Beginning of high priority nested interrupt support for the ARMv7-M family

This commit is contained in:
Gregory Nutt
2013-12-21 11:03:38 -06:00
parent f8d608a054
commit 3855ce04e8
15 changed files with 390 additions and 55 deletions
+48 -2
View File
@@ -568,8 +568,54 @@
#define NVIC_SYSH_PRIORITY_MAX LPC43M4_SYSH_PRIORITY_MAX
#define NVIC_SYSH_PRIORITY_STEP LPC43M4_SYSH_PRIORITY_INCR
#define NVIC_SYSH_DISABLE_PRIORITY (NVIC_SYSH_PRIORITY_MAX + NVIC_SYSH_PRIORITY_STEP)
#define NVIC_SYSH_SVCALL_PRIORITY NVIC_SYSH_PRIORITY_MAX
/* If CONFIG_ARMV7M_USEBASEPRI is selected, then interrupts will be disabled
* by setting the BASEPRI register to NVIC_SYSH_DISABLE_PRIORITY so that most
* interrupts will not have execution priority. SVCall must have execution
* priority in all cases.
*
* In the normal cases, interrupts are not nest-able and all interrupts run
* at an execution priority between NVIC_SYSH_PRIORITY_MIN and
* NVIC_SYSH_PRIORITY_MAX (with NVIC_SYSH_PRIORITY_MAX reserved for SVCall).
*
* If, in addition, CONFIG_ARCH_HIPRI_INTERRUPT is defined, then special
* high priority interrupts are supported. These are not "nested" in the
* normal sense of the word. These high priority interrupts can interrupt
* normal processing but execute outside of OS (although they can "get back
* into the game" via a PendSV interrupt).
*
* In the normal course of things, interrupts must occasionally be disabled
* using the irqsave() inline function to prevent contention in use of
* resources that may be shared between interrupt level and non-interrupt
* level logic. Now the question arises, if CONFIG_ARCH_HIPRI_INTERRUPT,
* do we disable all interrupts (except SVCall), or do we only disable the
* "normal" interrupts. Since the high priority interrupts cannot interact
* with the OS, you may want to permit the high priority interrupts even if
* interrupts are disabled. The setting CONFIG_ARCH_INT_DISABLEALL can be
* used to select either behavior:
*
* ----------------------------+--------------+----------------------------
* CONFIG_ARCH_HIPRI_INTERRUPT | NO | YES
* ----------------------------+--------------+--------------+-------------
* CONFIG_ARCH_INT_DISABLEALL | N/A | YES | NO
* ----------------------------+--------------+--------------+-------------
* | | | SVCall
* | SVCall | SVCall | HIGH
* Disable here and below --------> MAXNORMAL ---> HIGH --------> MAXNORMAL
* | | MAXNORMAL |
* ----------------------------+--------------+--------------+-------------
*/
#if defined(CONFIG_ARCH_HIPRI_INTERRUPT) && defined(CONFIG_ARCH_INT_DISABLEALL)
# define NVIC_SYSH_MAXNORMAL_PRIORITY (NVIC_SYSH_PRIORITY_MAX + 2*NVIC_SYSH_PRIORITY_STEP)
# define NVIC_SYSH_HIGH_PRIORITY (NVIC_SYSH_PRIORITY_MAX + NVIC_SYSH_PRIORITY_STEP)
# define NVIC_SYSH_DISABLE_PRIORITY NVIC_SYSH_HIGH_PRIORITY
# define NVIC_SYSH_SVCALL_PRIORITY NVIC_SYSH_PRIORITY_MAX
#else
# define NVIC_SYSH_MAXNORMAL_PRIORITY (NVIC_SYSH_PRIORITY_MAX + NVIC_SYSH_PRIORITY_STEP)
# define NVIC_SYSH_HIGH_PRIORITY NVIC_SYSH_PRIORITY_MAX
# define NVIC_SYSH_DISABLE_PRIORITY NVIC_SYSH_MAXNORMAL_PRIORITY
# define NVIC_SYSH_SVCALL_PRIORITY NVIC_SYSH_PRIORITY_MAX
#endif
/************************************************************************************
* Public Types