Support page directories outside PRAMIN or in SYS_MEM

- Re-read PRAMIN configuration after update to verify change applies
- Return a page_dir_config_t rather than just an address and page.
  table version from `get_bar2_pdb()`.
- Less verbose logging for MMU-related functions by default.
- Perform all conversion from SYS_MEM/VID_MEM addresses to kernel
  addresses inside the translation functions, via the new function
  'pd_deref()`.
- Support use of an I/O MMU, page tables/directories outside the
  current PRAMIN window, and page tables/directories arbitrarially
  located in SYS_MEM or VID_MEM on different levels of the same tree.
- Heavily improve documentation and add references for Version 1 and
  Version 0 page tables.
- Improve logging in `runlist.c` to include runlist and chip IDs.
- Update all users of search_page_directory* to use the new API.
- Remove now-unused supporting functions from `mmu.c`.

Tested on GTX 970, GTX 1060 3GB, Jetson TX2, Titan V, Jetson Xavier,
and RTX 2080 Ti.

1 files changed, 19 insertions, 14 deletions

diff --git a/runlist.c b/runlist.c
index c725e77..2eee01c 100644
--- a/runlist.c
+++ b/runlist.c
@@ -9,7 +9,8 @@
 
 // Uncomment to, upon BAR2 access failure, return a PRAMIN-based runlist pointer
 // **If enabled, PRAMIN may not be otherwise used while walking the runlist!**
-#define FALLBACK_TO_PRAMIN
+// Runlists can only be printed on the Jetson TX2 if this is enabled.
+//#define FALLBACK_TO_PRAMIN
 
 /* Get runlist head and info (incl. length)
   @param rl_id   Which runlist to obtain?
@@ -20,6 +21,7 @@ int get_runlist_iter(struct nvdebug_state *g, int rl_id, struct runlist_iter *rl
         uint64_t runlist_iova;
         enum INST_TARGET runlist_target;
         uint16_t runlist_len;
+        int err;
 #ifdef FALLBACK_TO_PRAMIN
         int off;
 #endif // FALLBACK_TO_PRAMIN
@@ -33,9 +35,9 @@ int get_runlist_iter(struct nvdebug_state *g, int rl_id, struct runlist_iter *rl
                         return -EIO;
                 runlist_iova = ((uint64_t)rl.ptr) << 12;
                 runlist_target = rl.target;
-                printk(KERN_INFO "[nvdebug] Runlist %d: %d entries @ %llx in %s (config raw: %#018llx)\n",
-                           rl_id, rl.len, runlist_iova, target_to_text(rl.target), rl.raw);
                 runlist_len = rl.len;
+                printk(KERN_INFO "[nvdebug] Runlist %d for %x: %d entries @ %llx in %s (config raw: %#018llx)\n",
+                           rl_id, g->chip_id, rl.len, runlist_iova, target_to_text(rl.target), rl.raw);
         } else if (g->chip_id < NV_CHIP_ID_AMPERE) {
                 runlist_base_tu102_t base;
                 runlist_submit_tu102_t submit;
@@ -46,6 +48,8 @@ int get_runlist_iter(struct nvdebug_state *g, int rl_id, struct runlist_iter *rl
                 runlist_iova = ((uint64_t)base.ptr) << 12;
                 runlist_target = base.target;
                 runlist_len = submit.len;
+                printk(KERN_INFO "[nvdebug] Runlist %d for %x: %d entries @ %llx in %s (config raw: %#018llx %#018llx)\n",
+                           rl_id, g->chip_id, submit.len, runlist_iova, target_to_text(runlist_target), base.raw, submit.raw);
         }
         // Return early on an empty runlist
         if (!runlist_len)
@@ -53,24 +57,25 @@ int get_runlist_iter(struct nvdebug_state *g, int rl_id, struct runlist_iter *rl
 
         // If the runlist is in VID_MEM, search the BAR2/3 page tables for a mapping
         if (runlist_target == TARGET_VID_MEM) {
-                void __iomem *bar2_page_dir;
-                bool pdb_is_ver2;
                 uint64_t runlist_bar_vaddr;
+                page_dir_config_t pd_config;
 
-                if (get_bar2_pdb(g, &bar2_page_dir, &pdb_is_ver2) < 0)
-                        return -EIO;
+                if ((err = get_bar2_pdb(g, &pd_config)) < 0)
+                        goto attempt_pramin_access;
 
-                if (pdb_is_ver2)
-                        runlist_bar_vaddr = search_page_directory(g, bar2_page_dir, phy2PRAMIN, runlist_iova);
+                if (pd_config.is_ver2)
+                        runlist_bar_vaddr = search_page_directory(g, pd_config, runlist_iova);
                 else
-                        runlist_bar_vaddr = search_v1_page_directory(g, bar2_page_dir, phy2PRAMIN, runlist_iova);
+                        runlist_bar_vaddr = search_v1_page_directory(g, pd_config, runlist_iova);
                 if (!runlist_bar_vaddr) {
-                        printk(KERN_WARNING "[nvdebug] Unable to find runlist mapping in BAR2/3 page tables.\n");
+                        printk(KERN_WARNING "[nvdebug] Unable to find runlist %d mapping in BAR2/3 page tables for %x.\n", rl_id, g->chip_id);
+                        err = -EOPNOTSUPP;
                         goto attempt_pramin_access;
                 }
-                printk(KERN_INFO "[nvdebug] Runlist @ %llx in BAR2 virtual address space.\n", runlist_bar_vaddr);
+
+                printk(KERN_INFO "[nvdebug] Runlist %d for %x @ %llx in BAR2 virtual address space.\n", rl_id, g->chip_id, runlist_bar_vaddr);
                 if (!g->bar2) {
-                        printk(KERN_WARNING "[nvdebug] BAR2/3 not mapped.\n");
+                        printk(KERN_WARNING "[nvdebug] BAR2/3 not mapped for %x.\n", g->chip_id);
                         return -ENODEV;
                 }
                 rl_iter->curr_entry = g->bar2 + runlist_bar_vaddr;
@@ -91,7 +96,7 @@ attempt_pramin_access:
         rl_iter->len = runlist_len;
         return 0;
 #else
-        return -EOPNOTSUPP;
+        return err;
 #endif // FALLBACK_TO_PRAMIN
 }