Support printing the runlist and channels on Ampere+ GPUs

**Modifes the user API from `cat /proc/gpuX/runlist0` to
`cat /proc/gpuX/runlist0/runlist` to support runlist-scoped
registers**

- Count number of runlists via Ampere-style PTOP parsing.
- Create a ProcFS directory for each runlist, and create the runlist
  printing file in this directory.
- Document the newly-added/-formatted Runlist RAM and Channel RAM
  registers.
- Add a helper function `get_runlist_ram()` to obtain the location
  of each runlist's registers.
- Support printing Ampere-style Channel RAM entries.

Tested on Jetson Orin (ga10b), A100, H100, and AD102 (RTX 6000 Ada)

1 files changed, 50 insertions, 14 deletions

diff --git a/runlist_procfs.c b/runlist_procfs.c
index 8152463..c1cfc87 100644
--- a/runlist_procfs.c
+++ b/runlist_procfs.c
@@ -8,11 +8,11 @@
 
 #ifdef DETAILED_CHANNEL_INFO
 /* Print channel details using PCCSR (Programmable Channel Control System RAM?)
- * @param s      Pointer to state from seq_file subsystem to pass to seq_printf
- * @param g      Pointer to our internal GPU state
- * @param chid   ID of channel to print details on, range [0, 512)
- * @param prefix Text string to prefix each line with, or empty string
- */
+  @param s      Pointer to state from seq_file subsystem to pass to seq_printf
+  @param g      Pointer to our internal GPU state
+  @param chid   ID of channel to print details on, range [0, 512)
+  @param prefix Text string to prefix each line with, or empty string
+*/
 static int runlist_detail_seq_show_chan(struct seq_file *s, struct nvdebug_state *g, uint32_t chid, char *prefix) {
         channel_ctrl_t chan;
         uint64_t instance_ptr;
@@ -21,7 +21,7 @@ static int runlist_detail_seq_show_chan(struct seq_file *s, struct nvdebug_state
                 return -EIO;
         instance_ptr = (uint64_t)chan.inst_ptr << 12;
         // Don't print write-only fields
-        seq_printf(s, "%s+- Channel Info %-4d -+\n", prefix, chid);
+        seq_printf(s, "%s|= Channel Info ======|\n", prefix);
         seq_printf(s, "%s| Enabled:           %d|\n", prefix, chan.enable);
         seq_printf(s, "%s| Next:              %d|\n", prefix, chan.next);
         seq_printf(s, "%s| PBDMA Faulted:     %d|\n", prefix, chan.pbdma_faulted);
@@ -32,7 +32,37 @@ static int runlist_detail_seq_show_chan(struct seq_file *s, struct nvdebug_state
         seq_printf(s, "%s|   %#018llx|\n", prefix, instance_ptr);
         seq_printf(s, "%s| %20s|\n", prefix, target_to_text(chan.inst_target));
         seq_printf(s, "%s| Instance bound:    %d|\n", prefix, chan.inst_bind);
-        seq_printf(s, "%s+---------------------+\n", prefix);
+        return 0;
+}
+
+/* `runlist_detail_seq_show_chan()`, but for Ampere+
+  @param runlist_pri_base Base of the RLRAM region for this runlist
+
+  `runlist_pri_base` is necessary, since Channel RAM is now per-runlist on
+  Ampere+, and its location is configured in Runlist RAM.
+*/
+static int runlist_detail_seq_show_chan_ga100(struct seq_file *s, struct nvdebug_state *g, uint32_t chid, char *prefix, uint32_t runlist_pri_base) {
+        runlist_channel_config_t channel_config;
+        channel_ctrl_ga100_t chan;
+
+        // Channel RAM is subsidiary to Runlist RAM (ie. per-runlist) on Ampere+
+        if ((channel_config.raw = nvdebug_readl(g, runlist_pri_base + NV_RUNLIST_CHANNEL_CONFIG_GA100)) == -1)
+                return -EIO;
+        if ((chan.raw = nvdebug_readl(g, (((uint32_t)channel_config.bar0_offset << 4) + chid * 4))) == -1)
+                return -EIO;
+        seq_printf(s, "%s|= Channel Info ======|\n", prefix);
+        seq_printf(s, "%s| Enabled:           %d|\n", prefix, chan.enable);
+        seq_printf(s, "%s| Next:              %d|\n", prefix, chan.next);
+        seq_printf(s, "%s| Busy:              %d|\n", prefix, chan.busy);
+        seq_printf(s, "%s| PBDMA Faulted:     %d|\n", prefix, chan.pbdma_faulted);
+        seq_printf(s, "%s| ENG Faulted:       %d|\n", prefix, chan.eng_faulted);
+        seq_printf(s, "%s| On PBDMA:          %d|\n", prefix, chan.on_pbdma);
+        seq_printf(s, "%s| On ENG:            %d|\n", prefix, chan.on_eng);
+        seq_printf(s, "%s| Pending:           %d|\n", prefix, chan.pending);
+        seq_printf(s, "%s| CTX Reload:        %d|\n", prefix, chan.ctx_reload);
+        seq_printf(s, "%s| PBDMA Busy:        %d|\n", prefix, chan.pbdma_busy);
+        seq_printf(s, "%s| ENG Busy:          %d|\n", prefix, chan.eng_busy);
+        seq_printf(s, "%s| Acquire Fail:      %d|\n", prefix, chan.acquire_fail);
         return 0;
 }
 #endif
@@ -118,27 +148,33 @@ static int runlist_file_seq_show(struct seq_file *s, void *raw_rl_iter) {
         } else {
                 char *indt = "";
                 u64 instance_ptr = 0;
-
                 if (rl_iter->entries_left_in_tsg)
                         indt = "  ";
-#ifdef DETAILED_CHANNEL_INFO
-                runlist_detail_seq_show_chan(s, g, chid(g, entry), indt);
-                return 0;
-#endif
                 // Reconstruct pointer to channel instance block
                 if (g->chip_id >= NV_CHIP_ID_VOLTA) {
                         instance_ptr = ((struct gv100_runlist_chan*)entry)->inst_ptr_hi;
                         instance_ptr <<= 32;
                 }
                 instance_ptr |= inst_ptr_lo(g, entry) << 12;
-
+                // Print channel information from runlist
                 seq_printf(s, "%s+- Channel Entry %-4d-+\n", indt, chid(g, entry));
                 if (g->chip_id >= NV_CHIP_ID_VOLTA)
                         seq_printf(s, "%s| Runqueue Selector: %d|\n", indt,
-                                   ((struct gv100_runlist_chan*)entry)->runqueue_selector);
+                                   ((struct gv100_runlist_chan*)entry)->runqueue_selector);
+                // Not populated on Kepler [ex: gk104 in Bonham (Quadro K5000)], and
+                // populated but unused on Pascal [ex: gp104 in Bonham (GTX 1080 Ti)].
+                // (The aperture field may be incorrectly populated as INVALID, but the
+                // context still works on the aformentioned Pascal GPU.)
                 seq_printf(s, "%s| Instance PTR:       |\n", indt);
                 seq_printf(s, "%s|   %#018llx|\n", indt, instance_ptr);
                 seq_printf(s, "%s| %20s|\n", indt, target_to_text(inst_target(g, entry)));
+#ifdef DETAILED_CHANNEL_INFO
+                // Print channel info from PCCSR/Channel RAM and the instance block
+                if (g->chip_id < NV_CHIP_ID_AMPERE)
+                        runlist_detail_seq_show_chan(s, g, chid(g, entry), indt);
+                else
+                        runlist_detail_seq_show_chan_ga100(s, g, chid(g, entry), indt, rl_iter->runlist_pri_base);
+#endif
                 seq_printf(s, "%s+---------------------+\n", indt);
         }
         return 0;