[SWDEV-538308] CPER CLI 20 limit bug (#499)

The bug was reproduced like this.

In terminal #1, run command:
sudo amd-smi ras --cper --gpu 6 --severity all --folder /tmp/cper_dump --follow 

In terminal #2, inject errors:
while true; do sudo amdgpuras -b 7 -s 1 -m 6 -t 2; sleep 2; done

The terminal #1 starts dumping cper entry information that it captures. After 20 entries have been captured, open terminal #3 and run same command as terminal #1:
sudo amd-smi ras --cper --gpu 6 --severity all --folder /tmp/cper_dump --follow 

From terminal #3, there will be no output, even when terminal #1 continues capturing and printing information.

The fix:

Since we already have more than 20 CPER entries available in the GPU buffer, when we run the command from terminal #3 to start capturing from the beginning and pass 20 buffers to copy entries to, the C++ API returns a code saying there is more data available.

The Python CLI should not treat this as an error, but should continue to print what the API returned.

---------

Signed-off-by: Oosman Saeed <oossaeed@amd.com>

py-interface/amdsmi_interface.py

@@ -2435,7 +2435,7 @@ def amdsmi_get_gpu_cper_entries(
     severity_mask: int,
     buffer_size: int = 4 * 1048576,
     cursor: int = 0
-) -> Tuple[Dict[str, Any], int, List[Dict[str, Any]]]:
+) -> Tuple[Dict[str, Any], int, List[Dict[str, Any]], int]:
 
     if not isinstance(processor_handle, amdsmi_wrapper.amdsmi_processor_handle):
         raise AmdSmiParameterException(
@@ -2445,15 +2445,16 @@ def amdsmi_get_gpu_cper_entries(
     # Allocate a buffer for CPER data.
     buf = ctypes.create_string_buffer(buffer_size)
     buf_size = ctypes.c_uint64(buffer_size)
-    entry_count = ctypes.c_uint64(20)
+    num_cper_hdrs = 20
+    entry_count = ctypes.c_uint64(num_cper_hdrs)
     cur = ctypes.c_uint64(cursor)
 
     # Allocate a pointer for the CPER header array.
-    cper_hdrs_array = (POINTER(amdsmi_wrapper.amdsmi_cper_hdr_t) * 20)()
-    cper_hdrs = ctypes.cast(cper_hdrs_array, POINTER(POINTER(amdsmi_wrapper.amdsmi_cper_hdr_t)))
+    cper_hdrs_array = (ctypes.POINTER(amdsmi_wrapper.amdsmi_cper_hdr_t) * num_cper_hdrs)()
+    cper_hdrs = ctypes.cast(cper_hdrs_array, ctypes.POINTER(ctypes.POINTER(amdsmi_wrapper.amdsmi_cper_hdr_t)))
 
     # Call the underlying AMD-SMI API.
-    ret = amdsmi_wrapper.amdsmi_get_gpu_cper_entries(
+    status_code = amdsmi_wrapper.amdsmi_get_gpu_cper_entries(
         processor_handle,
         ctypes.c_uint32(severity_mask),
         buf,
@@ -2462,8 +2463,8 @@ def amdsmi_get_gpu_cper_entries(
         ctypes.byref(entry_count),
         ctypes.byref(cur)
     )
-    if ret != amdsmi_wrapper.AMDSMI_STATUS_SUCCESS:
-        raise AmdSmiLibraryException(ret)
+    if status_code not in {amdsmi_wrapper.AMDSMI_STATUS_SUCCESS, amdsmi_wrapper.AMDSMI_STATUS_MORE_DATA}:
+        raise AmdSmiLibraryException(status_code)
 
     entries = {}
     cper_data = []
@@ -2518,7 +2519,7 @@ def amdsmi_get_gpu_cper_entries(
         entries[i] = cper_entry.copy()
         offset += entry_ptr.contents.record_length  # Use the actual record length to advance the offset.
 
-    return entries, cur.value, cper_data
+    return entries, cur.value, cper_data, status_code
 
 
 def amdsmi_get_afids_from_cper(