Refactored various systems and debugged minor issues

 - Added device_info_iter
 - Merged functions in device_info_procfs.c
 - Separated device_info data structs by version in nvdebug.h
 - Fixed issue with device_info runlist ID data

3 files changed, 69 insertions, 81 deletions

diff --git a/device_info_procfs.c b/device_info_procfs.c
index 3cf4bc9..5ddf240 100644
--- a/device_info_procfs.c
+++ b/device_info_procfs.c
@@ -27,61 +27,57 @@ struct file_operations nvdebug_read_reg32_file_ops = {
         .llseek = default_llseek,
 };
 
+typedef struct {
+        int total_entries;
+        int index;
+        int type_of_next_entry;
+} device_info_iter;
+
 //// ==v== PTOP_DEVICE_INFO ==v== ////
 
+static void* device_info_seq_start_backend(struct seq_file *s, loff_t *pos, int initial_entry_value, int total_entries) {
+        static device_info_iter idx;
+        // If start of sequence, reset `idx`
+        if (*pos == 0) {
+                idx.index = 0;
+                idx.type_of_next_entry = initial_entry_value;
+        }
+        idx.total_entries = total_entries;
+        // Number of possible info entries is fixed, and list is sparse
+        if (idx.index >= idx.total_entries)
+                return NULL;
+        return &idx;
+}
+
 // Called to start or resume a sequence. Prior to 4.19, *pos is unreliable.
 // Initializes iterator `idx` state and returns it. Ends sequence on NULL.
 static void* device_info_file_seq_start_previous(struct seq_file *s, loff_t *pos) {
-        static int idx;
-        // If start of sequence, reset `idx`
-        if (*pos == 0)
-                idx = 0;
-        // Number of possible info entries is fixed, and list is sparse
-        if (idx >= NV_PTOP_DEVICE_INFO__SIZE_1_PREVIOUS)
-                return NULL;
-        return &idx;
+        return device_info_seq_start_backend(s, pos, -1, NV_PTOP_DEVICE_INFO__SIZE_1_PREVIOUS);
 }
 
 static void* device_info_file_seq_start_ampere(struct seq_file *s, loff_t *pos) {
-        static int idx;
-        // If start of sequence, reset `idx`
-        if (*pos == 0)
-                idx = 0;
-        struct nvdebug_state *g = &g_nvdebug_state[seq2gpuidx(s)];
-        // Number of possible info entries is fixed, and list is sparse
-        if (idx >= NV_PTOP_DEVICE_INFO__SIZE_1_AMPERE(g))
-                return NULL;
-        return &idx;
+        struct nvdebug_state *g = &g_nvdebug_state[seq2gpuidx(s)];
+        return device_info_seq_start_backend(s, pos, 0, NV_PTOP_DEVICE_INFO__SIZE_1_AMPERE(g));
 }
 
 // Steps to next record. Returns new value of `idx`.
 // Calls show() on non-NULL return
-static void* device_info_file_seq_next_previous(struct seq_file *s, void *idx,
+static void* device_info_file_seq_next(struct seq_file *s, void *idx,
                                        loff_t *pos) {
+        device_info_iter *idx_iter = (device_info_iter*)idx;
         (*pos)++; // Required by seq interface
         // Number of possible info entries is fixed, and list is sparse
-        if ((*(int*)idx)++ >= NV_PTOP_DEVICE_INFO__SIZE_1_PREVIOUS)
+        if (idx_iter->index++ >= idx_iter->total_entries)
                 return NULL;
         return idx;
 }
 
-// Steps to next record. Returns new value of `idx`.
-// Calls show() on non-NULL return
-static void* device_info_file_seq_next_ampere(struct seq_file *s, void *idx,
-                                       loff_t *pos) {
-        (*pos)++; // Required by seq interface
-        // Number of possible info entries is fixed, and list is sparse
-        struct nvdebug_state *g = &g_nvdebug_state[seq2gpuidx(s)];
-        if ((*(int*)idx)++ >= NV_PTOP_DEVICE_INFO__SIZE_1_AMPERE(g))
-                    return NULL;
-        return idx;
-}
-
 // Print info at index *idx. Returns non-zero on error.
 static int device_info_file_seq_show_previous(struct seq_file *s, void *idx) {
-        ptop_device_info_t curr_info;
+        device_info_iter *idx_iter = (device_info_iter*)idx;
+        ptop_device_info_previous_t curr_info;
         struct nvdebug_state *g = &g_nvdebug_state[seq2gpuidx(s)];
-        curr_info.raw = nvdebug_readl(g, NV_PTOP_DEVICE_INFO_PREVIOUS(*(int*)idx));
+        curr_info.raw = nvdebug_readl(g, NV_PTOP_DEVICE_INFO_PREVIOUS(idx_iter->index));
         // Check for read errors
         if (curr_info.raw == -1)
                 return -EIO;
@@ -129,54 +125,42 @@ static int device_info_file_seq_show_previous(struct seq_file *s, void *idx) {
 
 // Print info at index *idx for Ampere GPUs. Returns non-zero on error.
 static int device_info_file_seq_show_ampere(struct seq_file *s, void *idx) {
-        ptop_device_info_t curr_info;
+        device_info_iter *idx_iter = (device_info_iter*)idx;
+        ptop_device_info_ampere_t curr_info;
         struct nvdebug_state *g = &g_nvdebug_state[seq2gpuidx(s)];
-        curr_info.raw = nvdebug_readl(g, NV_PTOP_DEVICE_INFO_AMPERE(*(int*)idx));
+        curr_info.raw = nvdebug_readl(g, NV_PTOP_DEVICE_INFO_AMPERE(idx_iter->index));
         // Check for read errors
         if (curr_info.raw == -1)
                 return -EIO;
         // The info_type field is not available in the Ampere device_info data, so it must be inferred
-        int info_type = -1;
-        if(curr_info.raw) {
-                for(int i = 0; i < NV_PTOP_DEVICE_INFO_TYPE_COUNT; i++) {
-                        if(*(int*)idx == i) {
-                                info_type = i;
-                                break;
-                        }
-                        ptop_device_info_t prev_info;
-                        prev_info.raw = nvdebug_readl(g, NV_PTOP_DEVICE_INFO_AMPERE(*(int*)idx - i - 1));
-                        if(!prev_info.raw || !prev_info.has_next_entry_ampere) {
-                                info_type = i;
-                                break;
-                        }
-                }
-        }
+        int info_type = curr_info.raw ? idx_iter->type_of_next_entry : -1;
         // Parse and print the data
         switch(info_type) {
         case 0:
-                seq_printf(s, "|           instance %d\n", curr_info.inst_id_ampere);
-                seq_printf(s, "| Fault ID:        %3d\n", curr_info.fault_id_ampere);
-                seq_printf(s, "| Engine Type:      %2d (", curr_info.engine_type_ampere);
-                if (curr_info.engine_type_ampere < ENGINE_TYPES_LEN)
-                        seq_printf(s, "%s)\n", ENGINE_TYPES_NAMES[curr_info.engine_type_ampere]);
+                seq_printf(s, "|           instance %d\n", curr_info.inst_id);
+                seq_printf(s, "| Fault ID:        %3d\n", curr_info.fault_id);
+                seq_printf(s, "| Engine Type:      %2d (", curr_info.engine_type);
+                if (curr_info.engine_type < ENGINE_TYPES_LEN)
+                        seq_printf(s, "%s)\n", ENGINE_TYPES_NAMES[curr_info.engine_type]);
                 else
                         seq_printf(s, "Unknown Engine, introduced post-Ampere)\n");
                 break;
         case 1:
-                seq_printf(s, "| BAR0 Base %#.8x\n", curr_info.pri_base_ampere << 12);
-                seq_printf(s, "| Reset ID:         %2d\n", curr_info.reset_enum_ampere);
+                seq_printf(s, "| BAR0 Base %#.8x\n", curr_info.pri_base << 12);
+                seq_printf(s, "| Reset ID:         %2d\n", curr_info.reset_enum);
                 break;
         case 2:
-                seq_printf(s, "| Host's Engine ID: %2d\n", curr_info.engine_enum_ampere);
-                seq_printf(s, "| Runlist ID:       %2d\n", curr_info.runlist_enum_ampere);
+                seq_printf(s, "| Host's Engine ID: %2d\n", curr_info.engine_enum);
+                seq_printf(s, "| Runlist ID:       %2d\n", curr_info.runlist_enum);
                 break;
         default:
                 // Device info records are sparse, so skip unset or unknown ones
                 return 0;
         }
-
+        if(info_type != -1) idx_iter->type_of_next_entry++;
         // Draw a line between each device entry
-        if (!curr_info.has_next_entry_ampere) {
+        if (!curr_info.has_next_entry) {
+                idx_iter->type_of_next_entry = 0;
                 seq_printf(s, "+---------------------+\n");
         }
         return 0;
@@ -189,14 +173,14 @@ static void device_info_file_seq_stop(struct seq_file *s, void *idx) {
 
 static const struct seq_operations device_info_file_seq_ops_previous = {
         .start = device_info_file_seq_start_previous,
-        .next = device_info_file_seq_next_previous,
+        .next = device_info_file_seq_next,
         .stop = device_info_file_seq_stop,
         .show = device_info_file_seq_show_previous,
 };
 
 static const struct seq_operations device_info_file_seq_ops_ampere = {
         .start = device_info_file_seq_start_ampere,
-        .next = device_info_file_seq_next_ampere,
+        .next = device_info_file_seq_next,
         .stop = device_info_file_seq_stop,
         .show = device_info_file_seq_show_ampere,
 };
diff --git a/nvdebug.h b/nvdebug.h
index d6b7358..c45e460 100644
--- a/nvdebug.h
+++ b/nvdebug.h
@@ -567,25 +567,29 @@ static const char* const ENGINE_TYPES_NAMES[ENGINE_TYPES_LEN] = {
 #define NV_PTOP_DEVICE_INFO_TYPE_COUNT 3