Add new BIOS commands to play with MMU

fallen · Jun 6, 2012 · 2f35de4 · 2f35de4
1 parent 2bcd496
commit 2f35de4
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Showing 4 changed files with 123 additions and 15 deletions.
diff --git a/software/bios/dtlb_exception_handling_tests.c b/software/bios/dtlb_exception_handling_tests.c
@@ -51,7 +51,7 @@ void dtlb_exception_handling_tests() {
 	printf("\n<= Reading %d from virtual address 0x%08X\n\n", data, addr);
 
 	printf("=> Invalidating the mapping of virtual address 0x%08X in the TLB\n", addr);
-	mmu_dtlb_invalidate(addr);
+	mmu_dtlb_invalidate_line(addr);
 
 	data = 43;
 	printf("=> Writing %d to physical address 0x%08X\n", data, addr);
@@ -67,7 +67,7 @@ void dtlb_exception_handling_tests() {
 	check_for_error(ret);
 
 	printf("=> Invalidating the mapping of virtual address 0x%08X in the TLB\n", addr);
-	mmu_dtlb_invalidate(addr); // AND invalidate the mapping
+	mmu_dtlb_invalidate_line(addr); // AND invalidate the mapping
 
 	data = 44;
 	printf("=> Writting %d to physical address 0x%08X\n", data, addr+0x1000);

diff --git a/software/bios/main.c b/software/bios/main.c
@@ -422,6 +422,14 @@ static void help()
 	puts("version    - display version");
 	puts("reboot     - system reset");
 	puts("reconf     - reload FPGA configuration");
+	puts("dmap       - adds a MMU DTLB mapping");
+	puts("dunmap     - removes a MMU DTLB mapping");
+	puts("dtlbi      - invalidates the whole DTLB");
+	puts("dmapi      - invalidates a DTLB mapping");
+	puts("mmu        - activates MMU");
+	puts("nommu      - disactivates MMU");
+	puts("mmuread    - reads from memory with MMU enabled");
+	puts("mmuwrite   - writes to memory with MMU enabled");
 	puts("dtlbtest   - runs DTLB MMU load store tests");
 	puts("detest     - runs DTLB MMU exception handling tests");
 }
@@ -506,6 +514,75 @@ static void dtlbtest(void)
 
 }
 
+void mmuread(char *vaddr_str)
+{
+	unsigned int vaddr, data;
+	char *c;
+
+	vaddr = strtoul(vaddr_str, &c, 0);
+
+	data = read_word_with_mmu_enabled(vaddr);
+
+	printf("0x%08X contains 0x%08X\n", vaddr, data);
+}
+
+void mmuwrite(char *vaddr_str, char * data_str)
+{
+	unsigned int vaddr, data;
+	char *c;
+
+	vaddr = strtoul(vaddr_str, &c, 0);
+	data = strtoul(data_str, &c, 0);
+
+	write_word_with_mmu_enabled(vaddr, data);
+}
+
+void dmap(char *vaddr_str, char *paddr_str)
+{
+	unsigned int vaddr, paddr;
+	char *c;
+
+	vaddr = strtoul(vaddr_str, &c, 0);
+	paddr = strtoul(paddr_str, &c, 0);
+
+	mmu_map(vaddr, paddr);
+}
+
+void dunmap(char *vaddr_str)
+{
+	unsigned int vaddr;
+	char *c;
+
+	vaddr = strtoul(vaddr_str, &c, 0);
+
+	remove_mmu_mapping_for(vaddr);
+}
+
+void dtlbi(void)
+{
+	mmu_dtlb_invalidate();
+}
+
+void dmapi(char *vaddr_str)
+{
+	unsigned int vaddr;
+	char *c;
+
+	vaddr = strtoul(vaddr_str, &c, 0);
+
+	mmu_dtlb_invalidate_line(vaddr);
+}
+
+void activate_mmu(void)
+{
+	enable_dtlb();
+}
+
+void disactivate_mmu(void)
+{
+	disable_dtlb();
+}
+
 static void do_command(char *c)
 {
 	char *token;
@@ -540,7 +617,14 @@ static void do_command(char *c)
 	else if(strcmp(token, "wcsr") == 0) wcsr(get_token(&c), get_token(&c));
 	else if(strcmp(token, "dtlbtest") == 0) dtlbtest();
 	else if(strcmp(token, "detest") == 0) dtlb_exception_handling_tests();
-
+	else if(strcmp(token, "dmap") == 0) dmap(get_token(&c), get_token(&c));
+	else if(strcmp(token, "dunmap") == 0) dunmap(get_token(&c));
+	else if(strcmp(token, "dtlbi") == 0) dtlbi();
+	else if(strcmp(token, "mmu") == 0) activate_mmu();
+	else if(strcmp(token, "nommu") == 0) disactivate_mmu();
+	else if(strcmp(token, "mmuread") == 0) mmuread(get_token(&c));
+	else if(strcmp(token, "mmuwrite") == 0) mmuwrite(get_token(&c), get_token(&c));
+	else if(strcmp(token, "dmapi") == 0) dmapi(get_token(&c));
 	else if(strcmp(token, "") != 0)
 		printf("Command not found\n");
 }

diff --git a/software/include/hal/mmu.h b/software/include/hal/mmu.h
@@ -50,6 +50,7 @@ struct mmu_mapping {
 
 void mmu_dtlb_map(unsigned int vpfn, unsigned int pfn);
 unsigned int read_word_with_mmu_enabled(unsigned int vaddr);
-void mmu_dtlb_invalidate(unsigned int vaddr);
+void mmu_dtlb_invalidate_line(unsigned int vaddr);
+void mmu_dtlb_invalidate(void);
 
 #endif
diff --git a/software/libhal/mmu.c b/software/libhal/mmu.c
@@ -18,32 +18,43 @@
 #include <hal/mmu.h>
 #include <base/mmu.h>
 
+#define DTLB_CTRL_FLUSH_CMD	(0x3)
+#define DTLB_CTRL_DISABLE_CMD	(0x5)
+#define DTLB_CTRL_ENABLE_CMD	(0x9)
+
 /* @vpfn : virtual page frame number
  * @pfn  : physical page frame number
  */
 inline void mmu_dtlb_map(unsigned int vpfn, unsigned int pfn)
 {
 
 	asm volatile	("ori %0, %0, 1\n\t"
- 			 "wcsr tlbvaddr, %0"::"r"(vpfn):);
+ 			 "wcsr tlbvaddr, %0" :: "r"(vpfn) : );
 
 	asm volatile	("ori %0, %0, 1\n\t"
 			 "wcsr tlbpaddr, %0"::"r"(pfn):);
 
 	asm volatile	("xor r11, r11, r11\n\t"
 			 "ori r11, r11, 0x5\n\t"
-			 "wcsr tlbctrl, r11":::"r11");
+			 "wcsr tlbctrl, r11" ::: "r11");
 
 }
 
-inline void mmu_dtlb_invalidate(unsigned int vaddr)
+inline void mmu_dtlb_invalidate_line(unsigned int vaddr)
 {
 	asm volatile ("ori %0, %0, 1\n\t"
 		      "wcsr tlbvaddr, %0"::"r"(vaddr):);
 
 	asm volatile ("xor r11, r11, r11\n\t"
 		      "ori r11, r11, 0x21\n\t"
-		      "wcsr tlbctrl, r11":::"r11");
+		      "wcsr tlbctrl, r11" ::: "r11");
+}
+
+inline void mmu_dtlb_invalidate(void)
+{
+	register unsigned int cmd = DTLB_CTRL_FLUSH_CMD;
+	asm volatile("wcsr tlbctrl, %0" :: "r"(cmd) : );
+
 }
 
 /* This function activates the MMU
@@ -55,20 +66,32 @@ inline void mmu_dtlb_invalidate(unsigned int vaddr)
 
 unsigned int read_word_with_mmu_enabled(unsigned int vaddr)
 {
-	register unsigned int data;
+	register unsigned int data, cmd1, cmd2;
+
+	cmd1  = DTLB_CTRL_ENABLE_CMD;
+	cmd2 = DTLB_CTRL_DISABLE_CMD;
+
+	asm volatile("wcsr tlbctrl, %2\n\t" // Activates the MMU
+		     "xor r0, r0, r0\n\t"
+		     "lw  %0, (%1+0)\n\t" // Reads from virtual address "addr"
+		     "wcsr tlbctrl, %3\n\t" // Disactivates the MMU
+		     "xor r0, r0, r0\n\t" : "=&r"(data) : "r"(vaddr), "r"(cmd1), "r"(cmd2) : 
+	);
+
+	return data;
+}
+
+unsigned int write_word_with_mmu_enabled(register unsigned int vaddr, register unsigned int data)
+{
 	asm volatile(
 		"xor r11, r11, r11\n\t"
 		"ori r11, r11, 0x11\n\t"
 		"wcsr tlbctrl, r11\n\t" // Activates the MMU
 		"xor r0, r0, r0\n\t"
-		"xor r11, r11, r11\n\t"
-		"or r11, r11, %1\n\t"
-		"lw  %0, (r11+0)\n\t" // Reads from virtual address "addr"
+		"sw  (%0 + 0), %1\n\t" // Reads from virtual address "addr"
 		"xor r11, r11, r11\n\t"
 		"ori r11, r11, 0x9\n\t"
 		"wcsr tlbctrl, r11\n\t" // Disactivates the MMU
-		"xor r0, r0, r0\n\t" : "=&r"(data) : "r"(vaddr) : "r11"
+		"xor r0, r0, r0\n\t" :: "r"(vaddr), "r"(data) : "r11"
 	);
-
-	return data;
 }