ARC: [plat-eznps] Use dedicated identity auxiliary register.

With generic "identity" num of CPUs is limited to 256 (8 bit).
We use our alternative AUX register GLOBAL_ID (12 bit).
Now we can support up to 4096 CPUs.

Signed-off-by: Noam Camus <noamc@ezchip.com>
This commit is contained in:
Noam Camus 2013-06-03 15:17:25 +03:00 committed by Vineet Gupta
parent b1f2f6f3cf
commit 86c25466f7
3 changed files with 28 additions and 0 deletions

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@ -36,6 +36,10 @@
#include <asm/irqflags-compact.h>
#include <asm/thread_info.h> /* For THREAD_SIZE */
#ifdef CONFIG_ARC_PLAT_EZNPS
#include <plat/ctop.h>
#endif
/*--------------------------------------------------------------
* Switch to Kernel Mode stack if SP points to User Mode stack
*
@ -296,11 +300,13 @@
bic \reg, sp, (THREAD_SIZE - 1)
.endm
#ifndef CONFIG_ARC_PLAT_EZNPS
/* Get CPU-ID of this core */
.macro GET_CPU_ID reg
lr \reg, [identity]
lsr \reg, \reg, 8
bmsk \reg, \reg, 7
.endm
#endif
#endif /* __ASM_ARC_ENTRY_COMPACT_H */

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@ -16,6 +16,9 @@
#include <asm/asm-offsets.h>
#include <linux/sched.h>
#ifdef CONFIG_ARC_PLAT_EZNPS
#include <plat/ctop.h>
#endif
#define KSP_WORD_OFF ((TASK_THREAD + THREAD_KSP) / 4)
@ -66,10 +69,17 @@ __switch_to(struct task_struct *prev_task, struct task_struct *next_task)
*/
#ifndef CONFIG_SMP
"st %2, [@_current_task] \n\t"
#else
#ifdef CONFIG_ARC_PLAT_EZNPS
"lr r24, [%4] \n\t"
#ifndef CONFIG_EZNPS_MTM_EXT
"lsr r24, r24, 4 \n\t"
#endif
#else
"lr r24, [identity] \n\t"
"lsr r24, r24, 8 \n\t"
"bmsk r24, r24, 7 \n\t"
#endif
"add2 r24, @_current_task, r24 \n\t"
"st %2, [r24] \n\t"
#endif
@ -107,6 +117,9 @@ __switch_to(struct task_struct *prev_task, struct task_struct *next_task)
: "=r"(tmp)
: "n"(KSP_WORD_OFF), "r"(next), "r"(prev)
#ifdef CONFIG_ARC_PLAT_EZNPS
, "i"(CTOP_AUX_LOGIC_GLOBAL_ID)
#endif
: "blink"
);

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@ -195,6 +195,15 @@ struct nps_host_reg_aux_lpc {
#define REG_GIM_P_INT_DST_25 nps_host_reg_non_cl(NPS_GIM_BLKID, 0x149)
#define REG_GIM_P_INT_DST_26 nps_host_reg_non_cl(NPS_GIM_BLKID, 0x14A)
#else
.macro GET_CPU_ID reg
lr \reg, [CTOP_AUX_LOGIC_GLOBAL_ID]
#ifndef CONFIG_EZNPS_MTM_EXT
lsr \reg, \reg, 4
#endif
.endm
#endif /* __ASSEMBLY__ */
#endif /* _PLAT_EZNPS_CTOP_H */