diff options
Diffstat (limited to 'pk/ppe42/ppe42_irq.h')
| -rw-r--r-- | pk/ppe42/ppe42_irq.h | 112 |
1 files changed, 0 insertions, 112 deletions
diff --git a/pk/ppe42/ppe42_irq.h b/pk/ppe42/ppe42_irq.h index 6567af64..89948d60 100644 --- a/pk/ppe42/ppe42_irq.h +++ b/pk/ppe42/ppe42_irq.h @@ -139,79 +139,6 @@ UNLESS__PPE42_IRQ_CORE_C__(extern) volatile void* __ppe42_debug_arg; - -// Note: Why PK_IRQ_FAST2FULL (below) is implemented so strangely. -// -// I am adamant that I want to have a a macro in the 'C' environment to create -// these bridge functions. However the limitations of the C preprocessor and -// the intelligence of the GCC 'asm' facility consipre against a -// straightforward solution. The only way that I was able to find to get -// naked assembly code into the output stream is to use 'asm' with simple -// strings - I couldn't make it work with any kind of argument, as 'asm' would -// reinterpret the arguments and resulting assembler code in various ways. -// -// There is another alternative that I tried wherby I created a subroutine -// call and then filled in the subroutine body with 'asm' code. However, the -// subroutine wrapper that GCC creates only works for PowerPC fast-mode -// handlers if GCC is invoked with optimization, which ensures that the -// wrapper doesn't touch the stack pointer or other registers. True, we'll -// always use optimization, but I did not want to have to make this -// requirement for using this macro. - -/// This macro creates a 'bridge' handler that converts the initial fast-mode -/// IRQ dispatch into a call of a full-mode IRQ handler. The full-mode -/// handler is defined by the user (presumably as a \c C subroutine) and has -/// the same prototype (type PkIrqHandler) as the fast handler. -/// -/// \param fast_handler This will be the global function name of the fast -/// IRQ handler created by this macro. This is the symbol -/// that should be passed in as the \a handler argument -/// of \c pk_irq_setup() and \c pk_irq_handler_set(). -/// -/// \param full_handler This is the name of the user-defined full-mode -/// handler which is invoked through this bridge. -/// -/// \e BUG \e ALERT : Beware of passing the \c full_handler to IRQ setup -/// APIs. This won't be caught by the compiler (because the \c full_handler -/// has the correct prototype) and will lead to nasty bugs. Always pass in -/// the \c fast_handler symbol to IRQ setup APIS. -/// -/// The code stream injected into the GCC assembler output in response to -/// -/// PK_IRQ_FAST2FULL(fast_handler, full_handler) -/// -/// is (comments added for clarification) : -/// -/// \code -/// .text -/// .global fast_handler -/// .align 5 # Hard-coded PPE42 cache-line alignment -/// fast_handler = . # Can't macro expand LABEL: - this is equivalent -/// bl __pk_irq_fast2full # The fast-mode to full-mode conversion sequence -/// bl full_handler -/// b __pk_irq_full_mode_exit -/// \endcode -/// -/// The macro also declares the prototype of the fast handler: -/// -/// \code -/// PK_IRQ_HANDLER(fast_handler); -/// \endcode -/// - -#define PK_IRQ_FAST2FULL(fast_handler, full_handler) \ - PK_IRQ_HANDLER(fast_handler); \ - __PK_IRQ_FAST2FULL(.global fast_handler, fast_handler = ., bl full_handler) - -#define __PK_IRQ_FAST2FULL(global, label, call) \ -asm(".text"); \ -asm(#global); \ -asm(".align 5"); \ -asm(#label); \ -asm("bl __pk_irq_fast2full"); \ -asm(#call); \ -asm("b __pk_irq_full_mode_exit"); - #endif /* __ASSEMBLER__ */ // It's hard to be portable and get all of the definitions and headers in the @@ -228,45 +155,6 @@ asm("b __pk_irq_full_mode_exit"); /// \page ppe42_irq_macros_page PPE42 PK IRQ Assembler Macros /// /// -/// \section fast2full_asm Fast-Mode to Full-Mode Handler Conversion -/// -/// This macro produces the calling sequence required to convert a -/// fast-mode interrupt handler to a full-mode interrupt handler. The -/// full-mode handler is implemented by another subroutine. The -/// requirements for invoking this macro are: -/// -/// \li The stack pointer and stack must be exactly as they were when the -/// fast-mode handler was entered. -/// -/// \li No changes have been made to the MSR - the interrupt level must -/// remain disabled. -/// -/// \li The handler owns the fast context and has not modified the other -/// register context. The conversion process will not modify any -/// register in the fast context (other than the LR used for -/// subroutine linkage). -/// -/// The final condition above means that the \a full_handler will -/// begin with the fast-mode context exactly as it was (save for LR) -/// at conversion, including the contents of GPR3-7 (the first 5 -/// PowerPC ABI paramater passing registers) and the entire CR. -/// -/// Forms: -/// -/// \c _pk_irq_fast2full \a full_handler -/// \cond - -#ifdef __ASSEMBLER__ - - .macro _pk_irq_fast2full full_handler - bl __pk_irq_fast2full - bl \full_handler - b __pk_irq_full_mode_exit - .endm - -#endif /* __ASSEMBLER__ */ - -/// \endcond #ifndef __ASSEMBLER__ |
