module ti.sysbios.family.arm.a8.Cache
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ARM Cache Module

This module manages the data and instruction caches on Cortex A8 processors. It provides a list of functions that perform cache operations. The functions operate on a per cache line except for the 'All' functions which operate on the entire cache specified. Any Address that is not aligned to a cache line gets rounded down to the address of the nearest cache line. [ more ... ]
C synopsis target-domain sourced in ti/sysbios/family/arm/a8/Cache.xdc
#include <ti/sysbios/family/arm/a8/Cache.h>
Functions
Void 
Cache_disableBP// Disable Branch Prediction();
Void 
Cache_enableBP// Enable Branch Prediction();
Void 
Cache_invL1dAll// Invalidate all of L1 data cache();
Void 
Cache_invL1pAll// Invalidate all of L1 program cache();
UInt 
Cache_lock// Loads and locks a memory block into the L2 cache(Ptr blockPtr, SizeT byteCnt);
Void 
Cache_unlock// Unlocks an L2 cache way(UInt key);
Functions common to all ICache modules
Void 
Cache_disable// Disables the 'type' cache(s)(Bits16 type);
Void 
Cache_enable// Enables all cache(s)(Bits16 type);
Void 
Cache_inv// Invalidate the range of memory within the specified starting address and byte count. The range of addresses operated on gets quantized to whole cache lines in each cache. All lines in range are invalidated for all the 'type' caches(Ptr blockPtr, SizeT byteCnt, Bits16 type, Bool wait);
Void 
Cache_wait// Wait for a previous cache operation to complete();
Void 
Cache_wb// Writes back a range of memory from all cache(s)(Ptr blockPtr, SizeT byteCnt, Bits16 type, Bool wait);
Void 
Cache_wbAll// Write back all caches();
Void 
Cache_wbInv// Writes back and invalidates the range of memory within the specified starting address and byte count. The range of addresses operated on gets quantized to whole cache lines in each cache. All lines within the range are written back to the source memory and then invalidated for all 'type' caches(Ptr blockPtr, SizeT byteCnt, Bits16 type, Bool wait);
Void 
Cache_wbInvAll// Write back invalidate all caches();
Functions common to all target modules
Cache_Module_getMask// Returns the diagnostics mask for this module, Cache_Module_hasMask// Test whether this module has a diagnostics mask, Cache_Module_heap// The heap from which this module allocates memory, Cache_Module_id// Get this module's unique id, Cache_Module_setMask// Set the diagnostics mask for this module, Cache_Module_startupDone// Test if this module has completed startup
Defines
#define
Cache_sizeL1dCacheLine// Size of L1 data cache Line (UInt)64
#define
Cache_sizeL1pCacheLine// Size of L1 program cache Line (UInt)64
#define
Cache_sizeL2CacheLine// Size of L2 cache Line (UInt)64
Typedefs
typedef enum
Cache_Type// Lists of bitmask cache types ...
Constants
extern const Assert_Id 
Cache_A_badBlockLength// Asserted in Cache_lock;
extern const Assert_Id 
Cache_A_blockCrossesPage// Asserted in Cache_lock;
extern const Bool 
Cache_branchPredictionEnabled// Enable Branch Prediction at startup, default is true;
extern const Bool 
Cache_enableCache// Enable L1 and L2 data and program caches;
extern const Bool 
Cache_unlockL2Cache// Unlock all 8 L2 cache ways at startup, default is true;
 
DETAILS
This module manages the data and instruction caches on Cortex A8 processors. It provides a list of functions that perform cache operations. The functions operate on a per cache line except for the 'All' functions which operate on the entire cache specified. Any Address that is not aligned to a cache line gets rounded down to the address of the nearest cache line.
The L1 data and program caches as well as the L2 cache are enabled by default early during the startup sequence (prior to any Module_startup()s). Data caching requires the MMU to be enabled and the cacheable attribute of the section/page descriptor for a corresponding memory region to be enabled. Program caching does not require the MMU to be enabled and therefore occurs when the L1 program cache is enabled.
Note: See the ti.sysbios.family.arm.a8.Mmu module for information about the MMU.
Unconstrained Functions All functions

Calling Context

Function Hwi Swi Task Main Startup
disable Y Y Y Y Y
enable Y Y Y Y Y
inv Y Y Y Y Y
invL1dAll Y Y Y Y Y
invL1pAll Y Y Y Y Y
wait Y Y Y Y Y
wb Y Y Y Y Y
wbInv Y Y Y Y Y
wbInvL1dAll Y Y Y Y Y
wbL1dAll Y Y Y Y Y
lock Y Y Y Y Y
unlock Y Y Y Y Y
Definitions:
  • Hwi: API is callable from a Hwi thread.
  • Swi: API is callable from a Swi thread.
  • Task: API is callable from a Task thread.
  • Main: API is callable during any of these phases:
    • In your module startup after this module is started (e.g. Cache_Module_startupDone() returns TRUE).
    • During xdc.runtime.Startup.lastFxns.
    • During main().
    • During BIOS.startupFxns.
  • Startup: API is callable during any of these phases:
    • During xdc.runtime.Startup.firstFxns.
    • In your module startup before this module is started (e.g. Cache_Module_startupDone() returns FALSE).
 
const Cache_sizeL1dCacheLine
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Size of L1 data cache Line

C synopsis target-domain
#define Cache_sizeL1dCacheLine (UInt)64
 
 
const Cache_sizeL1pCacheLine
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Size of L1 program cache Line

C synopsis target-domain
#define Cache_sizeL1pCacheLine (UInt)64
 
 
const Cache_sizeL2CacheLine
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Size of L2 cache Line

C synopsis target-domain
#define Cache_sizeL2CacheLine (UInt)64
 
 
enum Cache_Type
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Lists of bitmask cache types

C synopsis target-domain
typedef enum Cache_Type {
    Cache_Type_L1P,
    // Level 1 Program cache
    Cache_Type_L1D,
    // Level 1 Data cache
    Cache_Type_L1,
    // Level 1 caches
    Cache_Type_L2P,
    // Level 2 Program cache
    Cache_Type_L2D,
    // Level 2 Data cache
    Cache_Type_L2,
    // Level 2 caches
    Cache_Type_ALLP,
    // All Program caches
    Cache_Type_ALLD,
    // All Data caches
    Cache_Type_ALL
    // All caches
} Cache_Type;
 
 
config Cache_A_badBlockLength  // module-wide
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Asserted in Cache_lock

C synopsis target-domain
extern const Assert_Id Cache_A_badBlockLength;
 
 
config Cache_A_blockCrossesPage  // module-wide
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Asserted in Cache_lock

C synopsis target-domain
extern const Assert_Id Cache_A_blockCrossesPage;
 
 
config Cache_branchPredictionEnabled  // module-wide
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Enable Branch Prediction at startup, default is true

C synopsis target-domain
extern const Bool Cache_branchPredictionEnabled;
 
DETAILS
This flag controls whether Branch Prediction should be automatically enabled or disabled during system startup.
NOTE
Upon reset, the A8's Program Flow Prediction (Branch Prediction) feature is disabled.
 
config Cache_enableCache  // module-wide
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Enable L1 and L2 data and program caches

C synopsis target-domain
extern const Bool Cache_enableCache;
 
DETAILS
To enable a subset of the caches, set this parameter to 'false' and call Cache_enable() within main, passing it only the Cache_Type(s) to be enabled.
Data caching requires the MMU and the memory section/page descriptor cacheable attribute to be enabled.
 
config Cache_unlockL2Cache  // module-wide
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Unlock all 8 L2 cache ways at startup, default is true

C synopsis target-domain
extern const Bool Cache_unlockL2Cache;
 
DETAILS
Ordinarily, the L2 cache ways should all be unlocked at system startup.
During development using CCS, if the application exits while L2 cache ways are locked, the soft-reset function DOES NOT unlock the L2 cache ways. To overcome this problem, the L2 cache ways are unlocked during Cache module startup.
If for any reason this behavior is undesirable, setting this config parameter to false will disable the automatic unlocking of the L2 cache ways.
 
Cache_disable()  // module-wide
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Disables the 'type' cache(s)

C synopsis target-domain
Void Cache_disable(Bits16 type);
 
ARGUMENTS
type — bit mask of Cache type
 
Cache_disableBP()  // module-wide
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Disable Branch Prediction

C synopsis target-domain
Void Cache_disableBP();
 
DETAILS
Calling this API will disable branch prediction.
NOTE
Upon reset, the A8's Program Flow Prediction (Branch Prediction) feature is disabled.
 
Cache_enable()  // module-wide
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Enables all cache(s)

C synopsis target-domain
Void Cache_enable(Bits16 type);
 
ARGUMENTS
type — bit mask of Cache type
 
Cache_enableBP()  // module-wide
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Enable Branch Prediction

C synopsis target-domain
Void Cache_enableBP();
 
DETAILS
Calling this API will enable branch prediction.
NOTE
Upon reset, the A8's Program Flow Prediction (Branch Prediction) feature is disabled.
 
Cache_inv()  // module-wide
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Invalidate the range of memory within the specified starting address and byte count. The range of addresses operated on gets quantized to whole cache lines in each cache. All lines in range are invalidated for all the 'type' caches

C synopsis target-domain
Void Cache_inv(Ptr blockPtr, SizeT byteCnt, Bits16 type, Bool wait);
 
ARGUMENTS
blockPtr — start address of range to be invalidated
byteCnt — number of bytes to be invalidated
type — bit mask of Cache type
wait — wait until the operation is completed
 
Cache_invL1dAll()  // module-wide
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Invalidate all of L1 data cache

C synopsis target-domain
Void Cache_invL1dAll();
 
DETAILS
This function should be used with caution. In general, the L1 data cache may contain some stack variable or valid data that should not be invalidated. This function should be used only when all contents of L1 data cache is unwanted.
 
Cache_invL1pAll()  // module-wide
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Invalidate all of L1 program cache

C synopsis target-domain
Void Cache_invL1pAll();
 
 
Cache_lock()  // module-wide
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Loads and locks a memory block into the L2 cache

C synopsis target-domain
UInt Cache_lock(Ptr blockPtr, SizeT byteCnt);
 
ARGUMENTS
blockPtr — start address of range to be locked
byteCnt — number of bytes to be locked
RETURNS
key = bitmask of L2 cache "way" used
DETAILS
A block of memory is loaded into the L2 cache and a corresponding L2 cache "way" is locked.
The memory block is loaded into cache one L2 cache line at time.
The returned key is a bitmask of the L2 cache "way" used to lock the memory block. This key should be passed in a subsequent call to Cache_unlock() if the memory block is to be unlocked.
If the key returned is zero, then the lock operation failed due to insufficient cache "ways" remaining to perform the operation. The locking algorithm requires at least two unlocked cache ways: one for the memory block, and one for the locking code itself.
As the A8 L2 cache is always an 8 way cache, locking a cache way consumes 1/8 of the total L2 cache, regardless of the actual memory block size. For instance, if the size of L2 cache is 256K bytes, locking ANY size memory block into a way will tie up 32K bytes of L2 cache.
The byteCnt argument must be less than or equal to an L2 "way" size. Locking memory blocks larger than a way page size requires calling this API multiple times. An assert is generated if this rule is violated.
The memory block must not cross an L2 "way" page boundary. Locking memory blocks that cross way page boundaries requires calling this API multiple times. An assert is generated if this rule is violated.
Except for the normal L1 instruction cache behavior during code execution, the L1 instruction cache is unaffected by this API. The L1 data cache will be temporarily polluted by the contents of the referenced memory block.
NOTE
Interrupts are disabled for the entire time the memory block is being loaded into cache. For this reason, use of this API is probably best at system intialization time (ie: within 'main()').
 
Cache_unlock()  // module-wide
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Unlocks an L2 cache way

C synopsis target-domain
Void Cache_unlock(UInt key);
 
ARGUMENTS
key — key returned by lock.
DETAILS
Unlocks the L2 cache "way" locked by Cache_lock().
NOTE
multiple L2 cache "ways" can be unlocked simultaneously by "or-ing" together the bitmasks returned from several invocations of Cache_lock().
 
Cache_wait()  // module-wide
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Wait for a previous cache operation to complete

C synopsis target-domain
Void Cache_wait();
 
DETAILS
Wait for the cache wb/wbInv/inv operation to complete. A cache operation is not truly complete until it has worked its way through all buffering and all memory writes have landed in the source memory.
 
Cache_wb()  // module-wide
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Writes back a range of memory from all cache(s)

C synopsis target-domain
Void Cache_wb(Ptr blockPtr, SizeT byteCnt, Bits16 type, Bool wait);
 
ARGUMENTS
blockPtr — start address of range to be invalidated
byteCnt — number of bytes to be invalidated
type — bit mask of Cache type
wait — wait until the operation is completed
DETAILS
Writes back the range of memory within the specified starting address and byte count. The range of addresses operated on gets quantized to whole cache lines in each cache. All lines within the range are left valid in the 'type' caches and the data within the range will be written back to the source memory.
 
Cache_wbAll()  // module-wide
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Write back all caches

C synopsis target-domain
Void Cache_wbAll();
 
DETAILS
Perform a global write back. There is no effect on program cache. All data cache lines are left valid.
 
Cache_wbInv()  // module-wide
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Writes back and invalidates the range of memory within the specified starting address and byte count. The range of addresses operated on gets quantized to whole cache lines in each cache. All lines within the range are written back to the source memory and then invalidated for all 'type' caches

C synopsis target-domain
Void Cache_wbInv(Ptr blockPtr, SizeT byteCnt, Bits16 type, Bool wait);
 
ARGUMENTS
blockPtr — start address of range to be invalidated
byteCnt — number of bytes to be invalidated
type — bit mask of Cache type
wait — wait until the operation is completed
 
Cache_wbInvAll()  // module-wide
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Write back invalidate all caches

C synopsis target-domain
Void Cache_wbInvAll();
 
DETAILS
Performs a global write back and invalidate. All cache lines are written out to physical memory and then invalidated.
Module-Wide Built-Ins
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C synopsis target-domain
Types_ModuleId Cache_Module_id();
// Get this module's unique id
 
Bool Cache_Module_startupDone();
// Test if this module has completed startup
 
IHeap_Handle Cache_Module_heap();
// The heap from which this module allocates memory
 
Bool Cache_Module_hasMask();
// Test whether this module has a diagnostics mask
 
Bits16 Cache_Module_getMask();
// Returns the diagnostics mask for this module
 
Void Cache_Module_setMask(Bits16 mask);
// Set the diagnostics mask for this module
 
Configuration settings sourced in ti/sysbios/family/arm/a8/Cache.xdc
var Cache = xdc.useModule('ti.sysbios.family.arm.a8.Cache');
module-wide constants & types
    const Cache.sizeL1dCacheLine// Size of L1 data cache Line = 64;
    const Cache.sizeL1pCacheLine// Size of L1 program cache Line = 64;
    const Cache.sizeL2CacheLine// Size of L2 cache Line = 64;
 
    values of type Cache.Type// Lists of bitmask cache types
        const Cache.Type_L1P// Level 1 Program cache;
        const Cache.Type_L1D// Level 1 Data cache;
        const Cache.Type_L1// Level 1 caches;
        const Cache.Type_L2P// Level 2 Program cache;
        const Cache.Type_L2D// Level 2 Data cache;
        const Cache.Type_L2// Level 2 caches;
        const Cache.Type_ALLP// All Program caches;
        const Cache.Type_ALLD// All Data caches;
        const Cache.Type_ALL// All caches;
module-wide config parameters
    Cache.A_badBlockLength// Asserted in Cache_lock = Assert.Desc {
        msg: "A_badBlockLength: Block length too large. Must be <= L2 way size."
    };
    Cache.A_blockCrossesPage// Asserted in Cache_lock = Assert.Desc {
        msg: "A_blockCrossesPage: Memory block crosses L2 way page boundary."
    };
    Cache.branchPredictionEnabled// Enable Branch Prediction at startup, default is true = Bool true;
    Cache.enableCache// Enable L1 and L2 data and program caches = Bool true;
    Cache.unlockL2Cache// Unlock all 8 L2 cache ways at startup, default is true = Bool true;
 
    Cache.common$// Common module configuration parameters = Types.Common$ undefined;
 
 
const Cache.sizeL1dCacheLine
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Size of L1 data cache Line

Configuration settings
const Cache.sizeL1dCacheLine = 64;
 
C SYNOPSIS
Cache_sizeL1dCacheLine
 
const Cache.sizeL1pCacheLine
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Size of L1 program cache Line

Configuration settings
const Cache.sizeL1pCacheLine = 64;
 
C SYNOPSIS
Cache_sizeL1pCacheLine
 
const Cache.sizeL2CacheLine
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Size of L2 cache Line

Configuration settings
const Cache.sizeL2CacheLine = 64;
 
C SYNOPSIS
Cache_sizeL2CacheLine
 
enum Cache.Type
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Lists of bitmask cache types

Configuration settings
values of type Cache.Type
    const Cache.Type_L1P;
    // Level 1 Program cache
    const Cache.Type_L1D;
    // Level 1 Data cache
    const Cache.Type_L1;
    // Level 1 caches
    const Cache.Type_L2P;
    // Level 2 Program cache
    const Cache.Type_L2D;
    // Level 2 Data cache
    const Cache.Type_L2;
    // Level 2 caches
    const Cache.Type_ALLP;
    // All Program caches
    const Cache.Type_ALLD;
    // All Data caches
    const Cache.Type_ALL;
    // All caches
 
C SYNOPSIS
Cache_Type
 
config Cache.A_badBlockLength  // module-wide
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Asserted in Cache_lock

Configuration settings
Cache.A_badBlockLength = Assert.Desc {
    msg: "A_badBlockLength: Block length too large. Must be <= L2 way size."
};
 
C SYNOPSIS
Cache_A_badBlockLength
 
config Cache.A_blockCrossesPage  // module-wide
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Asserted in Cache_lock

Configuration settings
Cache.A_blockCrossesPage = Assert.Desc {
    msg: "A_blockCrossesPage: Memory block crosses L2 way page boundary."
};
 
C SYNOPSIS
Cache_A_blockCrossesPage
 
config Cache.branchPredictionEnabled  // module-wide
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Enable Branch Prediction at startup, default is true

Configuration settings
Cache.branchPredictionEnabled = Bool true;
 
DETAILS
This flag controls whether Branch Prediction should be automatically enabled or disabled during system startup.
NOTE
Upon reset, the A8's Program Flow Prediction (Branch Prediction) feature is disabled.
C SYNOPSIS
Cache_branchPredictionEnabled
 
config Cache.enableCache  // module-wide
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Enable L1 and L2 data and program caches

Configuration settings
Cache.enableCache = Bool true;
 
DETAILS
To enable a subset of the caches, set this parameter to 'false' and call Cache_enable() within main, passing it only the Cache_Type(s) to be enabled.
Data caching requires the MMU and the memory section/page descriptor cacheable attribute to be enabled.
C SYNOPSIS
Cache_enableCache
 
config Cache.unlockL2Cache  // module-wide
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Unlock all 8 L2 cache ways at startup, default is true

Configuration settings
Cache.unlockL2Cache = Bool true;
 
DETAILS
Ordinarily, the L2 cache ways should all be unlocked at system startup.
During development using CCS, if the application exits while L2 cache ways are locked, the soft-reset function DOES NOT unlock the L2 cache ways. To overcome this problem, the L2 cache ways are unlocked during Cache module startup.
If for any reason this behavior is undesirable, setting this config parameter to false will disable the automatic unlocking of the L2 cache ways.
C SYNOPSIS
Cache_unlockL2Cache
 
metaonly config Cache.common$  // module-wide
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Common module configuration parameters

Configuration settings
Cache.common$ = Types.Common$ undefined;
 
DETAILS
All modules have this configuration parameter. Its name contains the '$' character to ensure it does not conflict with configuration parameters declared by the module. This allows new configuration parameters to be added in the future without any chance of breaking existing modules.
generated on Fri, 10 Jun 2016 23:29:09 GMT