Move peripherals to devices directory

- modify Makefile to enable detect devices directory - decouple PLIC and UART into separate files - Bind RISC-V core to plic_t to enable sending interrupt from PLIC to core
sysprog21 · Nov 2, 2024 · ee008f1 · ee008f1
1 parent cfb3c3a
commit ee008f1
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Showing 12 changed files with 150 additions and 87 deletions.
diff --git a/Makefile b/Makefile
@@ -47,8 +47,21 @@ OBJS_EXT :=
 
 ifeq ($(call has, SYSTEM), 1)
 OBJS_EXT += system.o
-OBJS_EXT += plic.o
-OBJS_EXT += uart.o
+endif
+
+ifeq ($(call has, GDBSTUB), 1)
+GDBSTUB_OUT = $(abspath $(OUT)/mini-gdbstub)
+GDBSTUB_COMM = 127.0.0.1:1234
+src/mini-gdbstub/Makefile:
+	git submodule update --init $(dir $@)
+GDBSTUB_LIB := $(GDBSTUB_OUT)/libgdbstub.a
+$(GDBSTUB_LIB): src/mini-gdbstub/Makefile
+	$(MAKE) -C $(dir $<) O=$(dir $@)
+OBJS_EXT += gdbstub.o breakpoint.o
+CFLAGS += -D'GDBSTUB_COMM="$(GDBSTUB_COMM)"'
+LDFLAGS += $(GDBSTUB_LIB) -pthread
+gdbstub-test: $(BIN)
+	$(Q).ci/gdbstub-test.sh && $(call notice, [OK])
 endif
 
 # Integer Multiplication and Division instructions
@@ -230,11 +243,22 @@ ifeq ($(call has, GDBSTUB), 1)
 $(OBJS): $(GDBSTUB_LIB)
 endif
 
+# Peripherals for system emulation
+ifeq ($(call has, SYSTEM), 1)
+DEV_OUT := $(OUT)/devices
+DEV_SRC := src/devices
+$(DEV_OUT)/%.o: $(DEV_SRC)/%.c $(deps_emcc)
+	$(VECHO) "  CC\t$@\n"
+	$(Q)$(CC) -o $@ $(CFLAGS) $(CFLAGS_emcc) -c -MMD -MF $@.d $<
+DEV_OBJS := $(patsubst $(DEV_SRC)/%.c, $(DEV_OUT)/%.o, $(wildcard $(DEV_SRC)/*.c))
+deps += $(DEV_OBJS:%.o=%.o.d)
+endif
+
 $(OUT)/%.o: src/%.c $(deps_emcc)
 	$(VECHO) "  CC\t$@\n"
 	$(Q)$(CC) -o $@ $(CFLAGS) $(CFLAGS_emcc) -c -MMD -MF $@.d $<
 
-$(BIN): $(OBJS)
+$(BIN): $(OBJS) $(DEV_OBJS)
 	$(VECHO) "  LD\t$@\n"
 	$(Q)$(CC) -o $@ $(CFLAGS_emcc) $^ $(LDFLAGS)
 
@@ -331,7 +355,7 @@ endif
 endif
 
 clean:
-	$(RM) $(BIN) $(OBJS) $(HIST_BIN) $(HIST_OBJS) $(deps) $(WEB_FILES) $(CACHE_OUT) src/rv32_jit.c
+	$(RM) $(BIN) $(OBJS) $(DEV_OBJS) $(HIST_BIN) $(HIST_OBJS) $(deps) $(WEB_FILES) $(CACHE_OUT) src/rv32_jit.c
 distclean: clean
 	-$(RM) $(DOOM_DATA) $(QUAKE_DATA)
 	$(RM) -r $(TIMIDITY_DATA)

diff --git a/src/plic.c → src/devices/plic.c b/src/plic.c → src/devices/plic.c
@@ -1,9 +1,18 @@
+/*
+ * rv32emu is freely redistributable under the MIT License. See the file
+ * "LICENSE" for information on usage and redistribution of this file.
+ */
+
+#include <assert.h>
+#include <stdlib.h>
+
 #include "plic.h"
+#include "../riscv.h"
+#include "../riscv_private.h"
 
-void plic_update_interrupts(riscv_t *rv)
+void plic_update_interrupts(plic_t *plic)
 {
-    vm_attr_t *attr = PRIV(rv);
-    plic_t *plic = attr->plic;
+    riscv_t *rv = (riscv_t *) plic->rv;
 
     /* Update pending interrupts */
     plic->ip |= plic->active & ~plic->masked;
@@ -15,11 +24,8 @@ void plic_update_interrupts(riscv_t *rv)
         rv->csr_sip &= ~SIP_SEIP;
 }
 
-uint32_t plic_read(riscv_t *rv, const uint32_t addr)
+uint32_t plic_read(plic_t *plic, const uint32_t addr)
 {
-    vm_attr_t *attr = PRIV(rv);
-    plic_t *plic = attr->plic;
-
     /* no priority support: source priority hardwired to 1 */
     if (1 <= addr && addr <= 31)
         return 0;
@@ -54,11 +60,8 @@ uint32_t plic_read(riscv_t *rv, const uint32_t addr)
     return plic_read_val;
 }
 
-void plic_write(riscv_t *rv, const uint32_t addr, uint32_t value)
+void plic_write(plic_t *plic, const uint32_t addr, uint32_t value)
 {
-    vm_attr_t *attr = PRIV(rv);
-    plic_t *plic = attr->plic;
-
     /* no priority support: source priority hardwired to 1 */
     if (1 <= addr && addr <= 31)
         return;
@@ -81,3 +84,11 @@ void plic_write(riscv_t *rv, const uint32_t addr, uint32_t value)
 
     return;
 }
+
+plic_t *plic_new()
+{
+    plic_t *plic = calloc(1, sizeof(plic_t));
+    assert(plic);
+
+    return plic;
+}
diff --git a/src/devices/plic.h b/src/devices/plic.h
@@ -0,0 +1,31 @@
+/*
+ * rv32emu is freely redistributable under the MIT License. See the file
+ * "LICENSE" for information on usage and redistribution of this file.
+ */
+
+#pragma once
+
+#include <stdint.h>
+
+/* PLIC */
+typedef struct {
+    uint32_t masked;
+    uint32_t ip;
+    uint32_t ie;
+    /* state of input interrupt lines (level-triggered), set by environment */
+    uint32_t active;
+    /* RISC-V instance to receive PLIC interrupt */
+    void *rv;
+} plic_t;
+
+/* update PLIC status */
+void plic_update_interrupts(plic_t *plic);
+
+/* read a word from PLIC */
+uint32_t plic_read(plic_t *plic, const uint32_t addr);
+
+/* write a word to PLIC */
+void plic_write(plic_t *plic, const uint32_t addr, uint32_t value);
+
+/* create a PLIC instance */
+plic_t *plic_new();
diff --git a/src/uart.c → src/devices/uart.c b/src/uart.c → src/devices/uart.c
@@ -1,14 +1,20 @@
+/*
+ * rv32emu is freely redistributable under the MIT License. See the file
+ * "LICENSE" for information on usage and redistribution of this file.
+ */
+
 #include <errno.h>
 #include <poll.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
-
-#include "io.h"
+#include <assert.h>
 
 /* Emulate 8250 (plain, without loopback mode support) */
 
+#include "uart.h"
+
 #define U8250_INT_THRE 1
 
 void u8250_update_interrupts(u8250_state_t *uart)
@@ -142,3 +148,11 @@ void u8250_write(u8250_state_t *uart, uint32_t addr, uint32_t value)
 {
     u8250_reg_write(uart, addr, value);
 }
+
+u8250_state_t *u8250_new()
+{
+    u8250_state_t *uart = calloc(1, sizeof(u8250_state_t));
+    assert(uart);
+
+    return uart;
+}
diff --git a/src/devices/uart.h b/src/devices/uart.h
@@ -0,0 +1,37 @@
+/*
+ * rv32emu is freely redistributable under the MIT License. See the file
+ * "LICENSE" for information on usage and redistribution of this file.
+ */
+
+#pragma once
+
+#include <stdbool.h>
+#include <stdint.h>
+
+#define IRQ_UART 1
+#define IRQ_UART_BIT (1 << IRQ_UART)
+
+typedef struct {
+    uint8_t dll, dlh;                  /* divisor (ignored) */
+    uint8_t lcr;                       /* UART config */
+    uint8_t ier;                       /* interrupt config */
+    uint8_t current_int, pending_ints; /* interrupt status */
+    uint8_t mcr;       /* other output signals, loopback mode (ignored) */
+    int in_fd, out_fd; /* I/O handling */
+    bool in_ready;
+} u8250_state_t;
+
+/* update UART status */
+void u8250_update_interrupts(u8250_state_t *uart);
+
+/* poll UART status */
+void u8250_check_ready(u8250_state_t *uart);
+
+/* read a word from UART */
+uint32_t u8250_read(u8250_state_t *uart, uint32_t addr);
+
+/* write a word to UART */
+void u8250_write(u8250_state_t *uart, uint32_t addr, uint32_t value);
+
+/* create a UART instance */
+u8250_state_t *u8250_new();
diff --git a/src/emulate.c b/src/emulate.c
@@ -10,10 +10,6 @@
 #include <stdlib.h>
 #include <string.h>
 
-#if RV32_HAS(SYSTEM)
-#include "plic.h"
-#endif /* RV32_HAS(SYSTEM) */
-
 #ifdef __EMSCRIPTEN__
 #include <emscripten.h>
 #endif

diff --git a/src/io.c b/src/io.c
@@ -15,22 +15,6 @@
 
 #include "io.h"
 
-u8250_state_t *u8250_new()
-{
-    u8250_state_t *uart = calloc(1, sizeof(u8250_state_t));
-    assert(uart);
-
-    return uart;
-}
-
-plic_t *plic_new()
-{
-    plic_t *plic = calloc(1, sizeof(plic_t));
-    assert(plic);
-
-    return plic;
-}
-
 static uint8_t *data_memory_base;
 
 memory_t *memory_new(uint32_t size)

diff --git a/src/io.h b/src/io.h
@@ -9,43 +9,7 @@
 #include <stdint.h>
 #include <string.h>
 
-/* UART */
-
-#define IRQ_UART 1
-#define IRQ_UART_BIT (1 << IRQ_UART)
-
-typedef struct {
-    uint8_t dll, dlh;                  /**< divisor (ignored) */
-    uint8_t lcr;                       /**< UART config */
-    uint8_t ier;                       /**< interrupt config */
-    uint8_t current_int, pending_ints; /**< interrupt status */
-    /* other output signals, loopback mode (ignored) */
-    uint8_t mcr;
-    /* I/O handling */
-    int in_fd, out_fd;
-    bool in_ready;
-} u8250_state_t;
-void u8250_update_interrupts(u8250_state_t *uart);
-void u8250_check_ready(u8250_state_t *uart);
-
-uint32_t u8250_read(u8250_state_t *uart, uint32_t addr);
-
-void u8250_write(u8250_state_t *uart, uint32_t addr, uint32_t value);
-
-/* create a UART controller */
-u8250_state_t *u8250_new();
-
-typedef struct {
-    uint32_t masked;
-    uint32_t ip;
-    uint32_t ie;
-    /* state of input interrupt lines (level-triggered), set by environment */
-    uint32_t active;
-} plic_t;
-
-/* create a PLIC core */
-plic_t *plic_new();
-
+/* main memory */
 typedef struct {
     uint8_t *mem_base;
     uint64_t mem_size;

diff --git a/src/plic.h b/src/plic.h
diff --git a/src/riscv.c b/src/riscv.c
@@ -367,6 +367,7 @@ riscv_t *rv_create(riscv_user_t rv_attr)
         /* setup PLIC */
         attr->plic = plic_new();
         assert(attr->plic);
+        attr->plic->rv = rv;
 
         /* setup PLIC */
         attr->uart = u8250_new();

diff --git a/src/riscv.h b/src/riscv.h
@@ -12,6 +12,11 @@
 #include "io.h"
 #include "map.h"
 
+#if RV32_HAS(SYSTEM)
+#include "devices/plic.h"
+#include "devices/uart.h"
+#endif /* RV32_HAS(EXT_SYSTEM) */
+
 #if RV32_HAS(EXT_F)
 #define float16_t softfloat_float16_t
 #define bfloat16_t softfloat_bfloat16_t
@@ -541,11 +546,13 @@ typedef struct {
 } vm_data_t;
 
 typedef struct {
+#if RV32_HAS(SYSTEM)
     /* uart object */
     u8250_state_t *uart;
 
     /* plic object */
     plic_t *plic;
+#endif /* RV32_HAS(SYSTEM) */
 
     /* vm memory object */
     memory_t *mem;

diff --git a/src/system.c b/src/system.c
@@ -7,7 +7,8 @@
 #error "Do not manage to build this file unless you enable system support."
 #endif
 
-#include "plic.h"
+#include "devices/plic.h"
+#include "devices/uart.h"
 #include "riscv_private.h"
 
 void emu_update_uart_interrupts(riscv_t *rv)
@@ -18,7 +19,7 @@ void emu_update_uart_interrupts(riscv_t *rv)
         attr->plic->active |= IRQ_UART_BIT;
     } else
         attr->plic->active &= ~IRQ_UART_BIT;
-    plic_update_interrupts(rv);
+    plic_update_interrupts(attr->plic);
 }
 
 #define MMIO_PLIC 1
@@ -31,11 +32,11 @@ uint8_t ret_char;
 #define MMIO_OP(io, rw)                                           \
     IIF(io)( /* PLIC */                                           \
         IIF(rw)( /* read */                                       \
-            read_val = plic_read(rv, (addr & 0x3FFFFFF) >> 2);           \
-	    plic_update_interrupts(rv); return read_val;          \
+            read_val = plic_read(PRIV(rv)->plic, (addr & 0x3FFFFFF) >> 2);           \
+	    plic_update_interrupts(PRIV(rv)->plic); return read_val;          \
 	    ,     /* write */                                     \
-            plic_write(rv, (addr & 0x3FFFFFF) >> 2, val);   \
-            plic_update_interrupts(rv); return;                   \
+            plic_write(PRIV(rv)->plic, (addr & 0x3FFFFFF) >> 2, val);   \
+            plic_update_interrupts(PRIV(rv)->plic); return;                   \
         )                                                         \
         ,    /* UART */                                           \
         IIF(rw)( /* read */                                       \