Integrate the i/o 0x00-0x1f and 0x38-0x3f loopbacks into
the cpu registers with normal address space accesses.
We no longer need to trap accesses to the first page within
avr_cpu_tlb_fill but can wait until a write occurs.
Signed-off-by: Richard Henderson <richard.hender...@linaro.org>
---
target/avr/cpu.h | 7 ++
target/avr/helper.h | 3 -
target/avr/cpu.c | 16 +++
target/avr/helper.c | 223 +++++++++++++++++------------------------
target/avr/translate.c | 42 ++++----
5 files changed, 138 insertions(+), 153 deletions(-)
diff --git a/target/avr/cpu.h b/target/avr/cpu.h
index ebcdda20ac..9862705c6a 100644
--- a/target/avr/cpu.h
+++ b/target/avr/cpu.h
@@ -23,6 +23,7 @@
#include "cpu-qom.h"
#include "exec/cpu-defs.h"
+#include "exec/memory.h"
#ifdef CONFIG_USER_ONLY
#error "AVR 8-bit does not support user mode"
@@ -150,6 +151,9 @@ struct ArchCPU {
CPUAVRState env;
+ MemoryRegion cpu_reg1;
+ MemoryRegion cpu_reg2;
+
/* Initial value of stack pointer */
uint32_t init_sp;
};
@@ -250,6 +254,9 @@ bool avr_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
MMUAccessType access_type, int mmu_idx,
bool probe, uintptr_t retaddr);
+extern const MemoryRegionOps avr_cpu_reg1;
+extern const MemoryRegionOps avr_cpu_reg2;
+
#include "exec/cpu-all.h"
#endif /* QEMU_AVR_CPU_H */
diff --git a/target/avr/helper.h b/target/avr/helper.h
index 4d02e648fa..e8d13e925f 100644
--- a/target/avr/helper.h
+++ b/target/avr/helper.h
@@ -23,7 +23,4 @@ DEF_HELPER_1(debug, noreturn, env)
DEF_HELPER_1(break, noreturn, env)
DEF_HELPER_1(sleep, noreturn, env)
DEF_HELPER_1(unsupported, noreturn, 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)
diff --git a/target/avr/cpu.c b/target/avr/cpu.c
index 834c7082aa..0b14b36c17 100644
--- a/target/avr/cpu.c
+++ b/target/avr/cpu.c
@@ -23,6 +23,7 @@
#include "qemu/qemu-print.h"
#include "exec/exec-all.h"
#include "exec/translation-block.h"
+#include "exec/address-spaces.h"
#include "cpu.h"
#include "disas/dis-asm.h"
#include "tcg/debug-assert.h"
@@ -110,6 +111,8 @@ static void avr_cpu_disas_set_info(CPUState *cpu,
disassemble_info *info)
static void avr_cpu_realizefn(DeviceState *dev, Error **errp)
{
CPUState *cs = CPU(dev);
+ CPUAVRState *env = cpu_env(cs);
+ AVRCPU *cpu = env_archcpu(env);
AVRCPUClass *mcc = AVR_CPU_GET_CLASS(dev);
Error *local_err = NULL;
@@ -122,6 +125,19 @@ static void avr_cpu_realizefn(DeviceState *dev, Error
**errp)
cpu_reset(cs);
mcc->parent_realize(dev, errp);
+
+ /*
+ * Two blocks in the low data space loop back into cpu registers.
+ */
+ memory_region_init_io(&cpu->cpu_reg1, OBJECT(cpu), &avr_cpu_reg1, env,
+ "avr-cpu-reg1", 32);
+ memory_region_add_subregion(get_system_memory(),
+ OFFSET_DATA, &cpu->cpu_reg1);
+
+ memory_region_init_io(&cpu->cpu_reg2, OBJECT(cpu), &avr_cpu_reg2, env,
+ "avr-cpu-reg2", 8);
+ memory_region_add_subregion(get_system_memory(),
+ OFFSET_DATA + 0x58, &cpu->cpu_reg2);
}
static void avr_cpu_set_int(void *opaque, int irq, int level)
diff --git a/target/avr/helper.c b/target/avr/helper.c
index f8ada8b106..d0e86f5614 100644
--- a/target/avr/helper.c
+++ b/target/avr/helper.c
@@ -108,7 +108,7 @@ bool avr_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
MMUAccessType access_type, int mmu_idx,
bool probe, uintptr_t retaddr)
{
- int prot, page_size = TARGET_PAGE_SIZE;
+ int prot;
uint32_t paddr;
address &= TARGET_PAGE_MASK;
@@ -133,23 +133,9 @@ bool avr_cpu_tlb_fill(CPUState *cs, vaddr address, int
size,
/* Access to memory. */
paddr = OFFSET_DATA + address;
prot = PAGE_READ | PAGE_WRITE;
- if (address < NUMBER_OF_CPU_REGISTERS + NUMBER_OF_IO_REGISTERS) {
- /*
- * Access to CPU registers, exit and rebuilt this TB to use
- * full access in case it touches specially handled registers
- * like SREG or SP. For probing, set page_size = 1, in order
- * to force tlb_fill to be called for the next access.
- */
- if (probe) {
- page_size = 1;
- } else {
- cpu_env(cs)->fullacc = 1;
- cpu_loop_exit_restore(cs, retaddr);
- }
- }
}
- tlb_set_page(cs, address, paddr, prot, mmu_idx, page_size);
+ tlb_set_page(cs, address, paddr, prot, mmu_idx, TARGET_PAGE_SIZE);
return true;
}
@@ -203,134 +189,78 @@ void helper_wdr(CPUAVRState *env)
}
/*
- * 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
- *
+ * The first 32 bytes of the data space are mapped to the cpu regs.
+ * We cannot write these from normal store operations because TCG
+ * does not expect global temps to be modified -- a global may be
+ * live in a host cpu register across the store. We can however
+ * read these, as TCG does make sure the global temps are saved
+ * in case the load operation traps.
*/
-target_ulong helper_inb(CPUAVRState *env, uint32_t port)
+
+static uint64_t avr_cpu_reg1_read(void *opaque, hwaddr addr, unsigned size)
{
- target_ulong data = 0;
+ CPUAVRState *env = opaque;
- switch (port - 0x38) {
- case REG_38_RAMPD:
- data = 0xff & (env->rampD >> 16);
- break;
- case REG_38_RAMPX:
- data = 0xff & (env->rampX >> 16);
- break;
- case REG_38_RAMPY:
- data = 0xff & (env->rampY >> 16);
- break;
- case REG_38_RAMPZ:
- data = 0xff & (env->rampZ >> 16);
- break;
- case REG_38_EIDN:
- data = 0xff & (env->eind >> 16);
- break;
- case REG_38_SPL:
- data = env->sp & 0x00ff;
- break;
- case REG_38_SPH:
- data = env->sp >> 8;
- break;
- case REG_38_SREG:
- data = cpu_get_sreg(env);
- break;
- default:
- /* not a special register, pass to normal memory access */
- data = address_space_ldub(&address_space_memory,
- OFFSET_IO_REGISTERS + port,
- MEMTXATTRS_UNSPECIFIED, NULL);
- }
-
- return data;
+ assert(addr < 32);
+ return env->r[addr];
}
/*
- * 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
- *
+ * The range 0x38-0x3f of the i/o space is mapped to cpu regs.
+ * As above, we cannot write these from normal store operations.
*/
-void helper_outb(CPUAVRState *env, uint32_t port, uint32_t data)
-{
- data &= 0x000000ff;
- switch (port - 0x38) {
+static uint64_t avr_cpu_reg2_read(void *opaque, hwaddr addr, unsigned size)
+{
+ CPUAVRState *env = opaque;
+
+ switch (addr) {
case REG_38_RAMPD:
- if (avr_feature(env, AVR_FEATURE_RAMPD)) {
- env->rampD = (data & 0xff) << 16;
- }
- break;
+ return 0xff & (env->rampD >> 16);
case REG_38_RAMPX:
- if (avr_feature(env, AVR_FEATURE_RAMPX)) {
- env->rampX = (data & 0xff) << 16;
- }
- break;
+ return 0xff & (env->rampX >> 16);
case REG_38_RAMPY:
- if (avr_feature(env, AVR_FEATURE_RAMPY)) {
- env->rampY = (data & 0xff) << 16;
- }
- break;
+ return 0xff & (env->rampY >> 16);
case REG_38_RAMPZ:
- if (avr_feature(env, AVR_FEATURE_RAMPZ)) {
- env->rampZ = (data & 0xff) << 16;
- }
- break;
+ return 0xff & (env->rampZ >> 16);
case REG_38_EIDN:
- env->eind = (data & 0xff) << 16;
- break;
+ return 0xff & (env->eind >> 16);
case REG_38_SPL:
- env->sp = (env->sp & 0xff00) | (data);
- break;
+ return env->sp & 0x00ff;
case REG_38_SPH:
- if (avr_feature(env, AVR_FEATURE_2_BYTE_SP)) {
- env->sp = (env->sp & 0x00ff) | (data << 8);
- }
- break;
+ return 0xff & (env->sp >> 8);
case REG_38_SREG:
- cpu_set_sreg(env, data);
- break;
- default:
- /* not a special register, pass to normal memory access */
- address_space_stb(&address_space_memory, OFFSET_IO_REGISTERS + port,
- data, MEMTXATTRS_UNSPECIFIED, NULL);
+ return cpu_get_sreg(env);
}
+ g_assert_not_reached();
}
-/*
- * this function implements LD instruction when there is a possibility to read
- * from a CPU register
- */
-target_ulong helper_fullrd(CPUAVRState *env, uint32_t addr)
+static void avr_cpu_trap_write(void *opaque, hwaddr addr,
+ uint64_t data64, unsigned size)
{
- uint8_t data;
+ CPUAVRState *env = opaque;
+ CPUState *cs = env_cpu(env);
- 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 */
- data = address_space_ldub(&address_space_memory, OFFSET_DATA + addr,
- MEMTXATTRS_UNSPECIFIED, NULL);
- }
- return data;
+ env->fullacc = true;
+ cpu_loop_exit_restore(cs, cs->mem_io_pc);
}
+const MemoryRegionOps avr_cpu_reg1 = {
+ .read = avr_cpu_reg1_read,
+ .write = avr_cpu_trap_write,
+ .endianness = DEVICE_NATIVE_ENDIAN,
+ .valid.min_access_size = 1,
+ .valid.max_access_size = 1,
+};
+
+const MemoryRegionOps avr_cpu_reg2 = {
+ .read = avr_cpu_reg2_read,
+ .write = avr_cpu_trap_write,
+ .endianness = DEVICE_NATIVE_ENDIAN,
+ .valid.min_access_size = 1,
+ .valid.max_access_size = 1,
+};
+
/*
* this function implements ST instruction when there is a possibility to
write
* into a CPU register
@@ -339,19 +269,50 @@ void helper_fullwr(CPUAVRState *env, uint32_t data,
uint32_t addr)
{
env->fullacc = false;
- /* Following logic assumes this: */
- assert(OFFSET_IO_REGISTERS == OFFSET_DATA +
- NUMBER_OF_CPU_REGISTERS);
-
- if (addr < NUMBER_OF_CPU_REGISTERS) {
+ switch (addr) {
+ case 0 ... 31:
/* 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 */
+ break;
+
+ case REG_38_RAMPD + 0x38 + NUMBER_OF_CPU_REGISTERS:
+ if (avr_feature(env, AVR_FEATURE_RAMPD)) {
+ env->rampD = data << 16;
+ }
+ break;
+ case REG_38_RAMPX + 0x38 + NUMBER_OF_CPU_REGISTERS:
+ if (avr_feature(env, AVR_FEATURE_RAMPX)) {
+ env->rampX = data << 16;
+ }
+ break;
+ case REG_38_RAMPY + 0x38 + NUMBER_OF_CPU_REGISTERS:
+ if (avr_feature(env, AVR_FEATURE_RAMPY)) {
+ env->rampY = data << 16;
+ }
+ break;
+ case REG_38_RAMPZ + 0x38 + NUMBER_OF_CPU_REGISTERS:
+ if (avr_feature(env, AVR_FEATURE_RAMPZ)) {
+ env->rampZ = data << 16;
+ }
+ break;
+ case REG_38_EIDN + 0x38 + NUMBER_OF_CPU_REGISTERS:
+ env->eind = data << 16;
+ break;
+ case REG_38_SPL + 0x38 + NUMBER_OF_CPU_REGISTERS:
+ env->sp = (env->sp & 0xff00) | data;
+ break;
+ case REG_38_SPH + 0x38 + NUMBER_OF_CPU_REGISTERS:
+ if (avr_feature(env, AVR_FEATURE_2_BYTE_SP)) {
+ env->sp = (env->sp & 0x00ff) | (data << 8);
+ }
+ break;
+ case REG_38_SREG + 0x38 + NUMBER_OF_CPU_REGISTERS:
+ cpu_set_sreg(env, data);
+ break;
+
+ default:
address_space_stb(&address_space_memory, OFFSET_DATA + addr, data,
MEMTXATTRS_UNSPECIFIED, NULL);
+ break;
}
}
diff --git a/target/avr/translate.c b/target/avr/translate.c
index e7f8ced9b3..0490936cd5 100644
--- a/target/avr/translate.c
+++ b/target/avr/translate.c
@@ -194,6 +194,9 @@ static bool avr_have_feature(DisasContext *ctx, int feature)
static bool decode_insn(DisasContext *ctx, uint16_t insn);
#include "decode-insn.c.inc"
+static void gen_inb(DisasContext *ctx, TCGv data, int port);
+static void gen_outb(DisasContext *ctx, TCGv data, int port);
+
/*
* Arithmetic Instructions
*/
@@ -1293,9 +1296,8 @@ static bool trans_SBRS(DisasContext *ctx, arg_SBRS *a)
static bool trans_SBIC(DisasContext *ctx, arg_SBIC *a)
{
TCGv data = tcg_temp_new_i32();
- TCGv port = tcg_constant_i32(a->reg);
- gen_helper_inb(data, tcg_env, port);
+ gen_inb(ctx, data, a->reg);
tcg_gen_andi_tl(data, data, 1 << a->bit);
ctx->skip_cond = TCG_COND_EQ;
ctx->skip_var0 = data;
@@ -1311,9 +1313,8 @@ static bool trans_SBIC(DisasContext *ctx, arg_SBIC *a)
static bool trans_SBIS(DisasContext *ctx, arg_SBIS *a)
{
TCGv data = tcg_temp_new_i32();
- TCGv port = tcg_constant_i32(a->reg);
- gen_helper_inb(data, tcg_env, port);
+ gen_inb(ctx, data, a->reg);
tcg_gen_andi_tl(data, data, 1 << a->bit);
ctx->skip_cond = TCG_COND_NE;
ctx->skip_var0 = data;
@@ -1502,11 +1503,18 @@ static void gen_data_store(DisasContext *ctx, TCGv
data, TCGv addr)
static void gen_data_load(DisasContext *ctx, TCGv data, TCGv addr)
{
- if (ctx->base.tb->flags & TB_FLAGS_FULL_ACCESS) {
- gen_helper_fullrd(data, tcg_env, addr);
- } else {
- tcg_gen_qemu_ld_tl(data, addr, MMU_DATA_IDX, MO_UB);
- }
+ tcg_gen_qemu_ld_tl(data, addr, MMU_DATA_IDX, MO_UB);
+}
+
+static void gen_inb(DisasContext *ctx, TCGv data, int port)
+{
+ gen_data_load(ctx, data, tcg_constant_i32(port + NUMBER_OF_CPU_REGISTERS));
+}
+
+static void gen_outb(DisasContext *ctx, TCGv data, int port)
+{
+ gen_helper_fullwr(tcg_env, data,
+ tcg_constant_i32(port + NUMBER_OF_CPU_REGISTERS));
}
/*
@@ -2126,9 +2134,8 @@ static bool trans_SPMX(DisasContext *ctx, arg_SPMX *a)
static bool trans_IN(DisasContext *ctx, arg_IN *a)
{
TCGv Rd = cpu_r[a->rd];
- TCGv port = tcg_constant_i32(a->imm);
- gen_helper_inb(Rd, tcg_env, port);
+ gen_inb(ctx, Rd, a->imm);
return true;
}
@@ -2139,9 +2146,8 @@ static bool trans_IN(DisasContext *ctx, arg_IN *a)
static bool trans_OUT(DisasContext *ctx, arg_OUT *a)
{
TCGv Rd = cpu_r[a->rd];
- TCGv port = tcg_constant_i32(a->imm);
- gen_helper_outb(tcg_env, port, Rd);
+ gen_outb(ctx, Rd, a->imm);
return true;
}
@@ -2407,11 +2413,10 @@ static bool trans_SWAP(DisasContext *ctx, arg_SWAP *a)
static bool trans_SBI(DisasContext *ctx, arg_SBI *a)
{
TCGv data = tcg_temp_new_i32();
- TCGv port = tcg_constant_i32(a->reg);
- gen_helper_inb(data, tcg_env, port);
+ gen_inb(ctx, data, a->reg);
tcg_gen_ori_tl(data, data, 1 << a->bit);
- gen_helper_outb(tcg_env, port, data);
+ gen_outb(ctx, data, a->reg);
return true;
}
@@ -2422,11 +2427,10 @@ static bool trans_SBI(DisasContext *ctx, arg_SBI *a)
static bool trans_CBI(DisasContext *ctx, arg_CBI *a)
{
TCGv data = tcg_temp_new_i32();
- TCGv port = tcg_constant_i32(a->reg);
- gen_helper_inb(data, tcg_env, port);
+ gen_inb(ctx, data, a->reg);
tcg_gen_andi_tl(data, data, ~(1 << a->bit));
- gen_helper_outb(tcg_env, port, data);
+ gen_outb(ctx, data, a->reg);
return true;
}
--
2.43.0
