ar100: Support for ar100 (#6054)

Add files to support AR100

Signed-off-by: Elias Bakken <elias@iagent.no>

1 files changed, 102 insertions, 0 deletions

diff --git a/scripts/flash-ar100.py b/scripts/flash-ar100.py
new file mode 100755
index 00000000..33198e23
--- /dev/null
+++ b/scripts/flash-ar100.py
@@ -0,0 +1,102 @@
+#!/usr/bin/env python3
+# This file may be distributed under the terms of the GNU GPLv3 license.
+import mmap
+import argparse
+import sys
+
+FW_START = 0x00004000
+FW_BASE = 0x00040000 + FW_START
+FW_LIMIT = 0x00054000
+FW_SIZE = FW_LIMIT - FW_BASE
+
+EXCEPTIONS_BASE = 0x00040000
+EXCEPTIONS_LIMIT = 0x00042000
+EXCEPTIONS_SIZE = EXCEPTIONS_LIMIT - EXCEPTIONS_BASE
+EXCEPTIONS_JUMP = FW_START  # All exceptions reset program
+NR_OF_EXCEPTIONS = 14
+
+R_CPU_CFG_PAGE_BASE = 0x01F01000
+R_CPU_CFG_PAGE_LIMIT = 0x01F02000
+R_CPU_CFG_SIZE = R_CPU_CFG_PAGE_LIMIT - R_CPU_CFG_PAGE_BASE
+R_CPU_CFG_OFFSET = 0xC00
+R_CPU_CLK_OFFSET = 0x400
+
+parser = argparse.ArgumentParser(description='Flash and reset SRAM A2 of A64')
+parser.add_argument('filename', nargs='?', help='binary file to write')
+parser.add_argument('--reset', action='store_true', help='reset the AR100')
+parser.add_argument('--halt', action='store_true', help='Halt the AR100')
+parser.add_argument('--bl31', action='store_true', help='write bl31')
+
+args = parser.parse_args()
+
+
+def write_exception_vectors():
+    print("Writing exception vectors")
+    with open("/dev/mem", "w+b") as f:
+        exc = mmap.mmap(f.fileno(),
+                        length=EXCEPTIONS_SIZE,
+                        offset=EXCEPTIONS_BASE)
+        for i in range(NR_OF_EXCEPTIONS):
+            add = i * 0x100
+            exc[add:add + 4] = ((EXCEPTIONS_JUMP - add) >> 2).to_bytes(
+                4, byteorder='little')
+        exc.close()
+
+
+def assert_deassert_reset(ass):
+    with open("/dev/mem", "w+b") as f:
+        r_cpucfg = mmap.mmap(f.fileno(),
+                             length=R_CPU_CFG_SIZE,
+                             offset=R_CPU_CFG_PAGE_BASE)
+        if ass:
+            r_cpucfg[R_CPU_CFG_OFFSET] &= ~0x01
+            if r_cpucfg[R_CPU_CFG_OFFSET] & 0x01:
+                print("failed to assert reset")
+        else:
+            r_cpucfg[R_CPU_CFG_OFFSET] |= 0x01
+            if not (r_cpucfg[R_CPU_CFG_OFFSET] & 0x01):
+                print("failed to deassert reset")
+        r_cpucfg.close()
+
+
+def write_file(filename):
+    with open(filename, "r+b") as fw:
+        data = fw.read()
+        if len(data) > FW_SIZE:
+            print("File does not fit in memory")
+            sys.exit(1)
+        print("Writing file to SRAM A2")
+        with open("/dev/mem", "w+b") as f:
+            sram_a2 = mmap.mmap(f.fileno(), length=FW_SIZE, offset=FW_BASE)
+            sram_a2[0:len(data)] = data
+            sram_a2.close()
+
+
+def clear_magic_word():
+    with open("/dev/mem", "w+b") as f:
+        sram_a2 = mmap.mmap(f.fileno(), length=FW_SIZE, offset=FW_BASE)
+        sram_a2[0] = 0x0
+        sram_a2.close()
+
+
+if args.reset:
+    print("Resetting AR100")
+    assert_deassert_reset(1)
+    assert_deassert_reset(0)
+    sys.exit(0)
+
+if args.filename:
+    if args.bl31:
+        print("writing bl31")
+        assert_deassert_reset(1)
+        write_file(args.filename)
+    else:
+        assert_deassert_reset(1)
+        write_exception_vectors()
+        write_file(args.filename)
+        assert_deassert_reset(0)
+
+if args.halt:
+    print("Halting AR100")
+    assert_deassert_reset(1)
+    clear_magic_word()