The cli()/sti() functions are not safe. We should have removed them long ago.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@4314 a1c6a512-1295-4272-9138-f99709370657

firmware/drivers/button.c

@@ -258,10 +258,11 @@ void button_set_flip(bool flip)
 {
     if (flip != flipped) /* not the curent setting */
     {
-        cli(); /* avoid race condition with the button_tick() */
+        /* avoid race condition with the button_tick() */
+        int oldlevel = set_irq_level(15);
         lastbtn = button_flip(lastbtn); 
         flipped = flip;
-        sti();
+        set_irq_level(oldlevel);
     }
 }
 

firmware/drivers/lcd.c

@@ -188,14 +188,16 @@ void lcd_write_data(unsigned char* p_bytes, int count)
 {
     do
     {
-        unsigned byte;
+        unsigned int byte;
-        unsigned sda1;     /* precalculated SC=low,SD=1 */
+        unsigned int sda1;     /* precalculated SC=low,SD=1 */
-        unsigned clk0sda0; /* precalculated SC and SD low */
+        unsigned int clk0sda0; /* precalculated SC and SD low */
+        unsigned int oldlevel;
 
         byte = *p_bytes++ << 24; /* fetch to MSB position */
 
-        cli();  /* make port modifications atomic, in case an IRQ uses PBDRL */
+        /* make port modifications atomic, in case an IRQ uses PBDRL */
         /* (currently not the case, so this could be optimized away) */
+        oldlevel = set_irq_level(15);
 
         /* precalculate the values for later bit toggling, init data write */
         asm (
@@ -285,7 +287,7 @@ void lcd_write_data(unsigned char* p_bytes, int count)
             : "r0"
         );
 
-        sti();
+        set_irq_level(oldlevel);
 
     } while (--count); /* tail loop is faster */
 }
@@ -298,13 +300,15 @@ void lcd_write_data(unsigned char* p_bytes, int count)
     {
         unsigned byte;
         unsigned sda1;     /* precalculated SC=low,SD=1 */
+        unsigned int oldlevel;
 
         /* take inverse data, so I can use the NEGC instruction below, it is
            the only carry add/sub which does not destroy a source register */
         byte = ~(*p_bytes++ << 24); /* fetch to MSB position */
 
-        cli(); /* make port modifications atomic, in case an IRQ uses PBDRL */
+        /* make port modifications atomic, in case an IRQ uses PBDRL */
         /* (currently not the case, so this could be optimized away) */
+        oldlevel = set_irq_level(15);
 
         /* precalculate the values for later bit toggling, init data write */
         asm (
@@ -386,7 +390,7 @@ void lcd_write_data(unsigned char* p_bytes, int count)
             "r0"
         );
 
-        sti(); /* end of atomic port modifications */
+        set_irq_level(oldlevel);
 
     } while (--count); /* tail loop is faster */
 }

firmware/export/kernel.h

@@ -64,7 +64,6 @@ extern long current_tick;
 extern void kernel_init(void);
 extern void yield(void);
 extern void sleep(int ticks);
-int set_irq_level(int level);
 int tick_add_task(void (*f)(void));
 int tick_remove_task(void (*f)(void));
 

firmware/export/system.h

@@ -23,6 +23,10 @@
 #include "sh7034.h"
 #include "config.h"
 
+extern void system_reboot (void);
+extern void system_init(void);
+extern int set_irq_level(int level);
+
 #define FREQ CPU_FREQ
 #define BAUDRATE 9600
 
@@ -113,47 +117,34 @@ static inline int tas (volatile int *pointer)
     return result;
   }
 
-static inline void sti (void)
-  {
-    asm volatile ("ldc\t%0,sr" : : "r"(0<<4));
-  }
-
-static inline void cli (void)
-  {
-    asm volatile ("ldc\t%0,sr" : : "r"(15<<4));
-  }
-
 /* Compare And Swap */
 static inline int cas (volatile int *pointer,int requested_value,int new_value)
   {
-    cli();
+    unsigned int oldlevel = set_irq_level(15);
     if (*pointer == requested_value)
       {
         *pointer = new_value;
-        sti ();
+        set_irq_level(oldlevel);
         return 1;
       }
-    sti ();
+    set_irq_level(oldlevel);
     return 0;
   }
 
 static inline int cas2 (volatile int *pointer1,volatile int *pointer2,int requested_value1,int requested_value2,int new_value1,int new_value2)
   {
-    cli();
+    unsigned int oldlevel = set_irq_level(15);
     if (*pointer1 == requested_value1 && *pointer2 == requested_value2)
       {
         *pointer1 = new_value1;
         *pointer2 = new_value2;
-        sti ();
+        set_irq_level(oldlevel);
         return 1;
       }
-    sti ();
+    set_irq_level(oldlevel);
     return 0;
   }
 
 #endif
 
-extern void system_reboot (void);
-extern void system_init(void);
-
 #endif

firmware/kernel.c

@@ -70,18 +70,6 @@ void yield(void)
     wake_up_thread();
 }
 
-/****************************************************************************
- * Interrupt level setting
- ****************************************************************************/
-int set_irq_level(int level)
-{
-    int i;
-    /* Read the old level and set the new one */
-    asm volatile ("stc sr, %0" : "=r" (i));
-    asm volatile ("ldc %0, sr" : : "r" (level << 4));
-    return (i >> 4) & 0x0f;
-}
-
 /****************************************************************************
  * Queue handling stuff
  ****************************************************************************/

firmware/system.c

@@ -302,7 +302,7 @@ void (*vbr[]) (void) __attribute__ ((section (".vectors"))) =
 
 void system_reboot (void)
 {
-    cli ();
+    set_irq_level(15);
 
     asm volatile ("ldc\t%0,vbr" : : "r"(0));
 
@@ -318,6 +318,18 @@ void system_reboot (void)
 		  "r"(*(int*)0),"r"(4));
 }
 
+/****************************************************************************
+ * Interrupt level setting
+ ****************************************************************************/
+int set_irq_level(int level)
+{
+    int i;
+    /* Read the old level and set the new one */
+    asm volatile ("stc sr, %0" : "=r" (i));
+    asm volatile ("ldc %0, sr" : : "r" (level << 4));
+    return (i >> 4) & 0x0f;
+}
+
 void UIE (unsigned int pc) /* Unexpected Interrupt or Exception */
 {
     bool state = true;