From 70543edbb8aff1778387a3ee3325b694a8e9ecca Mon Sep 17 00:00:00 2001
From: folkert van heusden <mail@vanheusden.com>
Date: Sun, 12 Jun 2022 15:46:43 +0200
Subject: [PATCH] debugger: mmudump

---
 bus.h        |  2 ++
 debugger.cpp | 43 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 45 insertions(+)

diff --git a/bus.h b/bus.h
index b9e2a13..eb50428 100644
--- a/bus.h
+++ b/bus.h
@@ -78,6 +78,8 @@ public:
 
 	uint16_t getMMR0() { return MMR0; }
 	uint16_t getMMR1() { return MMR1; }
+	uint16_t getMMR2() { return MMR2; }
+	uint16_t getMMR3() { return MMR3; }
 	void     clearMMR1();
 	void     addToMMR1(const int8_t delta, const uint8_t reg);
 	void     setMMR2(const uint16_t value) { MMR2 = value; }  // address
diff --git a/debugger.cpp b/debugger.cpp
index e441ec8..fdb8bc2 100644
--- a/debugger.cpp
+++ b/debugger.cpp
@@ -71,6 +71,43 @@ std::map<std::string, std::string> split(const std::vector<std::string> & kv_arr
 	return out;
 }
 
+void dump_par_pdr(console *const cnsl, bus *const b, const uint16_t pdrs, const uint16_t pars, const std::string & name, const int state)
+{
+	if (state == 0 || state == 2)
+		cnsl->put_string_lf(name);
+	else
+		cnsl->put_string_lf(format("%s DISABLED", name.c_str()));
+
+	cnsl->put_string_lf("   PAR             PDR");
+
+	for(int i=0; i<8; i++) {
+		uint16_t par_value = b->read(pars + i * 2, false, false, true);
+		uint16_t pdr_value = b->read(pdrs + i * 2, false, false, true);
+
+		uint16_t pdr_len   = (((pdr_value >> 8) & 127) + 1) * 64;
+
+		cnsl->put_string_lf(format("%d] %06o %08o %06o %04o D%d A%d", i, par_value, par_value * 64, pdr_value, pdr_len, !!(pdr_value & 8), pdr_value & 7));
+	}
+}
+
+void mmu_dump(console *const cnsl, bus *const b)
+{
+	uint16_t mmr0 = b->getMMR0();
+
+	cnsl->put_string_lf(mmr0 & 1 ? "MMU enabled" : "MMU NOT enabled");
+
+	uint16_t mmr3 = b->getMMR3();
+
+	dump_par_pdr(cnsl, b, 0172200, 0172240, "supervisor i-space", 0);
+	dump_par_pdr(cnsl, b, 0172220, 0172260, "supervisor d-space", 1 + (!!(mmr3 & 2)));
+
+	dump_par_pdr(cnsl, b, 0172300, 0172340, "kernel i-space", 0);
+	dump_par_pdr(cnsl, b, 0172320, 0172360, "kernel d-space", 1 + (!!(mmr3 & 4)));
+
+	dump_par_pdr(cnsl, b, 0177600, 0177640, "user i-space", 0);
+	dump_par_pdr(cnsl, b, 0177620, 0177660, "user d-space", 1 + (!!(mmr3 & 1)));
+}
+
 void debugger(console *const cnsl, bus *const b, std::atomic_uint32_t *const stop_event, const bool tracing_in)
 {
 	int32_t trace_start_addr = -1;
@@ -146,6 +183,11 @@ void debugger(console *const cnsl, bus *const b, std::atomic_uint32_t *const sto
 
 			continue;
 		}
+		else if (parts[0] == "mmudump") {
+			mmu_dump(cnsl, b);
+
+			continue;
+		}
 		else if (parts[0] == "strace") {
 			if (parts.size() != 2) {
 				trace_start_addr = -1;
@@ -206,6 +248,7 @@ void debugger(console *const cnsl, bus *const b, std::atomic_uint32_t *const sto
 			cnsl->put_string_lf("sbp/cbp/lbp   - set/clear/list breakpoint(s)");
 			cnsl->put_string_lf("trace/t       - toggle tracing");
 			cnsl->put_string_lf("strace        - start tracing from address - invoke without address to disable");
+			cnsl->put_string_lf("mmudump       - dump MMU settings (PARs/PDRs)");
 
 			continue;
 		}