Hi
Can I call CACHE_invL1d passing a big size? For example
(L1D is 32K)
CACHE_invL1d (addr, 7296, CACHE_WAIT)
CACHE_invL1d (addr, 32768, CACHE_WAIT)
I'm asking this because I have the following problem
2 Shared struct in MSCM, accessed by 8 cores, defined as follow
---------------------------------------------------
#pragma DATA_ALIGN (CACHE_L2_LINESIZE);
#pragma DATA_SECTION(".MSharedSram")
volatile Struct1 far gStruct1;
#pragma DATA_ALIGN (CACHE_L2_LINESIZE);
#pragma DATA_SECTION(".MSharedSram")
volatile Struct2 far gStruct2;
---------------------------------------------------
sizeof(Struct1) is 7284
sizeof(Struct2) is 32656
struct1 allocated at address 0x0C109880
struct2 allocated at address 0x0C10B500
both structs are accessed as follow (pseudo code)
{
while ((CSL_semAcquireDirect (HW_SEM)) == 0);
CACHE_invL1d ((void*)&x, sizeof(x), CACHE_WAIT);
x= x + 1;
CACHE_wbL1d ((void*)&x, sizeof(x), CACHE_WAIT);
CSL_semReleaseSemaphore (HW_SEM);
}
to access struct1 I use size 7296 (size multiple of the cache line size)
for example: CACHE_invL1d (addr, 7296, CACHE_WAIT)
to access struct2 I use size 32768, CACHE_invL1d (addr, 32768, CACHE_WAIT)
At regular interval (for debug, interval = 1 second), 8 cores read/write the structs:
- struct1 is always read correctly
- sometimes struct2 is accessed wrongly, that is, cores read back OLD values(There is a counter inside the struct, I see counter not incrementing correctly)
I found 2 workaround
Workaround1:
By DISABLING cache, program runs correctly for hours, to stress the program I set interval to 2 ms
Workaround2:
Cache ENABLED, I create a dummy struct of size 128 between struct1 and struct2 as follow
------------------------------------------------
#pragma DATA_ALIGN (CACHE_L2_LINESIZE);
#pragma DATA_SECTION(".MSharedSram")
volatile Struct1 far gStruct1;
#pragma DATA_ALIGN (CACHE_L2_LINESIZE);
#pragma DATA_SECTION(".MSharedSram")
volatile DummyStruct far gDummyStruct;
#pragma DATA_ALIGN (CACHE_L2_LINESIZE);
#pragma DATA_SECTION(".MSharedSram")
volatile Struct2 far gStruct2;
-----------------------------------------------
new address in memory are:
struct1 0x0C109880
dummyStruct 0x0C10B500
struct2 0x0C10B580
at startup I fill gDummyStruct with a know pattern, and at runtime I check that this struct is never overwritten
program runs correctly for hours, to stress the program I set interval to 2 ms
any idea????????
Thank you
Fabio
