8bit AVR port from Michael Rolnik.

Michael started to work on the AVR port few years ago [*] and kept
 improving the code over various series.
 
 List of people who help him (in chronological order):
 - Richard Henderson
 - Sarah Harris and Edward Robbins
 - Philippe Mathieu-Daudé and Aleksandar Markovic
 - Pavel Dovgalyuk
 - Thomas Huth
 
 [*] The oldest contribution I could find on the list is from 2016:
 https://lists.nongnu.org/archive/html/qemu-devel/2016-06/msg02985.html
 
 Tests included:
 
 $ avocado --show=app run -t arch:avr tests/acceptance/
 Fetching asset from tests/acceptance/machine_avr6.py:AVR6Machine.test_freertos
  (1/1) tests/acceptance/machine_avr6.py:AVR6Machine.test_freertos: PASS (2.13 s)
 RESULTS    : PASS 1 | ERROR 0 | FAIL 0 | SKIP 0 | WARN 0 | INTERRUPT 0 | CANCEL 0
 JOB TIME   : 2.35 s
 
 $ make check-qtest-avr
   TEST    check-qtest-avr: tests/qtest/boot-serial-test
   TEST    check-qtest-avr: tests/qtest/cdrom-test
   TEST    check-qtest-avr: tests/qtest/device-introspect-test
   TEST    check-qtest-avr: tests/qtest/machine-none-test
   TEST    check-qtest-avr: tests/qtest/qmp-test
   TEST    check-qtest-avr: tests/qtest/qmp-cmd-test
   TEST    check-qtest-avr: tests/qtest/qom-test
   TEST    check-qtest-avr: tests/qtest/test-hmp
   TEST    check-qtest-avr: tests/qtest/qos-test
 
 CI results:
 . https://cirrus-ci.com/build/5697049146425344
 . 165328058
 . 705817933
 . https://app.shippable.com/github/philmd/qemu/runs/822/summary/console
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Merge remote-tracking branch 'remotes/philmd-gitlab/tags/avr-port-20200711' into staging

8bit AVR port from Michael Rolnik.

Michael started to work on the AVR port few years ago [*] and kept
improving the code over various series.

List of people who help him (in chronological order):
- Richard Henderson
- Sarah Harris and Edward Robbins
- Philippe Mathieu-Daudé and Aleksandar Markovic
- Pavel Dovgalyuk
- Thomas Huth

[*] The oldest contribution I could find on the list is from 2016:
https://lists.nongnu.org/archive/html/qemu-devel/2016-06/msg02985.html

Tests included:

$ avocado --show=app run -t arch:avr tests/acceptance/
Fetching asset from tests/acceptance/machine_avr6.py:AVR6Machine.test_freertos
 (1/1) tests/acceptance/machine_avr6.py:AVR6Machine.test_freertos: PASS (2.13 s)
RESULTS    : PASS 1 | ERROR 0 | FAIL 0 | SKIP 0 | WARN 0 | INTERRUPT 0 | CANCEL 0
JOB TIME   : 2.35 s

$ make check-qtest-avr
  TEST    check-qtest-avr: tests/qtest/boot-serial-test
  TEST    check-qtest-avr: tests/qtest/cdrom-test
  TEST    check-qtest-avr: tests/qtest/device-introspect-test
  TEST    check-qtest-avr: tests/qtest/machine-none-test
  TEST    check-qtest-avr: tests/qtest/qmp-test
  TEST    check-qtest-avr: tests/qtest/qmp-cmd-test
  TEST    check-qtest-avr: tests/qtest/qom-test
  TEST    check-qtest-avr: tests/qtest/test-hmp
  TEST    check-qtest-avr: tests/qtest/qos-test

CI results:
. https://cirrus-ci.com/build/5697049146425344
. 165328058
. 705817933
. https://app.shippable.com/github/philmd/qemu/runs/822/summary/console

# gpg: Signature made Sat 11 Jul 2020 10:03:11 BST
# gpg:                using RSA key FAABE75E12917221DCFD6BB2E3E32C2CDEADC0DE
# gpg: Good signature from "Philippe Mathieu-Daudé (F4BUG) <f4bug@amsat.org>" [full]
# Primary key fingerprint: FAAB E75E 1291 7221 DCFD  6BB2 E3E3 2C2C DEAD C0DE

* remotes/philmd-gitlab/tags/avr-port-20200711: (32 commits)
  target/avr/disas: Fix store instructions display order
  target/avr/cpu: Fix $PC displayed address
  target/avr/cpu: Drop tlb_flush() in avr_cpu_reset()
  target/avr: Add section into QEMU documentation
  tests/acceptance: Test the Arduino MEGA2560 board
  tests/boot-serial: Test some Arduino boards (AVR based)
  hw/avr: Add limited support for some Arduino boards
  hw/avr: Add some ATmega microcontrollers
  hw/avr: Add support for loading ELF/raw binaries
  hw/misc: avr: Add limited support for power reduction device
  hw/timer: avr: Add limited support for 16-bit timer peripheral
  hw/char: avr: Add limited support for USART peripheral
  tests/machine-none: Add AVR support
  target/avr: Register AVR support with the rest of QEMU
  target/avr: Add support for disassembling via option '-d in_asm'
  target/avr: Initialize TCG register variables
  target/avr: Add instruction translation - CPU main translation function
  target/avr: Add instruction translation - MCU Control Instructions
  target/avr: Add instruction translation - Bit and Bit-test Instructions
  target/avr: Add instruction translation - Data Transfer Instructions
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

tests/qtest/Makefile.include

@@ -66,6 +66,8 @@ check-qtest-i386-y += numa-test
 
 check-qtest-x86_64-y += $(check-qtest-i386-y)
 
+check-qtest-avr-y += boot-serial-test
+
 check-qtest-alpha-y += boot-serial-test
 check-qtest-alpha-$(CONFIG_VGA) += display-vga-test
 

tests/qtest/boot-serial-test.c

@@ -17,6 +17,15 @@
 #include "libqtest.h"
 #include "libqos/libqos-spapr.h"
 
+static const uint8_t bios_avr[] = {
+    0x88, 0xe0,             /* ldi r24, 0x08   */
+    0x80, 0x93, 0xc1, 0x00, /* sts 0x00C1, r24 ; Enable tx */
+    0x86, 0xe0,             /* ldi r24, 0x06   */
+    0x80, 0x93, 0xc2, 0x00, /* sts 0x00C2, r24 ; Set the data bits to 8 */
+    0x84, 0xe5,             /* ldi r24, 0x54   */
+    0x80, 0x93, 0xc6, 0x00, /* sts 0x00C6, r24 ; Output 'T' */
+};
+
 static const uint8_t kernel_mcf5208[] = {
     0x41, 0xf9, 0xfc, 0x06, 0x00, 0x00,     /* lea 0xfc060000,%a0 */
     0x10, 0x3c, 0x00, 0x54,                 /* move.b #'T',%d0 */
@@ -104,6 +113,8 @@ typedef struct testdef {
 
 static testdef_t tests[] = {
     { "alpha", "clipper", "", "PCI:" },
+    { "avr", "arduino-duemilanove", "", "T", sizeof(bios_avr), NULL, bios_avr },
+    { "avr", "arduino-mega-2560-v3", "", "T", sizeof(bios_avr), NULL, bios_avr},
     { "ppc", "ppce500", "", "U-Boot" },
     { "ppc", "40p", "-vga none -boot d", "Trying cd:," },
     { "ppc", "g3beige", "", "PowerPC,750" },

tests/qtest/machine-none-test.c

@@ -27,6 +27,7 @@ static struct arch2cpu cpus_map[] = {
     /* tested targets list */
     { "arm", "cortex-a15" },
     { "aarch64", "cortex-a57" },
+    { "avr", "avr6-avr-cpu" },
     { "x86_64", "qemu64,apic-id=0" },
     { "i386", "qemu32,apic-id=0" },
     { "alpha", "ev67" },