PowerPC Exceptions

Modules
	PowerPC Exception Frame

Files
file	vectors.h
	PowerPC Exceptions API.
file	ppc_exc_address.c
	PowerPC Exceptions implementation.
file	ppc_exc_categories.c
	PowerPC Exceptions implementation.
file	ppc_exc_global_handler.c
	PowerPC Exceptions implementation.
file	ppc_exc_initialize.c
	PowerPC Exceptions implementation.
file	ppc_exc_print.c
	PowerPC Exceptions implementation.
file	ppc_exc_prologue.c
	PowerPC Exceptions implementation.

Macros
#define	ASM_RESET_VECTOR   0x01
#define	ASM_MACH_VECTOR   0x02
#define	ASM_PROT_VECTOR   0x03
#define	ASM_ISI_VECTOR   0x04
#define	ASM_EXT_VECTOR   0x05
#define	ASM_ALIGN_VECTOR   0x06
#define	ASM_PROG_VECTOR   0x07
#define	ASM_FLOAT_VECTOR   0x08
#define	ASM_DEC_VECTOR   0x09
#define	ASM_SYS_VECTOR   0x0C
#define	ASM_TRACE_VECTOR   0x0D
#define	ASM_PPC405_APU_UNAVAIL_VECTOR   ASM_60X_VEC_ASSIST_VECTOR
#define	ASM_8XX_FLOATASSIST_VECTOR   0x0E
#define	ASM_8XX_SOFTEMUL_VECTOR   0x10
#define	ASM_8XX_ITLBMISS_VECTOR   0x11
#define	ASM_8XX_DTLBMISS_VECTOR   0x12
#define	ASM_8XX_ITLBERROR_VECTOR   0x13
#define	ASM_8XX_DTLBERROR_VECTOR   0x14
#define	ASM_8XX_DBREAK_VECTOR   0x1C
#define	ASM_8XX_IBREAK_VECTOR   0x1D
#define	ASM_8XX_PERIFBREAK_VECTOR   0x1E
#define	ASM_8XX_DEVPORT_VECTOR   0x1F
#define	ASM_5XX_FLOATASSIST_VECTOR   0x0E
#define	ASM_5XX_SOFTEMUL_VECTOR   0x10
#define	ASM_5XX_IPROT_VECTOR   0x13
#define	ASM_5XX_DPROT_VECTOR   0x14
#define	ASM_5XX_DBREAK_VECTOR   0x1C
#define	ASM_5XX_IBREAK_VECTOR   0x1D
#define	ASM_5XX_MEBREAK_VECTOR   0x1E
#define	ASM_5XX_NMEBREAK_VECTOR   0x1F
#define	ASM_60X_VEC_VECTOR   0x0A
#define	ASM_60X_PERFMON_VECTOR   0x0F
#define	ASM_60X_IMISS_VECTOR   0x10
#define	ASM_60X_DLMISS_VECTOR   0x11
#define	ASM_60X_DSMISS_VECTOR   0x12
#define	ASM_60X_ADDR_VECTOR   0x13
#define	ASM_60X_SYSMGMT_VECTOR   0x14
#define	ASM_60X_VEC_ASSIST_VECTOR   0x16
#define	ASM_60X_ITM_VECTOR   0x17
#define	ASM_BOOKE_CRIT_VECTOR   0x01
#define	ASM_BOOKE_DEC_VECTOR   0x10
#define	ASM_BOOKE_ITLBMISS_VECTOR   0x11
#define	ASM_BOOKE_DTLBMISS_VECTOR   0x12
#define	ASM_BOOKE_FIT_VECTOR   0x13
#define	ASM_BOOKE_WDOG_VECTOR   0x14
#define	ASM_BOOKE_APU_VECTOR   0x18
#define	ASM_BOOKE_DEBUG_VECTOR   ASM_TRACE_VECTOR
#define	ASM_E500_SPE_UNAVAILABLE_VECTOR   ASM_60X_VEC_VECTOR
#define	ASM_E500_EMB_FP_DATA_VECTOR   0x19
#define	ASM_E500_EMB_FP_ROUND_VECTOR   0x1A
#define	ASM_E500_PERFMON_VECTOR   ASM_60X_PERFMON_VECTOR
#define	ASM_E300_CRIT_VECTOR   0x0A
#define	ASM_E300_PERFMON_VECTOR   ASM_60X_PERFMON_VECTOR
#define	ASM_E300_IMISS_VECTOR   ASM_60X_IMISS_VECTOR /* Special case: Shadowed GPRs */
#define	ASM_E300_DLMISS_VECTOR   ASM_60X_DLMISS_VECTOR /* Special case: Shadowed GPRs */
#define	ASM_E300_DSMISS_VECTOR   ASM_60X_DSMISS_VECTOR /* Special case: Shadowed GPRs */
#define	ASM_E300_ADDR_VECTOR   ASM_60X_ADDR_VECTOR
#define	ASM_E300_SYSMGMT_VECTOR   ASM_60X_SYSMGMT_VECTOR
#define	LAST_VALID_EXC   0x1F
#define	ASM_60X_VEC_VECTOR_OFFSET   0xf20
#define	ASM_PPC405_FIT_VECTOR_OFFSET   0x1010
#define	ASM_PPC405_WDOG_VECTOR_OFFSET   0x1020
#define	ASM_PPC405_TRACE_VECTOR_OFFSET   0x2000

Typedefs
typedef void(*	exception_handler_t) (BSP_Exception_frame *)
	Global exception handler type.
typedef uint8_t	ppc_exc_categories[LAST_VALID_EXC+1]
	Categorie set type.
typedef int(*	ppc_exc_handler_t) (BSP_Exception_frame *f, unsigned vector)
	High-level exception handler type.

Enumerations
enum	ppc_exc_category {   PPC_EXC_INVALID = 0 , PPC_EXC_ASYNC = 1 , PPC_EXC_CLASSIC = 2 , PPC_EXC_CLASSIC_ASYNC = PPC_EXC_CLASSIC | PPC_EXC_ASYNC ,   PPC_EXC_405_CRITICAL = 4 , PPC_EXC_405_CRITICAL_ASYNC = PPC_EXC_405_CRITICAL | PPC_EXC_ASYNC , PPC_EXC_BOOKE_CRITICAL = 6 , PPC_EXC_BOOKE_CRITICAL_ASYNC = PPC_EXC_BOOKE_CRITICAL | PPC_EXC_ASYNC ,   PPC_EXC_E500_MACHCHK = 8 , PPC_EXC_E500_MACHCHK_ASYNC = PPC_EXC_E500_MACHCHK | PPC_EXC_ASYNC , PPC_EXC_NAKED = 10 }
	Exception categories. More...

Functions
void	C_exception_handler (BSP_Exception_frame *excPtr)
	Default global exception handler.
void	BSP_printStackTrace (const BSP_Exception_frame *excPtr)
void *	ppc_exc_vector_address (unsigned vector, void *vector_base)
	Returns the entry address of the vector.
const ppc_exc_categories *	ppc_exc_categories_for_cpu (ppc_cpu_id_t cpu)
	Returns the category set for a CPU of type cpu, or NULL if there is no category set available for this CPU.
ppc_exc_category	ppc_exc_category_for_vector (const ppc_exc_categories *categories, unsigned vector)
	Returns the category for the vector vector using the category set categories.
rtems_status_code	ppc_exc_make_prologue (unsigned vector, void *vector_base, ppc_exc_category category, uint32_t *prologue, size_t *prologue_size)
	Makes a minimal prologue for the vector vector with the category category.
void	ppc_exc_initialize_with_vector_base (uintptr_t interrupt_stack_begin, void *vector_base)
	Initializes the exception handling.
int	ppc_exc_handler_default (BSP_Exception_frame *f, unsigned int vector)
	Default high-level exception handler.
rtems_status_code	ppc_exc_set_handler (unsigned vector, ppc_exc_handler_t hdl)
	Set high-level exception handler.
ppc_exc_handler_t	ppc_exc_get_handler (unsigned vector)
	Returns the currently active high-level exception handler.
void	ppc_exc_wrapup (BSP_Exception_frame *f)
int	ppc_exc_alignment_handler (BSP_Exception_frame *frame, unsigned excNum)
	Standard aligment handler.

Variables
uint32_t	ppc_exc_msr_bits
	Bits for MSR update.
uint32_t	ppc_exc_cache_wb_check
	Cache write back check flag.
ppc_exc_handler_t	ppc_exc_handler_table [LAST_VALID_EXC+1]
	High-level exception handler table.
exception_handler_t	globalExceptHdl
	Global exception handler.
uint32_t(*	ppc_exc_get_DAR )(void)
	Function for DAR access.

Detailed Description

Typedef Documentation

ppc_exc_handler_t

typedef int(* ppc_exc_handler_t) (BSP_Exception_frame *f, unsigned vector)

High-level exception handler type.

Return values

0	The exception was handled and normal execution may resume.
-1	Reject the exception resulting in a call of the global exception handler.
other	Reserved, do not use.

Enumeration Type Documentation

ppc_exc_category

enum ppc_exc_category

Exception categories.

Exceptions of different categories use different SRR registers to save the machine state and do different things in the prologue and epilogue.

For now, the CPU descriptions assume this fits into 8 bits.

Function Documentation

ppc_exc_alignment_handler()

int ppc_exc_alignment_handler	(	BSP_Exception_frame *	frame,
		unsigned	excNum
	)

Standard aligment handler.

Return values

0	Performed a dcbz instruction.
-1	Otherwise.

ppc_exc_handler_default()

int ppc_exc_handler_default	(	BSP_Exception_frame *	f,
		unsigned int	vector
	)

Default high-level exception handler.

Return values

-1

Always.

ppc_exc_initialize_with_vector_base()

void ppc_exc_initialize_with_vector_base	(	uintptr_t	interrupt_stack_begin,
		void *	vector_base
	)

Initializes the exception handling.

See also

ppc_exc_initialize().

ppc_exc_make_prologue()

rtems_status_code ppc_exc_make_prologue	(	unsigned	vector,
		void *	vector_base,
		ppc_exc_category	category,
		uint32_t *	prologue,
		size_t *	prologue_size
	)

Makes a minimal prologue for the vector vector with the category category.

The minimal prologue will be copied to prologue. Not more than prologue_size bytes will be copied. Returns the actual minimal prologue size in bytes in prologue_size.

Return values

RTEMS_SUCCESSFUL	Minimal prologue successfully made.
RTEMS_INVALID_ID	Invalid vector number.
RTEMS_INVALID_NUMBER	Invalid category.
RTEMS_INVALID_SIZE	Prologue size to small.

ppc_exc_set_handler()

rtems_status_code ppc_exc_set_handler	(	unsigned	vector,
		ppc_exc_handler_t	hdl
	)

Set high-level exception handler.

Hook C exception handlers.

• handlers for asynchronous exceptions run on the ISR stack with thread-dispatching disabled.
• handlers for synchronous exceptions run on the task stack with thread-dispatching enabled.

If a particular slot is NULL then the traditional 'globalExcHdl' is used.

ppc_exc_set_handler() registers a handler (returning 0 on success, -1 if the vector argument is too big).

It is legal to set a NULL handler. This leads to the globalExcHdl being called if an exception for 'vector' occurs.

Return values

RTEMS_SUCCESSFUL	Successful operation.
RTEMS_INVALID_ID	Invalid vector number.
RTEMS_RESOURCE_IN_USE	Handler table is read-only and handler does not match.

ppc_exc_vector_address()

void * ppc_exc_vector_address	(	unsigned	vector,
		void *	vector_base
	)

Returns the entry address of the vector.

Parameters

[in]	vector	The vector number.
[in]	vector_base	The vector table base address.

Variable Documentation

ppc_exc_cache_wb_check

uint32_t ppc_exc_cache_wb_check

extern

Cache write back check flag.

(See README under CAVEATS). During initialization a check is performed to assert that write-back caching is enabled for memory accesses. If a BSP runs entirely without any caching then it should set this variable to zero prior to initializing exceptions in order to skip the test. NOTE: The code does NOT support mapping memory with cache-attributes other than write-back (unless the entire cache is physically disabled)

ppc_exc_get_DAR

uint32_t(* ppc_exc_get_DAR) (void) ( void  )

extern

Function for DAR access.

CPU support may store the address of a function here that can be used by the default exception handler to obtain fault-address info which is helpful. Unfortunately, the SPR holding this information is not uniform across PPC families so we need assistance from CPU support

ppc_exc_msr_bits

uint32_t ppc_exc_msr_bits

extern

Bits for MSR update.

Bits in MSR that are enabled during execution of exception handlers / ISRs (on classic PPC these are DR/IR/RI [default], on bookE-style CPUs they should be set to 0 during initialization)

By default, the setting of these bits that is in effect when exception handling is initialized is used.