new file mode 100644
@@ -0,0 +1,29 @@
+/*
+ * QEMU AVR CPU helpers
+ *
+ * Copyright (c) 2016-2020 Michael Rolnik
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see
+ * <http://www.gnu.org/licenses/lgpl-2.1.html>
+ */
+
+DEF_HELPER_1(wdr, void, env)
+DEF_HELPER_1(debug, void, env)
+DEF_HELPER_1(break, void, env)
+DEF_HELPER_1(sleep, void, env)
+DEF_HELPER_1(unsupported, void, env)
+DEF_HELPER_3(outb, void, env, i32, i32)
+DEF_HELPER_2(inb, tl, env, i32)
+DEF_HELPER_3(fullwr, void, env, i32, i32)
+DEF_HELPER_2(fullrd, tl, env, i32)
@@ -137,3 +137,206 @@ bool avr_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
return true;
}
+
+/*
+ * helpers
+ */
+
+void helper_sleep(CPUAVRState *env)
+{
+ CPUState *cs = env_cpu(env);
+
+ cs->exception_index = EXCP_HLT;
+ cpu_loop_exit(cs);
+}
+
+void helper_unsupported(CPUAVRState *env)
+{
+ CPUState *cs = env_cpu(env);
+
+ /*
+ * I count not find what happens on the real platform, so
+ * it's EXCP_DEBUG for meanwhile
+ */
+ cs->exception_index = EXCP_DEBUG;
+ if (qemu_loglevel_mask(LOG_UNIMP)) {
+ qemu_log("UNSUPPORTED\n");
+ cpu_dump_state(cs, stderr, 0);
+ }
+ cpu_loop_exit(cs);
+}
+
+void helper_debug(CPUAVRState *env)
+{
+ CPUState *cs = env_cpu(env);
+
+ cs->exception_index = EXCP_DEBUG;
+ cpu_loop_exit(cs);
+}
+
+void helper_break(CPUAVRState *env)
+{
+ CPUState *cs = env_cpu(env);
+
+ cs->exception_index = EXCP_DEBUG;
+ cpu_loop_exit(cs);
+}
+
+void helper_wdr(CPUAVRState *env)
+{
+ CPUState *cs = env_cpu(env);
+
+ /* WD is not implemented yet, placeholder */
+ cs->exception_index = EXCP_DEBUG;
+ cpu_loop_exit(cs);
+}
+
+/*
+ * This function implements IN instruction
+ *
+ * It does the following
+ * a. if an IO register belongs to CPU, its value is read and returned
+ * b. otherwise io address is translated to mem address and physical memory
+ * is read.
+ * c. it caches the value for sake of SBI, SBIC, SBIS & CBI implementation
+ *
+ */
+target_ulong helper_inb(CPUAVRState *env, uint32_t port)
+{
+ target_ulong data = 0;
+
+ switch (port) {
+ case 0x38: /* RAMPD */
+ data = 0xff & (env->rampD >> 16);
+ break;
+ case 0x39: /* RAMPX */
+ data = 0xff & (env->rampX >> 16);
+ break;
+ case 0x3a: /* RAMPY */
+ data = 0xff & (env->rampY >> 16);
+ break;
+ case 0x3b: /* RAMPZ */
+ data = 0xff & (env->rampZ >> 16);
+ break;
+ case 0x3c: /* EIND */
+ data = 0xff & (env->eind >> 16);
+ break;
+ case 0x3d: /* SPL */
+ data = env->sp & 0x00ff;
+ break;
+ case 0x3e: /* SPH */
+ data = env->sp >> 8;
+ break;
+ case 0x3f: /* SREG */
+ data = cpu_get_sreg(env);
+ break;
+ default:
+ /* not a special register, pass to normal memory access */
+ cpu_physical_memory_read(OFFSET_IO_REGISTERS + port, &data, 1);
+ }
+
+ return data;
+}
+
+/*
+ * This function implements OUT instruction
+ *
+ * It does the following
+ * a. if an IO register belongs to CPU, its value is written into the register
+ * b. otherwise io address is translated to mem address and physical memory
+ * is written.
+ * c. it caches the value for sake of SBI, SBIC, SBIS & CBI implementation
+ *
+ */
+void helper_outb(CPUAVRState *env, uint32_t port, uint32_t data)
+{
+ data &= 0x000000ff;
+
+ switch (port) {
+ case 0x38: /* RAMPD */
+ if (avr_feature(env, AVR_FEATURE_RAMPD)) {
+ env->rampD = (data & 0xff) << 16;
+ }
+ break;
+ case 0x39: /* RAMPX */
+ if (avr_feature(env, AVR_FEATURE_RAMPX)) {
+ env->rampX = (data & 0xff) << 16;
+ }
+ break;
+ case 0x3a: /* RAMPY */
+ if (avr_feature(env, AVR_FEATURE_RAMPY)) {
+ env->rampY = (data & 0xff) << 16;
+ }
+ break;
+ case 0x3b: /* RAMPZ */
+ if (avr_feature(env, AVR_FEATURE_RAMPZ)) {
+ env->rampZ = (data & 0xff) << 16;
+ }
+ break;
+ case 0x3c: /* EIDN */
+ env->eind = (data & 0xff) << 16;
+ break;
+ case 0x3d: /* SPL */
+ env->sp = (env->sp & 0xff00) | (data);
+ break;
+ case 0x3e: /* SPH */
+ if (avr_feature(env, AVR_FEATURE_2_BYTE_SP)) {
+ env->sp = (env->sp & 0x00ff) | (data << 8);
+ }
+ break;
+ case 0x3f: /* SREG */
+ cpu_set_sreg(env, data);
+ break;
+ default:
+ /* not a special register, pass to normal memory access */
+ cpu_physical_memory_write(OFFSET_IO_REGISTERS + port, &data, 1);
+ }
+}
+
+/*
+ * this function implements LD instruction when there is a posibility to read
+ * from a CPU register
+ */
+target_ulong helper_fullrd(CPUAVRState *env, uint32_t addr)
+{
+ uint8_t data;
+
+ env->fullacc = false;
+
+ if (addr < NUMBER_OF_CPU_REGISTERS) {
+ /* CPU registers */
+ data = env->r[addr];
+ } else if (addr < NUMBER_OF_CPU_REGISTERS + NUMBER_OF_IO_REGISTERS) {
+ /* IO registers */
+ data = helper_inb(env, addr - NUMBER_OF_CPU_REGISTERS);
+ } else {
+ /* memory */
+ cpu_physical_memory_read(OFFSET_DATA + addr, &data, 1);
+ }
+ return data;
+}
+
+/*
+ * this function implements ST instruction when there is a posibility to write
+ * into a CPU register
+ */
+void helper_fullwr(CPUAVRState *env, uint32_t data, uint32_t addr)
+{
+ env->fullacc = false;
+
+ /* Following logic assumes this: */
+ assert(OFFSET_CPU_REGISTERS == OFFSET_DATA);
+ assert(OFFSET_IO_REGISTERS == OFFSET_CPU_REGISTERS +
+ NUMBER_OF_CPU_REGISTERS);
+
+ if (addr < NUMBER_OF_CPU_REGISTERS) {
+ /* CPU registers */
+ env->r[addr] = data;
+ } else if (addr < NUMBER_OF_CPU_REGISTERS + NUMBER_OF_IO_REGISTERS) {
+ /* IO registers */
+ helper_outb(env, addr - NUMBER_OF_CPU_REGISTERS, data);
+ } else {
+ /* memory */
+ cpu_physical_memory_write(OFFSET_DATA + addr, &data, 1);
+ }
+}