Remove mtime/mtimecmp

machine/configstring.c

@@ -170,20 +170,30 @@ static void query_mem(const char* config_string)
   mem_size = get_uint(res);
 }
 
+static void query_rtc(const char* config_string)
+{
+  query_result res = query_config_string(config_string, "rtc{addr");
+  assert(res.start);
+  mtime = (void*)get_uint(res);
+}
+
 static void query_harts(const char* config_string)
 {
   for (int core = 0, hart; ; core++) {
     for (hart = 0; ; hart++) {
       char buf[32];
-      snprintf(buf, sizeof buf, "core{%d{%d{addr", core, hart);
+      snprintf(buf, sizeof buf, "core{%d{%d{isa", core, hart);
       query_result res = query_config_string(config_string, buf);
       if (!res.start)
         break;
-      csr_t* base = (csr_t*)get_uint(res);
-      uintptr_t hart_id = base[CSR_MHARTID];
-      hls_init(hart_id, base);
+      hls_t* hls = hls_init(num_harts);
+
+      snprintf(buf, sizeof buf, "core{%d{%d{timecmp", core, hart);
+      res = query_config_string(config_string, buf);
+      assert(res.start);
+      hls->timecmp = (void*)get_uint(res);
+
       num_harts++;
-      assert(hart_id == num_harts-1);
     }
     if (!hart)
       break;
@@ -196,5 +206,6 @@ void parse_config_string()
 {
   const char* s = (const char*)read_csr(mcfgaddr);
   query_mem(s);
+  query_rtc(s);
   query_harts(s);
 }

machine/emulation.c

@@ -91,7 +91,7 @@ static inline int emulate_read_csr(int num, uintptr_t mstatus, uintptr_t* result
   switch (num)
   {
     case CSR_TIME:
-      *result = read_csr(mtime) + HLS()->utime_delta;
+      *result = *mtime + HLS()->utime_delta;
       return 0;
     case CSR_CYCLE:
       *result = read_csr(mcycle) + HLS()->ucycle_delta;
@@ -100,7 +100,7 @@ static inline int emulate_read_csr(int num, uintptr_t mstatus, uintptr_t* result
       *result = read_csr(minstret) + HLS()->uinstret_delta;
       return 0;
     case CSR_STIME:
-      *result = read_csr(mtime) + HLS()->stime_delta;
+      *result = *mtime + HLS()->stime_delta;
       return 0;
     case CSR_SCYCLE:
       *result = read_csr(mcycle) + HLS()->scycle_delta;
@@ -110,8 +110,7 @@ static inline int emulate_read_csr(int num, uintptr_t mstatus, uintptr_t* result
       return 0;
 #ifdef __riscv32
     case CSR_TIMEH:
-      *result = (((uint64_t)read_csr(mtimeh) << 32) + read_csr(mtime)
-                 + HLS()->stime_delta) >> 32;
+      *result = (*mtime + HLS()->stime_delta) >> 32;
       return 0;
     case CSR_CYCLEH:
       *result = (((uint64_t)read_csr(mcycleh) << 32) + read_csr(mcycle)

machine/encoding.h

@@ -647,7 +647,6 @@
 #define CSR_MIDELEG 0x303
 #define CSR_MIE 0x304
 #define CSR_MTVEC 0x305
-#define CSR_MTIMECMP 0x321
 #define CSR_MSCRATCH 0x340
 #define CSR_MEPC 0x341
 #define CSR_MCAUSE 0x342
@@ -663,7 +662,6 @@
 #define CSR_MSTIME_DELTA 0x705
 #define CSR_MSINSTRET_DELTA 0x706
 #define CSR_MCYCLE 0xf00
-#define CSR_MTIME 0xf01
 #define CSR_MINSTRET 0xf02
 #define CSR_MISA 0xf10
 #define CSR_MVENDORID 0xf11
@@ -677,7 +675,6 @@
 #define CSR_CYCLEH 0xc80
 #define CSR_TIMEH 0xc81
 #define CSR_INSTRETH 0xc82
-#define CSR_MTIMECMPH 0x361
 #define CSR_MUCYCLE_DELTAH 0x780
 #define CSR_MUTIME_DELTAH 0x781
 #define CSR_MUINSTRET_DELTAH 0x782
@@ -685,7 +682,6 @@
 #define CSR_MSTIME_DELTAH 0x785
 #define CSR_MSINSTRET_DELTAH 0x786
 #define CSR_MCYCLEH 0xf80
-#define CSR_MTIMEH 0xf81
 #define CSR_MINSTRETH 0xf82
 #define CAUSE_MISALIGNED_FETCH 0x0
 #define CAUSE_FAULT_FETCH 0x1
@@ -952,7 +948,6 @@ DECLARE_CSR(medeleg, CSR_MEDELEG)
 DECLARE_CSR(mideleg, CSR_MIDELEG)
 DECLARE_CSR(mie, CSR_MIE)
 DECLARE_CSR(mtvec, CSR_MTVEC)
-DECLARE_CSR(mtimecmp, CSR_MTIMECMP)
 DECLARE_CSR(mscratch, CSR_MSCRATCH)
 DECLARE_CSR(mepc, CSR_MEPC)
 DECLARE_CSR(mcause, CSR_MCAUSE)
@@ -968,7 +963,6 @@ DECLARE_CSR(mscycle_delta, CSR_MSCYCLE_DELTA)
 DECLARE_CSR(mstime_delta, CSR_MSTIME_DELTA)
 DECLARE_CSR(msinstret_delta, CSR_MSINSTRET_DELTA)
 DECLARE_CSR(mcycle, CSR_MCYCLE)
-DECLARE_CSR(mtime, CSR_MTIME)
 DECLARE_CSR(minstret, CSR_MINSTRET)
 DECLARE_CSR(misa, CSR_MISA)
 DECLARE_CSR(mvendorid, CSR_MVENDORID)
@@ -982,7 +976,6 @@ DECLARE_CSR(mreset, CSR_MRESET)
 DECLARE_CSR(cycleh, CSR_CYCLEH)
 DECLARE_CSR(timeh, CSR_TIMEH)
 DECLARE_CSR(instreth, CSR_INSTRETH)
-DECLARE_CSR(mtimecmph, CSR_MTIMECMPH)
 DECLARE_CSR(mucycle_deltah, CSR_MUCYCLE_DELTAH)
 DECLARE_CSR(mutime_deltah, CSR_MUTIME_DELTAH)
 DECLARE_CSR(muinstret_deltah, CSR_MUINSTRET_DELTAH)
@@ -990,7 +983,6 @@ DECLARE_CSR(mscycle_deltah, CSR_MSCYCLE_DELTAH)
 DECLARE_CSR(mstime_deltah, CSR_MSTIME_DELTAH)
 DECLARE_CSR(msinstret_deltah, CSR_MSINSTRET_DELTAH)
 DECLARE_CSR(mcycleh, CSR_MCYCLEH)
-DECLARE_CSR(mtimeh, CSR_MTIMEH)
 DECLARE_CSR(minstreth, CSR_MINSTRETH)
 #endif
 #ifdef DECLARE_CAUSE

machine/minit.c

@@ -8,6 +8,7 @@ pte_t* root_page_table;
 uintptr_t first_free_paddr;
 uintptr_t mem_size;
 uintptr_t num_harts;
+volatile uint64_t* mtime;
 
 static void mstatus_init()
 {
@@ -62,11 +63,11 @@ static void fp_init()
 #endif
 }
 
-void hls_init(uintptr_t id, csr_t* csrs)
+hls_t* hls_init(uintptr_t id)
 {
   hls_t* hls = OTHER_HLS(id);
   memset(hls, 0, sizeof(*hls));
-  hls->csrs = csrs;
+  return hls;
 }
 
 static uintptr_t sbi_top_paddr()
@@ -91,7 +92,7 @@ static void hart_init()
 void init_first_hart()
 {
   hart_init();
-  hls_init(0, NULL); // this might get called again from parse_config_string
+  hls_init(0); // this might get called again from parse_config_string
   parse_config_string();
   memory_init();
   boot_loader();
@@ -102,7 +103,7 @@ void init_other_hart()
   hart_init();
 
   // wait until hart 0 discovers us
-  while (*(csr_t * volatile *)&HLS()->csrs == NULL)
+  while (*(uint64_t * volatile *)&HLS()->timecmp == NULL)
     ;
 
   boot_other_hart();

machine/mtrap.c

@@ -91,7 +91,8 @@ static void send_ipi(uintptr_t recipient, int event)
 {
   if ((atomic_or(&OTHER_HLS(recipient)->mipi_pending, event) & event) == 0) {
     mb();
-    OTHER_HLS(recipient)->csrs[CSR_MIPI] = 1;
+    if (recipient != read_const_csr(mhartid))
+      assert(!"IPIs temporarily missing");
   }
 }
 
@@ -136,12 +137,7 @@ static uintptr_t mcall_shutdown()
 
 static uintptr_t mcall_set_timer(uint64_t when)
 {
-  // bbl/pk don't use the timer, so there's no need to virtualize it
-#ifdef __riscv32
-  write_csr(mtimecmp, -1);
-  write_csr(mtimecmph, (uintptr_t)(when >> 32));
-#endif
-  write_csr(mtimecmp, (uintptr_t)when);
+  *HLS()->timecmp = when;
   clear_csr(mip, MIP_STIP);
   set_csr(mie, MIP_MTIP);
   return 0;

machine/mtrap.h

@@ -31,11 +31,10 @@ static inline int xlen()
 extern uintptr_t first_free_paddr;
 extern uintptr_t mem_size;
 extern uintptr_t num_harts;
-
-typedef uintptr_t csr_t; // TODO this might become uint128_t for RV128
+extern volatile uint64_t* mtime;
 
 typedef struct {
-  volatile csr_t* csrs;
+  uint64_t* timecmp;
   volatile int mipi_pending;
   volatile int sipi_pending;
   int console_ibuf;
@@ -60,7 +59,7 @@ typedef struct {
 #define HLS() ((hls_t*)(MACHINE_STACK_TOP() - HLS_SIZE))
 #define OTHER_HLS(id) ((hls_t*)((void*)HLS() + RISCV_PGSIZE * ((id) - read_const_csr(mhartid))))
 
-void hls_init(uintptr_t hart_id, csr_t* csrs);
+hls_t* hls_init(uintptr_t hart_id);
 void parse_config_string();
 void poweroff(void) __attribute((noreturn));
 void printm(const char* s, ...);