_dp_service_work(struct work_struct *work)
}
if (type & NVKM_I2C_IRQ) {
nouveau_event_get(outp->irq);
nvkm_output_dp_train(&outp->base, 0, true);
send |= NVKM_HPD_IRQ;
}
......@@ -159,6 +230,11 @@ nvkm_output_dp_create_(struct nouveau_object *parent,
DBG("bios dp %02x %02x %02x %02x\n", outp->version, hdr, cnt, len);
/* link training */
INIT_WORK(&outp->lt.work, nouveau_dp_train);
init_waitqueue_head(&outp->lt.wait);
atomic_set(&outp->lt.done, 0);
/* link maintenance */
ret = nouveau_event_new(i2c->ntfy, NVKM_I2C_IRQ, outp->base.edid->index,
nvkm_output_dp_service, outp, &outp->irq);
......
......@@ -18,6 +18,12 @@ struct nvkm_output_dp {
atomic_t pending;
bool present;
u8 dpcd[16];
struct {
struct work_struct work;
wait_queue_head_t wait;
atomic_t done;
} lt;
};
#define nvkm_output_dp_create(p,e,c,b,i,d) \
......@@ -54,6 +60,6 @@ struct nvkm_output_dp_impl {
int (*drv_ctl)(struct nvkm_output_dp *, int ln, int vs, int pe, int pc);
};
int nouveau_dp_train(struct nvkm_output_dp *, u32 rate);
int nvkm_output_dp_train(struct nvkm_output *, u32 rate, bool wait);
#endif
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