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authorred031000 <rubenru09@aol.com>2021-07-23 01:11:15 +0100
committerred031000 <rubenru09@aol.com>2021-07-23 01:12:27 +0100
commit5bf13c7f48fe91c7902ce50250bc1a5a2398a2ae (patch)
tree2e91e60bdb7a9174b16d8ca1b532809d4ae2e5b6 /arm9/lib/NitroSDK/src/OS_vramExclusive.c
parentc2d91a2d997afd01fa4f40e1e16d5ee85557c9a8 (diff)
separate out libs to libc, libnns and NitroSDK
Diffstat (limited to 'arm9/lib/NitroSDK/src/OS_vramExclusive.c')
-rw-r--r--arm9/lib/NitroSDK/src/OS_vramExclusive.c88
1 files changed, 88 insertions, 0 deletions
diff --git a/arm9/lib/NitroSDK/src/OS_vramExclusive.c b/arm9/lib/NitroSDK/src/OS_vramExclusive.c
new file mode 100644
index 00000000..5ce10f4a
--- /dev/null
+++ b/arm9/lib/NitroSDK/src/OS_vramExclusive.c
@@ -0,0 +1,88 @@
+#include "OS_vramExclusive.h"
+#include "function_target.h"
+#include "OS_system.h"
+
+static u32 OSi_vramExclusive;
+static u16 OSi_vramLockId[9];
+
+static u32 OsCountZeroBits(register u32 bitmap);
+
+ARM_FUNC static asm u32 OsCountZeroBits(register u32 bitmap)
+{
+ clz r0, r0
+ bx lr
+}
+
+ARM_FUNC void OSi_InitVramExclusive(void)
+{
+ OSi_vramExclusive = 0x0000;
+
+ for (s32 i = 0; i < 9; i++)
+ {
+ OSi_vramLockId[i] = 0;
+ }
+}
+
+ARM_FUNC BOOL OSi_TryLockVram(u16 bank, u16 lockId)
+{
+ u32 workMap;
+ s32 zeroBits;
+ OSIntrMode enabled = OS_DisableInterrupts();
+
+ workMap = (u32)(bank & OSi_vramExclusive);
+ while (TRUE)
+ {
+ zeroBits = (s32)(31 - OsCountZeroBits(workMap));
+ if (zeroBits < 0)
+ {
+ break;
+ }
+ workMap &= ~(0x00000001 << zeroBits);
+ if (OSi_vramLockId[zeroBits] != lockId)
+ {
+ (void)OS_RestoreInterrupts(enabled);
+ return FALSE;
+ }
+ }
+
+ workMap = (u32)(bank & 0x01ff);
+ while (TRUE)
+ {
+ zeroBits = (s32)(31 - OsCountZeroBits(workMap));
+ if (zeroBits < 0)
+ {
+ break;
+ }
+ workMap &= ~(0x00000001 << zeroBits);
+ OSi_vramLockId[zeroBits] = lockId;
+ OSi_vramExclusive |= (0x00000001 << zeroBits);
+ }
+
+ (void)OS_RestoreInterrupts(enabled);
+ return TRUE;
+}
+
+ARM_FUNC void OSi_UnlockVram(u16 bank, u16 lockId)
+{
+ u32 workMap;
+ s32 zeroBits;
+ OSIntrMode enabled = OS_DisableInterrupts();
+
+ workMap = (u32)(bank & OSi_vramExclusive & 0x01ff);
+ while (TRUE)
+ {
+ zeroBits = (s32)(31- OsCountZeroBits((u32)workMap));
+ if (zeroBits < 0)
+ {
+ break;
+ }
+ workMap &= ~(0x00000001 << zeroBits);
+ if (OSi_vramLockId[zeroBits] == lockId)
+ {
+ OSi_vramLockId[zeroBits] = 0;
+ OSi_vramExclusive &= ~(0x00000001 << zeroBits);
+ }
+ }
+
+ (void)OS_RestoreInterrupts(enabled);
+}