1 files changed, 202 insertions, 0 deletions
diff --git a/firmware/zpu/usrp2p/bootloader/fpga_bootloader.c b/firmware/zpu/usrp2p/bootloader/fpga_bootloader.c
new file mode 100644
index 000000000..f5a71a8bb
--- /dev/null
+++ b/firmware/zpu/usrp2p/bootloader/fpga_bootloader.c
@@ -0,0 +1,202 @@
+/* -*- c -*- */
+/*
+ * Copyright 2009-2011 Ettus Research LLC
+ *
+ * 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/*
+ * This code is bootloader f/w for the slot 0 fpga image.  It's job is
+ * to figure out which fpga image should be loaded, and then to load
+ * that image from the SPI flash.  (FIXME handle retries, errors,
+ * etc.)
+ *
+ * If the center button is down during boot, it loads firwmare
+ * from 0:0 instead of its normal action.
+ */
+
+#include <stdlib.h>
+#include <hal_io.h>
+#include <nonstdio.h>
+#include <mdelay.h>
+#include <quadradio/flashdir.h>
+#include <xilinx_v5_icap.h>
+#include <bootconfig.h>
+#include <bootconfig_private.h>
+#include <spi_flash.h>
+#include <string.h>
+#include <bootloader_utils.h>
+#include <hal_interrupts.h>
+
+#define VERBOSE 1
+
+#define	OUR_FPGA_IMAGE_NUMBER	0	// this code only runs in slot 0
+
+void hal_uart_init(void);
+void spif_init(void);
+void i2c_init(void);
+void bootconfig_init(void);
+
+void pic_interrupt_handler() __attribute__ ((interrupt_handler));
+
+void pic_interrupt_handler()
+{
+  // nop stub
+}
+
+static int
+flash_addr_of_fpga_slot(unsigned int fpga_slot)
+{
+  const struct flashdir *fd = get_flashdir();
+  return fd->slot[fpga_slot + fd->fpga_slot0].start << spi_flash_log2_sector_size();
+}
+
+
+/*
+ * If the first 256 bytes of the image contain the string of bytes,
+ * ff ff ff ff aa 99 55 66, we consider it a likely bitstream.
+ */
+static bool
+looks_like_a_bitstream(unsigned int fpga_slot)
+{
+  unsigned char buf[256];
+  static const unsigned char pattern[] = {
+    0xff, 0xff, 0xff, 0xff, 0xaa, 0x99, 0x55, 0x66
+  };
+
+  // Read the first 256 bytes of the bitstream
+  spi_flash_read(flash_addr_of_fpga_slot(fpga_slot), sizeof(buf), buf);
+
+  for (int i = 0; i <= sizeof(buf) - sizeof(pattern); i++)
+    if (memcmp(pattern, &buf[i], sizeof(pattern)) == 0)
+      return true;
+
+  return false;
+}
+
+static bool
+plausible_bootconfig(bootconfig_t bc)
+{
+  // Are the fields in range?
+  if (!validate_bootconfig(bc))
+    return false;
+
+  if (!looks_like_a_bitstream(map_fpga_image_number_to_fpga_slot(bc.fpga_image_number)))
+    return false;
+
+  return true;
+}
+
+// Attempt to boot the fpga image specified in next_boot
+static void
+initial_boot_attempt(eeprom_boot_info_t *ee)
+{
+  if (ee->next_boot.fpga_image_number == OUR_FPGA_IMAGE_NUMBER){
+    load_firmware();
+    return;
+  }
+
+  ee->nattempts = 1;
+  _bc_write_eeprom_shadow();
+
+  unsigned int target_slot =
+    map_fpga_image_number_to_fpga_slot(ee->next_boot.fpga_image_number);
+  int flash_addr = flash_addr_of_fpga_slot(target_slot);
+
+  putstr("fpga_bootloader: chaining to ");
+  puthex4(ee->next_boot.fpga_image_number);
+  putchar(':');
+  puthex4(ee->next_boot.firmware_image_number);
+  newline();
+  mdelay(100);
+
+  while (1){
+    icap_reload_fpga(flash_addr);
+  }
+}
+
+int
+main(int argc, char **argv)
+{
+  hal_disable_ints();	// In case we got here via jmp 0x0
+  hal_uart_init();
+  i2c_init();
+  bootconfig_init();	// Must come after i2c_init.
+  spif_init();		// Needed for get_flashdir.
+
+  sr_leds->leds =  0xAAAA;
+
+  putstr("\n\n>>> fpga_bootloader <<<\n");
+
+  putstr("\nBOOTSTS ");
+  int bootsts = icap_read_config_reg(rBOOTSTS);
+  puthex32_nl(bootsts);
+  putstr("STAT    ");
+  int stat = icap_read_config_reg(rSTAT);
+  puthex32_nl(stat);
+
+  bool fallback =
+    ((bootsts & (BOOTSTS_VALID_0 | BOOTSTS_FALLBACK_0))
+     == (BOOTSTS_VALID_0 | BOOTSTS_FALLBACK_0));
+
+  if (fallback){
+    puts("FALLBACK_0 is set");
+    // FIXME handle fallback condition.
+  }
+
+  const struct flashdir *fd = get_flashdir();
+  if (fd == 0)
+    abort();
+
+  eeprom_boot_info_t *ee = _bc_get_eeprom_shadow();
+
+  if (VERBOSE){
+    putstr("nattempts: ");
+    puthex8_nl(ee->nattempts);
+  }
+
+  mdelay(500);	// wait for low-pass on switches
+  putstr("switches: "); puthex32_nl(readback->switches);
+
+  bool center_btn_down = (readback->switches & BTN_CENTER) != 0;
+  if (center_btn_down){
+    putstr("Center button is down!\n");
+    // Force boot of image 0:0
+    ee->next_boot = make_bootconfig(0, 0);
+  }
+
+  // if next_boot is valid, try it
+  if (plausible_bootconfig(ee->next_boot))
+    initial_boot_attempt(ee);	// no return
+
+  // if default_boot is valid, try it
+  if (plausible_bootconfig(ee->default_boot)){
+    ee->next_boot = ee->default_boot;
+    initial_boot_attempt(ee);	// no return
+  }
+
+  // If we're here, we're in trouble.  Try all of them...
+  for (int i = 0; i < 4; i++){
+    bootconfig_t bc = make_bootconfig(i, 0);
+    if (plausible_bootconfig(bc)){
+      ee->next_boot = bc;
+      initial_boot_attempt(ee);	// no return
+    }
+  }
+
+  // FIXME, try to find something we can load
+  puts("\n!!! Failed to find a valid FPGA bitstream!\n\n");
+
+  return 0;
+}