atusb/fw/: added "HardMAC" support (not yet using the TRX's MAC)

- include/atusb/ep0.h (enum atspi_requests), ep0.c (my_setup): added
  new "HardMAC" requests ATUSB_RX_MODE and ATUSB_TX
- mac.h, mac.c: basic "HardMAC" procedure
- board_app.c (INT0_vect): call MAC-specific interrupt handler if
  provided
- Makefile (OBJS): added mac.o

atusb/fw/Makefile

@@ -31,7 +31,7 @@ SIZE = $(AVR_PREFIX)size
 USB_ID = 20b7:1540
 
 OBJS = atusb.o board.o board_app.o sernum.o spi.o descr.o ep0.o \
-       dfu_common.o usb.o app-atu2.o
+       dfu_common.o usb.o app-atu2.o mac.o
 BOOT_OBJS = boot.o board.o sernum.o spi.o flash.o dfu.o \
             dfu_common.o usb.o boot-atu2.o
 

atusb/fw/board_app.c

@@ -22,8 +22,9 @@
 
 #include "usb.h"
 #include "at86rf230.h"
-#include "board.h"
 #include "spi.h"
+#include "mac.h"
+#include "board.h"
 
 
 static volatile uint32_t timer_h = 0;	/* 2^(16+32) / 8 MHz = ~1.1 years */
@@ -155,6 +156,10 @@ uint8_t irq_serial;
 
 ISR(INT0_vect)
 {
+	if (mac_irq) {
+		mac_irq();
+		return;
+	}
 	if (eps[1].state == EP_IDLE) {
 		led(1);
 		irq_serial = (irq_serial+1) | 0x80;

atusb/fw/ep0.c

@@ -29,6 +29,7 @@
 #include "board.h"
 #include "sernum.h"
 #include "spi.h"
+#include "mac.h"
 
 
 #define	HW_TYPE		HW_TYPE_110131
@@ -239,6 +240,11 @@ static int my_setup(const struct setup_request *setup)
 		usb_send(&eps[0], buf, setup->wLength, NULL, NULL);
 		return 1;
 
+	case ATUSB_TO_DEV(ATUSB_RX_MODE):
+		return mac_rx(setup->wValue);
+	case ATUSB_TO_DEV(ATUSB_TX):
+		return mac_tx(setup->wValue, setup->wLength);
+
 	default:
 		error("Unrecognized SETUP: 0x%02x 0x%02x ...\n",
 		    setup->bmRequestType, setup->bRequest);

atusb/fw/include/atusb/ep0.h

@@ -39,7 +39,10 @@
  * host->	ATUSB_SPI_WRITE		byte0		byte1	#bytes
  * ->host	ATUSB_SPI_READ1		byte0		-	#bytes
  * ->host	ATUSB_SPI_READ2		byte0		byte1	#bytes
- * ->host	ATUSB_SPI_WRITE2_SYNC	byte0		bute1	0/1
+ * ->host	ATUSB_SPI_WRITE2_SYNC	byte0		byte1	0/1
+ *
+ * host->	ATUSB_RX_MODE		on		-	0
+ * host->	ATUSB_TX		flags		0	#bytes
  */
 
 /*
@@ -93,6 +96,8 @@ enum atspi_requests {
 	ATUSB_SPI_READ1,
 	ATUSB_SPI_READ2,
 	ATUSB_SPI_WRITE2_SYNC,
+	ATUSB_RX_MODE			= 0x40, /* HardMAC group */
+	ATUSB_TX,
 };
 
 

atusb/fw/mac.c

@@ -0,0 +1,154 @@
+/*
+ * fw/mac.c - HardMAC functions
+ *
+ * Written 2011 by Werner Almesberger
+ * Copyright 2011 Werner Almesberger
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <stddef.h>
+#include <stdint.h>
+
+#include "usb.h"
+
+#include "at86rf230.h"
+#include "spi.h"
+#include "mac.h"
+
+
+void (*mac_irq)(void) = NULL;
+
+
+static uint8_t rx_buf[MAX_PSDU+2]; /* PHDR+payload+LQ */
+static uint8_t tx_buf[MAX_PSDU];
+static uint8_t tx_size = 0;
+static int txing = 0;
+
+
+static uint8_t reg_read(uint8_t reg)
+{
+	uint8_t value;
+
+	spi_begin();
+	spi_send(AT86RF230_REG_READ | reg);
+	value= spi_recv();
+	spi_end();
+
+	return value;
+}
+
+
+static void reg_write(uint8_t reg, uint8_t value)
+{
+	spi_begin();
+	spi_send(AT86RF230_REG_WRITE | reg);
+	spi_send(value);
+	spi_end();
+}
+
+
+static void handle_irq(void)
+{
+	uint8_t irq;
+	uint8_t size, i;
+
+	irq = reg_read(REG_IRQ_STATUS);
+	if (!(irq & IRQ_TRX_END))
+		return;
+
+	/*
+	 * @@@ we probably also have to handle at least IRQ_PLL_UNLOCK, because
+	 * a PLL unlock should cause a transition out of BUSY_TX without
+	 * TRX_END.
+	 */
+	if (txing) {
+		txing = 0;
+		return;
+	}
+
+	/* unlikely */
+	if (eps[1].state != EP_IDLE)
+		return;
+
+	spi_begin();
+	spi_send(AT86RF230_BUF_READ);
+	size = spi_recv();
+	if (size & 0x80) {
+		spi_end();
+		return;
+	}
+
+	rx_buf[0] = size;
+	for (i = 0; i != size+1; i++)
+		rx_buf[i+1] = spi_recv();
+	spi_end();
+	usb_send(&eps[1], rx_buf, size+2, NULL, NULL);
+}
+
+
+int mac_rx(int on)
+{
+	if (on) {
+		mac_irq = handle_irq;
+		reg_read(REG_IRQ_STATUS);
+		reg_write(REG_TRX_STATE, TRX_CMD_RX_ON);
+	} else {
+		mac_irq = NULL;
+		reg_write(REG_TRX_STATE, TRX_CMD_FORCE_TRX_OFF);
+		txing = 0;
+	}
+	return 1;
+}
+
+
+static void do_tx(void *user)
+{
+	uint8_t status;
+	uint8_t i;
+
+	do status = reg_read(REG_TRX_STATUS) & TRX_STATUS_MASK;
+	while (status != TRX_STATUS_RX_ON && status != TRX_STATUS_RX_AACK_ON);
+
+	/*
+	 * We use TRX_CMD_FORCE_PLL_ON instead of TRX_CMD_PLL_ON because a new
+	 * reception may have begun while we were still working on the previous
+	 * one.
+	 */
+	reg_write(REG_TRX_STATE, TRX_CMD_FORCE_PLL_ON);
+
+	handle_irq();
+
+	spi_begin();
+	spi_send(AT86RF230_BUF_WRITE);
+	spi_send(tx_size);
+	for (i = 0; i != tx_size; i++)
+		spi_send(tx_buf[i]);
+	spi_end();
+
+	reg_write(REG_TRX_STATE, TRX_CMD_TX_START);
+
+	txing = 1;
+
+	/*
+	 * Wait until we reach BUSY_TX, so that we command the transition to
+	 * RX_ON which will be executed upon TX completion.
+	 */
+	while ((reg_read(REG_TRX_STATUS) & TRX_STATUS_MASK) ==
+	    TRX_STATUS_TRANSITION);
+	reg_write(REG_TRX_STATE, TRX_CMD_RX_ON);
+}
+
+
+int mac_tx(uint16_t flags, uint16_t len)
+{
+	if (len > MAX_PSDU)
+		return 0;
+	tx_size = len;
+	usb_recv(&eps[0], tx_buf, len, do_tx, NULL);
+	return 1;
+
+}

atusb/fw/mac.h

@@ -0,0 +1,24 @@
+/*
+ * fw/mac.h - HardMAC functions
+ *
+ * Written 2011 by Werner Almesberger
+ * Copyright 2011 Werner Almesberger
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#ifndef MAC_H
+#define	MAC_H
+
+#include <stdint.h>
+
+
+extern void (*mac_irq)(void);
+
+int mac_rx(int on);
+int mac_tx(uint16_t flags, uint16_t len);
+
+#endif /* !MAC_H */