Grow largest frame length to 512 bytes

doc/framing_protocol/framing_protocol.md

@@ -125,12 +125,12 @@ The bits in the command header byte should be interpreted as:
 0. 1 byte
 1. 4 bytes
 2. 32 bytes
-3. 128 bytes
+3. 512 bytes
 
 Note that the number of bytes indicated by the command data length field
 does **not** include the command header byte. This means that a complete
-command frame, with a header indicating a data length of 128 bytes, is
-129 bytes in length.
+command frame, with a header indicating a data length of 512 bytes, is
+512+1 bytes in length.
 
 Note that the host sets the frame ID tag. The ID tag in a given command
 MUST be preserved in the corresponding response to the command.
@@ -148,7 +148,7 @@ Some examples to clarify endpoints and commands:
   data. The single byte could indicate action such as reading from the
   TRNG or resetting the application_fpga.
 
-* 0x13: A command to the FW in the application_fpga with 128 bytes of
+* 0x13: A command to the FW in the application_fpga with 512 bytes of
   data. The data could for example be parts of an application binary to
   be loaded into the program memory.
 
@@ -179,13 +179,13 @@ The bits in the response header byte should be interpreted as:
 0. 1 byte
 1. 4 bytes
 2. 32 bytes
-3. 128 bytes
+3. 512 bytes
 
 
 Note that the number of bytes indicated by the response data length field
 does **not** include the response header byte. This means that a complete
-response frame, with a header indicating a data length of 128 bytes, is
-129 bytes in length.
+response frame, with a header indicating a data length of 512 bytes, is
+512+1 bytes in length.
 
 Note that the ID in a response MUST be the same ID as was present in the
 header of the command being responded to.
@@ -205,7 +205,7 @@ less available for the "payload" of the response.
   responds with a single byte of data.
 
 * 0x1b: A successful command to the application running in the
-  application_fpga. The response contains 128 bytes of data, for example
+  application_fpga. The response contains 512 bytes of data, for example
   an EdDSA Ed25519 signature.
 
 

doc/system_description/software.md

@@ -248,6 +248,7 @@ The commands look like this:
 | *name*           | *size (bytes)* | *comment*                                |
 |------------------|----------------|------------------------------------------|
 | Header           | 1              | Framing protocol header including length |
+|                  |                | of the rest of the frame                 |
 | Command/Response | 1              | Any of the below commands or responses   |
 | Data             | n              | Any additional data                      |
 
@@ -294,10 +295,11 @@ Response to `FW_CMD_LOAD_APP`
 
 | *name* | *size (bytes)* | *comment*           |
 |--------|----------------|---------------------|
-| data   | 127            | Raw binary app data |
+| data   | 511            | Raw binary app data |
 
-Load 127 bytes of raw app binary into device RAM. Should be sent
-consecutively over the complete raw binary.
+Load 511 bytes of raw app binary into device RAM. Should be sent
+consecutively over the complete raw binary. (512 == largest frame
+length minus the command byte).
 
 #### `FW_RSP_LOAD_APP_DATA` (0x06)
 
@@ -362,9 +364,9 @@ host <-
 
 ```
 host ->
-  u8 CMD[1 + 128];
+  u8 CMD[1 + 512];
 
-  CMD[0].len = 128  // command frame format
+  CMD[0].len = 512  // command frame format
   CMD[1]     = 0x03 // FW_CMD_LOAD_APP
 
   CMD[2..6]  = APP_SIZE
@@ -383,14 +385,14 @@ host <-
 
   RSP[3..]   = 0
 
-repeat ceil(APP_SIZE / 127) times:
+repeat ceil(APP_SIZE / 511) times:
 host ->
-  u8 CMD[1 + 128];
+  u8 CMD[1 + 512];
 
-  CMD[0].len = 128  // command frame format
+  CMD[0].len = 512  // command frame format
   CMD[1]     = 0x05 // FW_CMD_LOAD_APP_DATA
 
-  CMD[2..]   = APP_DATA (127 bytes of app data, pad with zeros)
+  CMD[2..]   = APP_DATA (511 bytes of app data, pad with zeros)
 
 host <-
   u8 RSP[1 + 4]
@@ -407,9 +409,9 @@ Except response from last chunk of app data which is:
 
 ```
 host <-
-  u8 RSP[1 + 4]
+  u8 RSP[1 + 512]
 
-  RSP[0].len = 128   // command frame format
+  RSP[0].len = 512  // command frame format
   RSP[1]     = 0x07 // FW_RSP_LOAD_APP_DATA_READY
 
   RSP[2]     = STATUS

hw/application_fpga/fw/tk1/main.c

@@ -291,7 +291,7 @@ int main()
 
 		case FW_CMD_LOAD_APP:
 			htif_puts("cmd: load-app(size, uss)\n");
-			if (hdr.len != 128) {
+			if (hdr.len != 512) {
 				// Bad length
 				rsp[0] = STATUS_BAD;
 				fwreply(hdr, FW_RSP_LOAD_APP, rsp);
@@ -333,7 +333,7 @@ int main()
 
 		case FW_CMD_LOAD_APP_DATA:
 			htif_puts("cmd: load-app-data\n");
-			if (hdr.len != 128 || (state != FW_STATE_INIT_LOADING &&
+			if (hdr.len != 512 || (state != FW_STATE_INIT_LOADING &&
 					       state != FW_STATE_LOADING)) {
 				// Bad cmd length or state
 				rsp[0] = STATUS_BAD;
@@ -342,8 +342,8 @@ int main()
 			}
 
 			int nbytes;
-			if (left > 127) {
-				nbytes = 127;
+			if (left > (512 - 1)) {
+				nbytes = 512 - 1;
 			} else {
 				nbytes = left;
 			}

hw/application_fpga/fw/tk1/proto.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2022 - Tillitis AB
+ * Copyright (C) 2022, 2023 - Tillitis AB
  * SPDX-License-Identifier: GPL-2.0-only
  */
 
@@ -47,8 +47,8 @@ int parseframe(uint8_t b, struct frame_header *hdr)
 	case LEN_32:
 		hdr->len = 32;
 		break;
-	case LEN_128:
-		hdr->len = 128;
+	case LEN_512:
+		hdr->len = 512;
 		break;
 	default:
 		// Unknown length
@@ -82,8 +82,8 @@ void fwreply(struct frame_header hdr, enum fwcmd rspcode, uint8_t *buf)
 		break;
 
 	case FW_RSP_LOAD_APP_DATA_READY:
-		len = LEN_128;
-		nbytes = 128;
+		len = LEN_512;
+		nbytes = 512;
 		break;
 
 	case FW_RSP_GET_UDI:

hw/application_fpga/fw/tk1/proto.h

@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2022 - Tillitis AB
+ * Copyright (C) 2022, 2023 - Tillitis AB
  * SPDX-License-Identifier: GPL-2.0-only
  */
 
@@ -19,10 +19,10 @@ enum cmdlen {
 	LEN_1,
 	LEN_4,
 	LEN_32,
-	LEN_128
+	LEN_512
 };
 
-#define CMDLEN_MAXBYTES 128
+#define CMDLEN_MAXBYTES 512
 
 // clang-format off
 enum fwcmd {