X-Git-Url: https://jxself.org/git/?a=blobdiff_plain;f=atusb%2Fmac.c;fp=atusb%2Fmac.c;h=835002c362c9219eb9ae8f381a11afbcb1419fae;hb=dd4bc9ff49b9a7075e579fdd62fd930d27a9a7df;hp=0000000000000000000000000000000000000000;hpb=c164bf7f87f9081fee7e1a186dd7a87a9a020b9e;p=linux-libre-firmware.git

diff --git a/atusb/mac.c b/atusb/mac.c
new file mode 100644
index 0000000..835002c
--- /dev/null
+++ b/atusb/mac.c
@@ -0,0 +1,250 @@
+/*
+ * fw/mac.c - HardMAC functions
+ *
+ * Written 2011, 2013 by Werner Almesberger
+ * Copyright 2011, 2013 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 <stdbool.h>
+#include <stdint.h>
+
+#include "usb.h"
+
+#include "at86rf230.h"
+#include "spi.h"
+#include "board.h"
+#include "mac.h"
+
+#define	RX_BUFS	3
+
+
+bool (*mac_irq)(void) = NULL;
+
+
+static uint8_t rx_buf[RX_BUFS][MAX_PSDU+2]; /* PHDR+payload+LQ */
+static uint8_t tx_buf[MAX_PSDU];
+static uint8_t tx_size = 0;
+static bool txing = 0;
+static bool queued_tx_ack = 0;
+static uint8_t next_seq, this_seq, queued_seq;
+
+
+/* ----- Receive buffer management ----------------------------------------- */
+
+
+static uint8_t rx_in = 0, rx_out = 0;
+
+
+static inline void next_buf(uint8_t *index)
+{
+	*index = (*index+1) % RX_BUFS;
+}
+
+
+/* ----- Interrupt handling ------------------------------------------------ */
+
+
+static void rx_done(void *user);
+static void tx_ack_done(void *user);
+
+
+static void usb_next(void)
+{
+	const uint8_t *buf;
+
+	if (rx_in != rx_out) {
+		buf = rx_buf[rx_out];
+		led(1);
+		usb_send(&eps[1], buf, buf[0]+2, rx_done, NULL);
+	}
+
+	if (queued_tx_ack) {
+		usb_send(&eps[1], &queued_seq, 1, tx_ack_done, NULL);
+		queued_tx_ack = 0;	
+	}
+}
+
+
+static void tx_ack_done(void *user)
+{
+	usb_next();
+}
+
+static void rx_done(void *user)
+{
+	led(0);
+	next_buf(&rx_out);
+	usb_next();
+#ifdef AT86RF230
+	/* slap at86rf230 - reduce fragmentation issue */
+	change_state(TRX_STATUS_RX_AACK_ON);
+#endif
+}
+
+
+static void receive_frame(void)
+{
+	uint8_t size;
+	uint8_t *buf;
+
+	spi_begin();
+	spi_io(AT86RF230_BUF_READ);
+
+	size = spi_recv();
+	if (!size || (size & 0x80)) {
+		spi_end();
+		return;
+	}
+
+	buf = rx_buf[rx_in];
+	spi_recv_block(buf+1, size+1);
+	spi_end();
+
+	buf[0] = size;
+	next_buf(&rx_in);
+
+	if (eps[1].state == EP_IDLE)
+		usb_next();
+}
+
+
+static bool handle_irq(void)
+{
+	uint8_t irq;
+
+	irq = reg_read(REG_IRQ_STATUS);
+	if (!(irq & IRQ_TRX_END))
+		return 1;
+
+	if (txing) {
+		if (eps[1].state == EP_IDLE) {
+			usb_send(&eps[1], &this_seq, 1, tx_ack_done, NULL);
+		} else {
+			queued_tx_ack = 1;
+			queued_seq = this_seq;
+		}
+		txing = 0;
+		return 1;
+	}
+
+	/* likely */
+	if (eps[1].state == EP_IDLE || rx_in != rx_out)
+		receive_frame();
+
+	return 1;
+}
+
+
+/* ----- TX/RX ------------------------------------------------------------- */
+
+
+bool mac_rx(int on)
+{
+	if (on) {
+		mac_irq = handle_irq;
+		reg_read(REG_IRQ_STATUS);
+		change_state(TRX_CMD_RX_AACK_ON);
+	} else {
+		mac_irq = NULL;
+		change_state(TRX_CMD_FORCE_TRX_OFF);
+		txing = 0;
+	}
+	return 1;
+}
+
+
+static void do_tx(void *user)
+{
+	uint16_t timeout = 0xffff;
+	uint8_t status;
+	uint8_t i;
+
+	/*
+	 * If we time out here, the host driver will time out waiting for the
+	 * TRX_END acknowledgement.
+	 */
+	do {
+		if (!--timeout)
+			return;
+		status = reg_read(REG_TRX_STATUS) & TRX_STATUS_MASK;
+	}
+	while (status != TRX_STATUS_RX_ON && status != TRX_STATUS_RX_AACK_ON);
+
+#ifdef AT86RF231
+	/*
+	 * 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);
+#endif
+#ifdef AT86RF230
+	/*
+	 * at86rf230 doesn't support force change, nevetherless this works
+	 * somehow
+	 */
+	reg_write(REG_TRX_STATE, TRX_CMD_PLL_ON);
+#endif
+#ifdef AT86RF212
+	/*
+	* 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);
+#endif
+
+	handle_irq();
+
+	spi_begin();
+	spi_send(AT86RF230_BUF_WRITE);
+	spi_send(tx_size+2); /* CRC */
+	for (i = 0; i != tx_size; i++)
+		spi_send(tx_buf[i]);
+	spi_end();
+
+	change_state(TRX_STATUS_TX_ARET_ON);
+
+	slp_tr();
+
+	txing = 1;
+	this_seq = next_seq;
+
+	/*
+	 * Wait until we reach BUSY_TX_ARET, so that we command the transition to
+	 * RX_AACK_ON which will be executed upon TX completion.
+	 */
+	change_state(TRX_CMD_PLL_ON);
+	change_state(TRX_CMD_RX_AACK_ON);
+}
+
+
+bool mac_tx(uint16_t flags, uint8_t seq, uint16_t len)
+{
+	if (len > MAX_PSDU)
+		return 0;
+	tx_size = len;
+	next_seq = seq;
+	usb_recv(&eps[0], tx_buf, len, do_tx, NULL);
+	return 1;
+}
+
+
+void mac_reset(void)
+{
+	mac_irq = NULL;
+	txing = 0;
+	queued_tx_ack = 0;
+	rx_in = rx_out = 0;
+	next_seq = this_seq = queued_seq = 0;
+
+	/* enable CRC and PHY_RSSI (with RX_CRC_VALID) in SPI status return */
+	reg_write(REG_TRX_CTRL_1,
+	    TX_AUTO_CRC_ON | SPI_CMD_MODE_PHY_RSSI << SPI_CMD_MODE_SHIFT);
+}