Changes between Version 22 and Version 23 of Component/Vci Multi Ahci

Timestamp:

Apr 28, 2015, 6:57:25 PM (9 years ago)

Author:

alain

Comment:

--

Component/Vci Multi Ahci

@@ -37 +37 @@
 == 3) Command Table ==
 
-There is one Command Table for each Command descriptor. For a given command, there is one single LBA (Logic Bloc Address) on the block device, coded on 48 bits, but the source (or destination) memory buffer can be split in a variable number of contiguous buffers. Therefore, the Command Table contains two parts: a fixed size Header, defining the LBA, and an array of buffer descriptors containing up to 248 buffer descriptors. A Command Table occupies 4 Kbytes, and must be aligned on a 4 Kbytes boundary. It is defined by the following C structures: 
+There is one Command Table for each Command descriptor. For a given command, there is one single LBA (Logic Bloc Address) on the block device, coded on 48 bits, but the source (or destination) memory buffer can be split in a variable number of contiguous buffers. Therefore, the Command Table contains two parts: a fixed size Header, defining the LBA, followed by a variable size array of fixed size buffer descriptors.
+The Command Table describing one command is defined by the two following C structures: 
 {{{
-typedef struct hba_cmd_table_s  // size = 4 Kbytes
-{
 
-    hba_cmd_header_t   header;      // contains LBA
-    hba_cmd_buffer_t   buffer[248]; // 248 buffers max
-
-} hba_cmd_table_t;
-
-typedef struct hba_cmd_header_s // size = 128 bytes
+typedef struct hba_cmd_header_s // size = 16 bytes
 {
     unsigned int       res0;        // reserved 
@@ -57 +51 @@
     unsigned char      lba4;        // LBA 39:32
     unsigned char      lba5;        // LBA 47:40
+    unsigned char      res1;        // reserved
     unsigned char      res2;        // reserved
-    unsigned int       res[29];     // reserved 
+    unsigned int       res3;        // reserved 
 } hba_cmd_header_t;