From 339ef8fb6a6ac81113e555d1b638cfdafaba851a Mon Sep 17 00:00:00 2001 From: Max Filippov Date: Thu, 21 Dec 2017 20:51:05 -0800 Subject: [PATCH] hw/xtensa/xtfpga: rewrite mini bootloader Don't load jump target into the CPU config, instead put it and initial a2 as literals into the mini bootloader and use l32r to load them natively. With these changes it should be possible to do warm reboot of the guest. Signed-off-by: Max Filippov --- hw/xtensa/xtfpga.c | 28 +++++++++++++++++++++++----- 1 file changed, 23 insertions(+), 5 deletions(-) diff --git a/hw/xtensa/xtfpga.c b/hw/xtensa/xtfpga.c index 1971ecfdc5..ba681683d6 100644 --- a/hw/xtensa/xtfpga.c +++ b/hw/xtensa/xtfpga.c @@ -372,15 +372,33 @@ static void lx_init(const LxBoardDesc *board, MachineState *machine) } } if (entry_point != env->pc) { - static const uint8_t jx_a0[] = { + uint8_t boot[] = { #ifdef TARGET_WORDS_BIGENDIAN - 0x0a, 0, 0, + 0x60, 0x00, 0x08, /* j 1f */ + 0x00, /* .literal_position */ + 0x00, 0x00, 0x00, 0x00, /* .literal entry_pc */ + 0x00, 0x00, 0x00, 0x00, /* .literal entry_a2 */ + /* 1: */ + 0x10, 0xff, 0xfe, /* l32r a0, entry_pc */ + 0x12, 0xff, 0xfe, /* l32r a2, entry_a2 */ + 0x0a, 0x00, 0x00, /* jx a0 */ #else - 0xa0, 0, 0, + 0x06, 0x02, 0x00, /* j 1f */ + 0x00, /* .literal_position */ + 0x00, 0x00, 0x00, 0x00, /* .literal entry_pc */ + 0x00, 0x00, 0x00, 0x00, /* .literal entry_a2 */ + /* 1: */ + 0x01, 0xfe, 0xff, /* l32r a0, entry_pc */ + 0x21, 0xfe, 0xff, /* l32r a2, entry_a2 */ + 0xa0, 0x00, 0x00, /* jx a0 */ #endif }; - env->regs[0] = entry_point; - cpu_physical_memory_write(env->pc, jx_a0, sizeof(jx_a0)); + uint32_t entry_pc = tswap32(entry_point); + uint32_t entry_a2 = tswap32(tagptr); + + memcpy(boot + 4, &entry_pc, sizeof(entry_pc)); + memcpy(boot + 8, &entry_a2, sizeof(entry_a2)); + cpu_physical_memory_write(env->pc, boot, sizeof(boot)); } } else { if (flash) {