#include <algorithm>
#include <cassert>
+#include <cinttypes>
#include <cstdio>
#include <vector>
#include "sim.h"
#include "gdbserver.h"
#include "mmu.h"
-
-#define C_EBREAK 0x9002
-#define EBREAK 0x00100073
+#include "encoding.h"
//////////////////////////////////////// Utility Functions
# define D(x)
#endif // DEBUG
-const int debug_gdbserver = 0;
-
void die(const char* msg)
{
fprintf(stderr, "gdbserver code died: %s\n", msg);
REG_FPR0 = 33,
REG_FPR31 = 64,
REG_CSR0 = 65,
+ REG_MSTATUS = CSR_MSTATUS + REG_CSR0,
REG_CSR4095 = 4160,
- REG_END = 4161
+ REG_PRIV = 4161
};
//////////////////////////////////////// Functions to generate RISC-V opcodes.
MATCH_FSD;
}
-static uint32_t flw(unsigned int src, unsigned int base, uint16_t offset)
+static uint32_t flw(unsigned int dest, unsigned int base, uint16_t offset)
{
- return (bits(offset, 11, 5) << 25) |
- (bits(src, 4, 0) << 20) |
+ return (bits(offset, 11, 0) << 20) |
(base << 15) |
- (bits(offset, 4, 0) << 7) |
+ (bits(dest, 4, 0) << 7) |
MATCH_FLW;
}
-static uint32_t fld(unsigned int src, unsigned int base, uint16_t offset)
+static uint32_t fld(unsigned int dest, unsigned int base, uint16_t offset)
{
- return (bits(offset, 11, 5) << 25) |
- (bits(src, 4, 0) << 20) |
+ return (bits(offset, 11, 0) << 20) |
(base << 15) |
- (bits(offset, 4, 0) << 7) |
+ (bits(dest, 4, 0) << 7) |
MATCH_FLD;
}
count -= copy;
if (count > 0) {
assert(count < contiguous_empty_size());
- memcpy(contiguous_empty(), src, count * sizeof(T));
+ memcpy(contiguous_empty(), src+copy, count * sizeof(T));
data_added(count);
}
}
bool perform_step(unsigned int step) {
switch (state) {
+ gs.tselect_valid = false;
case ST_ENTER:
if (gs.xlen == 0) {
gs.dr_write32(0, xori(S1, ZERO, -1));
case ST_MSTATUS:
gs.mstatus = gs.dr_read(SLOT_DATA0);
+ gs.mstatus_dirty = false;
gs.dr_write32(0, csrr(S0, CSR_DCSR));
gs.dr_write32(1, sw(S0, 0, (uint16_t) DEBUG_RAM_START + 16));
gs.dr_write_jump(2);
break;
}
}
+
return true;
default:
operation_t(gdbserver), single_step(single_step) {};
bool perform_step(unsigned int step) {
+ D(fprintf(stderr, "continue step %d\n", step));
switch (step) {
case 0:
gs.dr_write_load(0, S0, SLOT_DATA0);
switch (step) {
case 0:
if (reg >= REG_XPR0 && reg <= REG_XPR31) {
- die("handle_register_read");
- // send(p->state.XPR[reg - REG_XPR0]);
+ unsigned int i = 0;
+ if (reg == S0) {
+ gs.dr_write32(i++, csrr(S0, CSR_DSCRATCH));
+ }
+ if (gs.xlen == 32) {
+ gs.dr_write32(i++, sw(reg - REG_XPR0, 0, (uint16_t) DEBUG_RAM_START + 16));
+ } else {
+ gs.dr_write32(i++, sd(reg - REG_XPR0, 0, (uint16_t) DEBUG_RAM_START + 16));
+ }
+ gs.dr_write_jump(i);
} else if (reg == REG_PC) {
gs.start_packet();
if (gs.xlen == 32) {
gs.end_packet();
return true;
} else if (reg >= REG_FPR0 && reg <= REG_FPR31) {
- // send(p->state.FPR[reg - REG_FPR0]);
+ gs.dr_write_load(0, S0, SLOT_DATA1);
+ gs.dr_write(SLOT_DATA1, set_field(gs.mstatus, MSTATUS_FS, 1));
+ gs.dr_write32(1, csrw(S0, CSR_MSTATUS));
+ gs.mstatus_dirty = true;
+ if (gs.xlen == 32) {
+ gs.dr_write32(2, fsw(reg - REG_FPR0, 0, (uint16_t) DEBUG_RAM_START + 16));
+ } else {
+ gs.dr_write32(2, fsd(reg - REG_FPR0, 0, (uint16_t) DEBUG_RAM_START + 16));
+ }
+ gs.dr_write_jump(3);
+ } else if (reg == REG_MSTATUS) {
+ gs.start_packet();
if (gs.xlen == 32) {
- gs.dr_write32(0, fsw(reg - REG_FPR0, 0, (uint16_t) DEBUG_RAM_START + 16));
+ gs.send((uint32_t) gs.mstatus);
} else {
- gs.dr_write32(0, fsd(reg - REG_FPR0, 0, (uint16_t) DEBUG_RAM_START + 16));
+ gs.send(gs.mstatus);
}
- gs.dr_write_jump(1);
+ gs.end_packet();
+ return true;
} else if (reg >= REG_CSR0 && reg <= REG_CSR4095) {
gs.dr_write32(0, csrr(S0, reg - REG_CSR0));
gs.dr_write_store(1, S0, SLOT_DATA0);
// If we hit an exception reading the CSR, we'll end up returning ~0 as
// the register's value, which is what we want. (Right?)
gs.dr_write(SLOT_DATA0, ~(uint64_t) 0);
+ } else if (reg == REG_PRIV) {
+ gs.start_packet();
+ gs.send((uint8_t) get_field(gs.dcsr, DCSR_PRV));
+ gs.end_packet();
+ return true;
} else {
gs.send_packet("E02");
return true;
return false;
case 1:
- gs.start_packet();
- if (gs.xlen == 32) {
- gs.send(gs.dr_read32(4));
- } else {
- gs.send(gs.dr_read(SLOT_DATA0));
+ {
+ unsigned result = gs.dr_read32(DEBUG_RAM_SIZE / 4 - 1);
+ if (result) {
+ gs.send_packet("E03");
+ return true;
+ }
+ gs.start_packet();
+ if (gs.xlen == 32) {
+ gs.send(gs.dr_read32(4));
+ } else {
+ gs.send(gs.dr_read(SLOT_DATA0));
+ }
+ gs.end_packet();
+ return true;
}
- gs.end_packet();
- return true;
}
return false;
}
bool perform_step(unsigned int step)
{
- gs.dr_write_load(0, S0, SLOT_DATA0);
- gs.dr_write(SLOT_DATA0, value);
- if (reg == S0) {
- gs.dr_write32(1, csrw(S0, CSR_DSCRATCH));
- gs.dr_write_jump(2);
- } else if (reg == S1) {
- gs.dr_write_store(1, S0, SLOT_DATA_LAST);
- gs.dr_write_jump(2);
- } else if (reg >= REG_XPR0 && reg <= REG_XPR31) {
- gs.dr_write32(1, addi(reg, S0, 0));
- gs.dr_write_jump(2);
- } else if (reg == REG_PC) {
- gs.dpc = value;
- return true;
- } else if (reg >= REG_FPR0 && reg <= REG_FPR31) {
- if (gs.xlen == 32) {
- gs.dr_write32(0, flw(reg - REG_FPR0, 0, (uint16_t) DEBUG_RAM_START + 16));
- } else {
- gs.dr_write32(0, fld(reg - REG_FPR0, 0, (uint16_t) DEBUG_RAM_START + 16));
- }
- gs.dr_write_jump(1);
- } else if (reg >= REG_CSR0 && reg <= REG_CSR4095) {
- gs.dr_write32(1, csrw(S0, reg - REG_CSR0));
- gs.dr_write_jump(2);
- if (reg == REG_CSR0 + CSR_SPTBR) {
- gs.sptbr = value;
- gs.sptbr_valid = true;
- }
- } else {
- gs.send_packet("E02");
- return true;
+ switch (step) {
+ case 0:
+ gs.dr_write_load(0, S0, SLOT_DATA0);
+ gs.dr_write(SLOT_DATA0, value);
+ if (reg == S0) {
+ gs.dr_write32(1, csrw(S0, CSR_DSCRATCH));
+ gs.dr_write_jump(2);
+ } else if (reg == S1) {
+ gs.dr_write_store(1, S0, SLOT_DATA_LAST);
+ gs.dr_write_jump(2);
+ } else if (reg >= REG_XPR0 && reg <= REG_XPR31) {
+ gs.dr_write32(1, addi(reg, S0, 0));
+ gs.dr_write_jump(2);
+ } else if (reg == REG_PC) {
+ gs.dpc = value;
+ return true;
+ } else if (reg >= REG_FPR0 && reg <= REG_FPR31) {
+ gs.dr_write_load(0, S0, SLOT_DATA1);
+ gs.dr_write(SLOT_DATA1, set_field(gs.mstatus, MSTATUS_FS, 1));
+ gs.dr_write32(1, csrw(S0, CSR_MSTATUS));
+ gs.mstatus_dirty = true;
+ if (gs.xlen == 32) {
+ gs.dr_write32(2, flw(reg - REG_FPR0, 0, (uint16_t) DEBUG_RAM_START + 16));
+ } else {
+ gs.dr_write32(2, fld(reg - REG_FPR0, 0, (uint16_t) DEBUG_RAM_START + 16));
+ }
+ gs.dr_write_jump(3);
+ } else if (reg == REG_MSTATUS) {
+ gs.mstatus = value;
+ gs.mstatus_dirty = true;
+ return true;
+ } else if (reg >= REG_CSR0 && reg <= REG_CSR4095) {
+ gs.dr_write32(1, csrw(S0, reg - REG_CSR0));
+ gs.dr_write_jump(2);
+ if (reg == REG_CSR0 + CSR_SPTBR) {
+ gs.sptbr = value;
+ gs.sptbr_valid = true;
+ }
+ } else if (reg == REG_PRIV) {
+ gs.dcsr = set_field(gs.dcsr, DCSR_PRV, value);
+ return true;
+ } else {
+ gs.send_packet("E02");
+ return true;
+ }
+ gs.set_interrupt(0);
+ return false;
+
+ case 1:
+ {
+ unsigned result = gs.dr_read32(DEBUG_RAM_SIZE / 4 - 1);
+ if (result) {
+ gs.send_packet("E03");
+ return true;
+ }
+ gs.send_packet("OK");
+ return true;
+ }
}
- gs.set_interrupt(0);
- gs.send_packet("OK");
- return true;
+
+ assert(0);
}
private:
// If data is NULL, send the result straight to gdb.
memory_read_op_t(gdbserver_t& gdbserver, reg_t vaddr, unsigned int length,
unsigned char *data=NULL) :
- operation_t(gdbserver), vaddr(vaddr), length(length), data(data) {};
+ operation_t(gdbserver), vaddr(vaddr), length(length), data(data), index(0)
+ {
+ buf = new uint8_t[length];
+ };
+
+ ~memory_read_op_t()
+ {
+ delete[] buf;
+ }
bool perform_step(unsigned int step)
{
gs.dr_write(SLOT_DATA0, paddr);
gs.set_interrupt(0);
- if (!data) {
- gs.start_packet();
- }
return false;
}
- char buffer[3];
+ if (gs.dr_read32(DEBUG_RAM_SIZE / 4 - 1)) {
+ // Note that OpenOCD doesn't report this error to gdb by default. They
+ // think it can mess up stack tracing. So far I haven't seen any
+ // problems.
+ gs.send_packet("E99");
+ return true;
+ }
+
reg_t value = gs.dr_read(SLOT_DATA1);
for (unsigned int i = 0; i < access_size; i++) {
if (data) {
*(data++) = value & 0xff;
D(fprintf(stderr, "%02x", (unsigned int) (value & 0xff)));
} else {
- sprintf(buffer, "%02x", (unsigned int) (value & 0xff));
- gs.send(buffer);
+ buf[index++] = value & 0xff;
}
value >>= 8;
}
- if (data && debug_gdbserver) {
+ if (data) {
D(fprintf(stderr, "\n"));
}
length -= access_size;
if (length == 0) {
if (!data) {
+ gs.start_packet();
+ char buffer[3];
+ for (unsigned int i = 0; i < index; i++) {
+ sprintf(buffer, "%02x", (unsigned int) buf[i]);
+ gs.send(buffer);
+ }
gs.end_packet();
}
return true;
unsigned char* data;
reg_t paddr;
unsigned int access_size;
+ unsigned int index;
+ uint8_t *buf;
};
class memory_write_op_t : public operation_t
if (step == 0) {
access_size = gs.find_access_size(paddr, length);
- D(fprintf(stderr, "write to 0x%lx -> 0x%lx (access=%d): ", vaddr, paddr,
- access_size));
+ D(fprintf(stderr, "write to 0x%" PRIx64 " -> 0x%" PRIx64 " (access=%d): ",
+ vaddr, paddr, access_size));
for (unsigned int i = 0; i < length; i++) {
D(fprintf(stderr, "%02x", data[i]));
}
(data[6] << 16) | (data[7] << 24));
break;
default:
- fprintf(stderr, "gdbserver error: write %d bytes to 0x%lx -> 0x%lx; "
- "access_size=%d\n", length, vaddr, paddr, access_size);
+ fprintf(stderr, "gdbserver error: write %d bytes to 0x%016" PRIx64
+ " -> 0x%016" PRIx64 "; access_size=%d\n",
+ length, vaddr, paddr, access_size);
gs.send_packet("E12");
return true;
}
}
if (gs.dr_read32(DEBUG_RAM_SIZE / 4 - 1)) {
- fprintf(stderr, "Exception happened while writing to 0x%lx -> 0x%lx\n",
- vaddr, paddr);
+ gs.send_packet("E98");
+ return true;
}
offset += access_size;
bool perform_step(unsigned int step)
{
- unsigned int vm = gs.virtual_memory();
-
- if (step == 0) {
- switch (vm) {
- case VM_MBARE:
- // Nothing to be done.
- return true;
-
- case VM_SV32:
- levels = 2;
- ptidxbits = 10;
- ptesize = 4;
- break;
- case VM_SV39:
- levels = 3;
- ptidxbits = 9;
- ptesize = 8;
- break;
- case VM_SV48:
- levels = 4;
- ptidxbits = 9;
- ptesize = 8;
- break;
-
- default:
- {
- char buf[100];
- sprintf(buf, "VM mode %d is not supported by gdbserver.cc.", vm);
- die(buf);
- return true; // die doesn't return, but gcc doesn't know that.
- }
- }
- }
-
// Perform any reads from the just-completed action.
switch (state) {
case STATE_START:
break;
case STATE_READ_SPTBR:
- gs.sptbr = ((uint64_t) gs.dr_read32(5) << 32) | gs.dr_read32(4);
+ gs.sptbr = gs.dr_read(SLOT_DATA0);
gs.sptbr_valid = true;
+ vm = decode_vm_info(gs.xlen, gs.privilege_mode(), gs.sptbr);
+ if (vm.levels == 0)
+ return true;
break;
case STATE_READ_PTE:
- gs.pte_cache[pte_addr] = ((uint64_t) gs.dr_read32(5) << 32) |
- gs.dr_read32(4);
- D(fprintf(stderr, "pte_cache[0x%lx] = 0x%lx\n", pte_addr, gs.pte_cache[pte_addr]));
+ if (vm.ptesize == 4) {
+ gs.pte_cache[pte_addr] = gs.dr_read32(4);
+ } else {
+ gs.pte_cache[pte_addr] = ((uint64_t) gs.dr_read32(5) << 32) |
+ gs.dr_read32(4);
+ }
+ D(fprintf(stderr, "pte_cache[0x%" PRIx64 "] = 0x%" PRIx64 "\n", pte_addr,
+ gs.pte_cache[pte_addr]));
break;
}
if (!gs.sptbr_valid) {
state = STATE_READ_SPTBR;
gs.dr_write32(0, csrr(S0, CSR_SPTBR));
- gs.dr_write32(1, sd(S0, 0, (uint16_t) DEBUG_RAM_START + 16));
- gs.dr_write32(2, jal(0, (uint32_t) (DEBUG_ROM_RESUME - (DEBUG_RAM_START + 4*2))));
+ gs.dr_write_store(1, S0, SLOT_DATA0);
+ gs.dr_write_jump(2);
gs.set_interrupt(0);
return false;
}
- reg_t base = gs.sptbr << PGSHIFT;
- int ptshift = (levels - 1) * ptidxbits;
- for (unsigned int i = 0; i < levels; i++, ptshift -= ptidxbits) {
- reg_t idx = (vaddr >> (PGSHIFT + ptshift)) & ((1 << ptidxbits) - 1);
+ reg_t base = vm.ptbase;
+ for (int i = vm.levels - 1; i >= 0; i--) {
+ int ptshift = i * vm.idxbits;
+ reg_t idx = (vaddr >> (PGSHIFT + ptshift)) & ((1 << vm.idxbits) - 1);
- pte_addr = base + idx * ptesize;
+ pte_addr = base + idx * vm.ptesize;
auto it = gs.pte_cache.find(pte_addr);
if (it == gs.pte_cache.end()) {
state = STATE_READ_PTE;
- if (ptesize == 4) {
+ if (vm.ptesize == 4) {
gs.dr_write32(0, lw(S0, 0, (uint16_t) DEBUG_RAM_START + 16));
gs.dr_write32(1, lw(S1, S0, 0));
gs.dr_write32(2, sw(S1, 0, (uint16_t) DEBUG_RAM_START + 16));
gs.dr_write32(1, ld(S1, S0, 0));
gs.dr_write32(2, sd(S1, 0, (uint16_t) DEBUG_RAM_START + 16));
}
- gs.dr_write32(3, jal(0, (uint32_t) (DEBUG_ROM_RESUME - (DEBUG_RAM_START + 4*3))));
+ gs.dr_write_jump(3);
gs.dr_write32(4, pte_addr);
gs.dr_write32(5, pte_addr >> 32);
gs.set_interrupt(0);
}
}
fprintf(stderr,
- "ERROR: gdbserver couldn't find appropriate PTEs to translate 0x%lx\n",
+ "ERROR: gdbserver couldn't find appropriate PTEs to translate 0x%016" PRIx64 "\n",
vaddr);
return true;
}
} state;
reg_t vaddr;
size_t length;
- unsigned int levels;
- unsigned int ptidxbits;
- unsigned int ptesize;
+ vm_info vm;
reg_t pte_addr;
};
+class hardware_breakpoint_insert_op_t : public operation_t
+{
+ public:
+ hardware_breakpoint_insert_op_t(gdbserver_t& gdbserver,
+ hardware_breakpoint_t bp) :
+ operation_t(gdbserver), state(STATE_START), bp(bp) {};
+
+ void write_new_index_program()
+ {
+ gs.dr_write_load(0, S0, SLOT_DATA1);
+ gs.dr_write32(1, csrw(S0, CSR_TSELECT));
+ gs.dr_write32(2, csrr(S0, CSR_TSELECT));
+ gs.dr_write_store(3, S0, SLOT_DATA1);
+ gs.dr_write_jump(4);
+ gs.dr_write(SLOT_DATA1, bp.index);
+ }
+
+ bool perform_step(unsigned int step)
+ {
+ switch (state) {
+ case STATE_START:
+ bp.index = 0;
+ write_new_index_program();
+ state = STATE_CHECK_INDEX;
+ break;
+
+ case STATE_CHECK_INDEX:
+ if (gs.dr_read(SLOT_DATA1) != bp.index) {
+ // We've exhausted breakpoints without finding an appropriate one.
+ gs.send_packet("E58");
+ return true;
+ }
+
+ gs.dr_write32(0, csrr(S0, CSR_TDATA1));
+ gs.dr_write_store(1, S0, SLOT_DATA0);
+ gs.dr_write_jump(2);
+ state = STATE_CHECK_MCONTROL;
+ break;
+
+ case STATE_CHECK_MCONTROL:
+ {
+ reg_t mcontrol = gs.dr_read(SLOT_DATA0);
+ unsigned int type = mcontrol >> (gs.xlen - 4);
+ if (type == 0) {
+ // We've exhausted breakpoints without finding an appropriate one.
+ gs.send_packet("E58");
+ return true;
+ }
+
+ if (type == 2 &&
+ !get_field(mcontrol, MCONTROL_EXECUTE) &&
+ !get_field(mcontrol, MCONTROL_LOAD) &&
+ !get_field(mcontrol, MCONTROL_STORE)) {
+ // Found an unused trigger.
+ gs.dr_write_load(0, S0, SLOT_DATA1);
+ gs.dr_write32(1, csrw(S0, CSR_TDATA1));
+ gs.dr_write_jump(2);
+ mcontrol = set_field(0, MCONTROL_ACTION, MCONTROL_ACTION_DEBUG_MODE);
+ mcontrol = set_field(mcontrol, MCONTROL_DMODE(gs.xlen), 1);
+ mcontrol = set_field(mcontrol, MCONTROL_MATCH, MCONTROL_MATCH_EQUAL);
+ mcontrol = set_field(mcontrol, MCONTROL_M, 1);
+ mcontrol = set_field(mcontrol, MCONTROL_H, 1);
+ mcontrol = set_field(mcontrol, MCONTROL_S, 1);
+ mcontrol = set_field(mcontrol, MCONTROL_U, 1);
+ mcontrol = set_field(mcontrol, MCONTROL_EXECUTE, bp.execute);
+ mcontrol = set_field(mcontrol, MCONTROL_LOAD, bp.load);
+ mcontrol = set_field(mcontrol, MCONTROL_STORE, bp.store);
+ // For store triggers it's nicer to fire just before the
+ // instruction than just after. However, gdb doesn't clear the
+ // breakpoints and step before resuming from a store trigger.
+ // That means that without extra code, you'll keep hitting the
+ // same watchpoint over and over again. That's not useful at all.
+ // Instead of fixing this the right way, just set timing=1 for
+ // those triggers.
+ if (bp.load || bp.store)
+ mcontrol = set_field(mcontrol, MCONTROL_TIMING, 1);
+
+ gs.dr_write(SLOT_DATA1, mcontrol);
+ state = STATE_WRITE_ADDRESS;
+ } else {
+ bp.index++;
+ write_new_index_program();
+ state = STATE_CHECK_INDEX;
+ }
+ }
+ break;
+
+ case STATE_WRITE_ADDRESS:
+ {
+ gs.dr_write_load(0, S0, SLOT_DATA1);
+ gs.dr_write32(1, csrw(S0, CSR_TDATA2));
+ gs.dr_write_jump(2);
+ gs.dr_write(SLOT_DATA1, bp.vaddr);
+ gs.set_interrupt(0);
+ gs.send_packet("OK");
+
+ gs.hardware_breakpoints.insert(bp);
+
+ return true;
+ }
+ }
+
+ gs.set_interrupt(0);
+ return false;
+ }
+
+ private:
+ enum {
+ STATE_START,
+ STATE_CHECK_INDEX,
+ STATE_CHECK_MCONTROL,
+ STATE_WRITE_ADDRESS
+ } state;
+ hardware_breakpoint_t bp;
+};
+
+class maybe_save_tselect_op_t : public operation_t
+{
+ public:
+ maybe_save_tselect_op_t(gdbserver_t& gdbserver) : operation_t(gdbserver) {};
+ bool perform_step(unsigned int step) {
+ if (gs.tselect_valid)
+ return true;
+
+ switch (step) {
+ case 0:
+ gs.dr_write32(0, csrr(S0, CSR_TDATA1));
+ gs.dr_write_store(1, S0, SLOT_DATA0);
+ gs.dr_write_jump(2);
+ gs.set_interrupt(0);
+ return false;
+ case 1:
+ gs.tselect = gs.dr_read(SLOT_DATA0);
+ gs.tselect_valid = true;
+ break;
+ }
+ return true;
+ }
+};
+
+class maybe_restore_tselect_op_t : public operation_t
+{
+ public:
+ maybe_restore_tselect_op_t(gdbserver_t& gdbserver) : operation_t(gdbserver) {};
+ bool perform_step(unsigned int step) {
+ if (gs.tselect_valid) {
+ gs.dr_write_load(0, S0, SLOT_DATA1);
+ gs.dr_write32(1, csrw(S0, CSR_TSELECT));
+ gs.dr_write_jump(2);
+ gs.dr_write(SLOT_DATA1, gs.tselect);
+ }
+ return true;
+ }
+};
+
+class maybe_restore_mstatus_op_t : public operation_t
+{
+ public:
+ maybe_restore_mstatus_op_t(gdbserver_t& gdbserver) : operation_t(gdbserver) {};
+ bool perform_step(unsigned int step) {
+ if (gs.mstatus_dirty) {
+ gs.dr_write_load(0, S0, SLOT_DATA1);
+ gs.dr_write32(1, csrw(S0, CSR_MSTATUS));
+ gs.dr_write_jump(2);
+ gs.dr_write(SLOT_DATA1, gs.mstatus);
+ }
+ return true;
+ }
+};
+
+class hardware_breakpoint_remove_op_t : public operation_t
+{
+ public:
+ hardware_breakpoint_remove_op_t(gdbserver_t& gdbserver,
+ hardware_breakpoint_t bp) :
+ operation_t(gdbserver), bp(bp) {};
+
+ bool perform_step(unsigned int step) {
+ gs.dr_write32(0, addi(S0, ZERO, bp.index));
+ gs.dr_write32(1, csrw(S0, CSR_TSELECT));
+ gs.dr_write32(2, csrw(ZERO, CSR_TDATA1));
+ gs.dr_write_jump(3);
+ gs.set_interrupt(0);
+ return true;
+ }
+
+ private:
+ hardware_breakpoint_t bp;
+};
+
////////////////////////////// gdbserver itself
gdbserver_t::gdbserver_t(uint16_t port, sim_t *sim) :
xlen(0),
sim(sim),
client_fd(0),
- recv_buf(64 * 1024), send_buf(64 * 1024)
+ // gdb likes to send 0x100000 bytes at once when downloading.
+ recv_buf(0x180000), send_buf(64 * 1024)
{
socket_fd = socket(AF_INET, SOCK_STREAM, 0);
if (socket_fd == -1) {
reg_t gdbserver_t::translate(reg_t vaddr)
{
- unsigned int vm = virtual_memory();
- unsigned int levels, ptidxbits, ptesize;
-
- switch (vm) {
- case VM_MBARE:
- return vaddr;
-
- case VM_SV32:
- levels = 2;
- ptidxbits = 10;
- ptesize = 4;
- break;
- case VM_SV39:
- levels = 3;
- ptidxbits = 9;
- ptesize = 8;
- break;
- case VM_SV48:
- levels = 4;
- ptidxbits = 9;
- ptesize = 8;
- break;
-
- default:
- {
- char buf[100];
- sprintf(buf, "VM mode %d is not supported by gdbserver.cc.", vm);
- die(buf);
- return true; // die doesn't return, but gcc doesn't know that.
- }
- }
+ vm_info vm = decode_vm_info(xlen, privilege_mode(), sptbr);
+ if (vm.levels == 0)
+ return vaddr;
// Handle page tables here. There's a bunch of duplicated code with
// collect_translation_info_op_t. :-(
- reg_t base = sptbr << PGSHIFT;
- int ptshift = (levels - 1) * ptidxbits;
- for (unsigned int i = 0; i < levels; i++, ptshift -= ptidxbits) {
- reg_t idx = (vaddr >> (PGSHIFT + ptshift)) & ((1 << ptidxbits) - 1);
+ reg_t base = vm.ptbase;
+ for (int i = vm.levels - 1; i >= 0; i--) {
+ int ptshift = i * vm.idxbits;
+ reg_t idx = (vaddr >> (PGSHIFT + ptshift)) & ((1 << vm.idxbits) - 1);
- reg_t pte_addr = base + idx * ptesize;
+ reg_t pte_addr = base + idx * vm.ptesize;
auto it = pte_cache.find(pte_addr);
if (it == pte_cache.end()) {
- fprintf(stderr, "ERROR: gdbserver tried to translate 0x%lx without first "
- "collecting the relevant PTEs.\n", vaddr);
+ fprintf(stderr, "ERROR: gdbserver tried to translate 0x%016" PRIx64
+ " without first collecting the relevant PTEs.\n", vaddr);
die("gdbserver_t::translate()");
}
reg_t vpn = vaddr >> PGSHIFT;
reg_t paddr = (ppn | (vpn & ((reg_t(1) << ptshift) - 1))) << PGSHIFT;
paddr += vaddr & (PGSIZE-1);
- D(fprintf(stderr, "gdbserver translate 0x%lx -> 0x%lx\n", vaddr, paddr));
+ D(fprintf(stderr, "gdbserver translate 0x%" PRIx64 " -> 0x%" PRIx64 "\n", vaddr, paddr));
return paddr;
}
}
- fprintf(stderr, "ERROR: gdbserver tried to translate 0x%lx but the relevant "
- "PTEs are invalid.\n", vaddr);
+ fprintf(stderr, "ERROR: gdbserver tried to translate 0x%016" PRIx64
+ " but the relevant PTEs are invalid.\n", vaddr);
// TODO: Is it better to throw an exception here?
return -1;
}
return mode;
}
-unsigned int gdbserver_t::virtual_memory()
-{
- unsigned int mode = privilege_mode();
- if (mode == PRV_M)
- return VM_MBARE;
- return get_field(mstatus, MSTATUS_VM);
-}
-
void gdbserver_t::dr_write32(unsigned int index, uint32_t value)
{
sim->debug_module.ram_write32(index, value);
// available.
size_t count = recv_buf.contiguous_empty_size();
- assert(count > 0);
ssize_t bytes = ::read(client_fd, recv_buf.contiguous_empty(), count);
if (bytes == -1) {
if (errno == EAGAIN) {
// Client can't take any more data right now.
break;
} else {
- D(fprintf(stderr, "wrote %ld bytes: ", bytes));
- for (unsigned int i = 0; i < bytes; i++) {
+ D(fprintf(stderr, "wrote %zd bytes: ", bytes));
+ for (int i = 0; i < bytes; i++) {
D(fprintf(stderr, "%c", send_buf[i]));
}
D(fprintf(stderr, "\n"));
if (b == '$') {
// Start of new packet.
if (!packet.empty()) {
- fprintf(stderr, "Received malformed %ld-byte packet from debug client: ",
+ fprintf(stderr, "Received malformed %zd-byte packet from debug client: ",
packet.size());
print_packet(packet);
recv_buf.consume(i);
break;
}
}
+
+ if (recv_buf.full()) {
+ fprintf(stderr,
+ "Receive buffer is full, but no complete packet was found!\n");
+ for (unsigned line = 0; line < 8; line++) {
+ for (unsigned i = 0; i < 16; i++) {
+ fprintf(stderr, "%02x ", recv_buf.entry(line * 16 + i));
+ }
+ for (unsigned i = 0; i < 16; i++) {
+ uint8_t e = recv_buf.entry(line * 16 + i);
+ if (e >= ' ' && e <= '~')
+ fprintf(stderr, "%c", e);
+ else
+ fprintf(stderr, ".");
+ }
+ fprintf(stderr, "\n");
+ }
+ assert(!recv_buf.full());
+ }
}
void gdbserver_t::handle_halt_reason(const std::vector<uint8_t> &packet)
// First byte is the least-significant one.
// Eg. "08675309" becomes 0x09536708
-uint64_t consume_hex_number_le(std::vector<uint8_t>::const_iterator &iter,
+uint64_t gdbserver_t::consume_hex_number_le(
+ std::vector<uint8_t>::const_iterator &iter,
std::vector<uint8_t>::const_iterator end)
{
uint64_t value = 0;
else
shift -= 4;
}
+ if (shift > (xlen+4)) {
+ fprintf(stderr,
+ "gdb sent too many data bytes. That means it thinks XLEN is greater "
+ "than %d.\nTo fix that, tell gdb: set arch riscv:rv%d\n",
+ xlen, xlen);
+ }
return value;
}
processor_t *p = sim->get_core(0);
add_operation(new register_write_op_t(*this, n, value));
-
- return send_packet("OK");
}
void gdbserver_t::handle_memory_read(const std::vector<uint8_t> &packet)
return send_packet("E30");
}
+ add_operation(new maybe_restore_tselect_op_t(*this));
+ add_operation(new maybe_restore_mstatus_op_t(*this));
add_operation(new continue_op_t(*this, false));
}
return send_packet("E40");
}
+ add_operation(new maybe_restore_tselect_op_t(*this));
add_operation(new continue_op_t(*this, true));
}
extended_mode = true;
}
+void gdbserver_t::software_breakpoint_insert(reg_t vaddr, unsigned int size)
+{
+ fence_i_required = true;
+ add_operation(new collect_translation_info_op_t(*this, vaddr, size));
+ unsigned char* inst = new unsigned char[4];
+ if (size == 2) {
+ inst[0] = MATCH_C_EBREAK & 0xff;
+ inst[1] = (MATCH_C_EBREAK >> 8) & 0xff;
+ } else {
+ inst[0] = MATCH_EBREAK & 0xff;
+ inst[1] = (MATCH_EBREAK >> 8) & 0xff;
+ inst[2] = (MATCH_EBREAK >> 16) & 0xff;
+ inst[3] = (MATCH_EBREAK >> 24) & 0xff;
+ }
+
+ software_breakpoint_t bp = {
+ .vaddr = vaddr,
+ .size = size
+ };
+ software_breakpoints[vaddr] = bp;
+ add_operation(new memory_read_op_t(*this, bp.vaddr, bp.size,
+ software_breakpoints[bp.vaddr].instruction));
+ add_operation(new memory_write_op_t(*this, bp.vaddr, bp.size, inst));
+}
+
+void gdbserver_t::software_breakpoint_remove(reg_t vaddr, unsigned int size)
+{
+ fence_i_required = true;
+ add_operation(new collect_translation_info_op_t(*this, vaddr, size));
+
+ software_breakpoint_t found_bp = software_breakpoints[vaddr];
+ unsigned char* instruction = new unsigned char[4];
+ memcpy(instruction, found_bp.instruction, 4);
+ add_operation(new memory_write_op_t(*this, found_bp.vaddr,
+ found_bp.size, instruction));
+ software_breakpoints.erase(vaddr);
+}
+
+void gdbserver_t::hardware_breakpoint_insert(const hardware_breakpoint_t &bp)
+{
+ add_operation(new maybe_save_tselect_op_t(*this));
+ add_operation(new hardware_breakpoint_insert_op_t(*this, bp));
+}
+
+void gdbserver_t::hardware_breakpoint_remove(const hardware_breakpoint_t &bp)
+{
+ add_operation(new maybe_save_tselect_op_t(*this));
+ hardware_breakpoint_t found = *hardware_breakpoints.find(bp);
+ add_operation(new hardware_breakpoint_remove_op_t(*this, found));
+}
+
void gdbserver_t::handle_breakpoint(const std::vector<uint8_t> &packet)
{
- // insert: Z type,addr,kind
- // remove: z type,addr,kind
+ // insert: Z type,addr,length
+ // remove: z type,addr,length
+
+ // type: 0 - software breakpoint, 1 - hardware breakpoint, 2 - write
+ // watchpoint, 3 - read watchpoint, 4 - access watchpoint; addr is address;
+ // length is in bytes. For a software breakpoint, length specifies the size
+ // of the instruction to be patched. For hardware breakpoints and watchpoints
+ // length specifies the memory region to be monitored. To avoid potential
+ // problems with duplicate packets, the operations should be implemented in
+ // an idempotent way.
- software_breakpoint_t bp;
bool insert = (packet[1] == 'Z');
std::vector<uint8_t>::const_iterator iter = packet.begin() + 2;
- int type = consume_hex_number(iter, packet.end());
+ gdb_breakpoint_type_t type = static_cast<gdb_breakpoint_type_t>(
+ consume_hex_number(iter, packet.end()));
if (*iter != ',')
return send_packet("E50");
iter++;
- bp.address = consume_hex_number(iter, packet.end());
+ reg_t address = consume_hex_number(iter, packet.end());
if (*iter != ',')
return send_packet("E51");
iter++;
- bp.size = consume_hex_number(iter, packet.end());
+ unsigned int size = consume_hex_number(iter, packet.end());
// There may be more options after a ; here, but we don't support that.
if (*iter != '#')
return send_packet("E52");
- if (type != 0) {
- // Only software breakpoints are supported.
- return send_packet("");
- }
-
- if (bp.size != 2 && bp.size != 4) {
- return send_packet("E53");
- }
-
- fence_i_required = true;
- add_operation(new collect_translation_info_op_t(*this, bp.address, bp.size));
- if (insert) {
- unsigned char* swbp = new unsigned char[4];
- if (bp.size == 2) {
- swbp[0] = C_EBREAK & 0xff;
- swbp[1] = (C_EBREAK >> 8) & 0xff;
- } else {
- swbp[0] = EBREAK & 0xff;
- swbp[1] = (EBREAK >> 8) & 0xff;
- swbp[2] = (EBREAK >> 16) & 0xff;
- swbp[3] = (EBREAK >> 24) & 0xff;
- }
+ switch (type) {
+ case GB_SOFTWARE:
+ if (size != 2 && size != 4) {
+ return send_packet("E53");
+ }
+ if (insert) {
+ software_breakpoint_insert(address, size);
+ } else {
+ software_breakpoint_remove(address, size);
+ }
+ break;
- breakpoints[bp.address] = new software_breakpoint_t(bp);
- add_operation(new memory_read_op_t(*this, bp.address, bp.size,
- breakpoints[bp.address]->instruction));
- add_operation(new memory_write_op_t(*this, bp.address, bp.size, swbp));
+ case GB_HARDWARE:
+ case GB_WRITE:
+ case GB_READ:
+ case GB_ACCESS:
+ {
+ hardware_breakpoint_t bp = {
+ .vaddr = address,
+ .size = size
+ };
+ bp.load = (type == GB_READ || type == GB_ACCESS);
+ bp.store = (type == GB_WRITE || type == GB_ACCESS);
+ bp.execute = (type == GB_HARDWARE || type == GB_ACCESS);
+ if (insert) {
+ hardware_breakpoint_insert(bp);
+ // Insert might fail if there's no space, so the insert operation will
+ // send its own OK (or not).
+ return;
+ } else {
+ hardware_breakpoint_remove(bp);
+ }
+ }
+ break;
- } else {
- software_breakpoint_t *found_bp;
- found_bp = breakpoints[bp.address];
- unsigned char* instruction = new unsigned char[4];
- memcpy(instruction, found_bp->instruction, 4);
- add_operation(new memory_write_op_t(*this, found_bp->address,
- found_bp->size, instruction));
- breakpoints.erase(bp.address);
- delete found_bp;
+ default:
+ return send_packet("E56");
}
return send_packet("OK");
void gdbserver_t::handle_packet(const std::vector<uint8_t> &packet)
{
if (compute_checksum(packet) != extract_checksum(packet)) {
- fprintf(stderr, "Received %ld-byte packet with invalid checksum\n", packet.size());
+ fprintf(stderr, "Received %zd-byte packet with invalid checksum\n", packet.size());
fprintf(stderr, "Computed checksum: %x\n", compute_checksum(packet));
print_packet(packet);
send("-");
return;
}
- D(fprintf(stderr, "Received %ld-byte packet from debug client: ", packet.size()));
+ D(fprintf(stderr, "Received %zd-byte packet from debug client: ", packet.size()));
D(print_packet(packet));
send("+");
}
}
+void gdbserver_t::send(uint8_t value)
+{
+ char buffer[3];
+ sprintf(buffer, "%02x", (int) value);
+ send(buffer);
+}
+
void gdbserver_t::send_packet(const char* data)
{
start_packet();