Ajay Mohan / Rasperf

Commit 38da92fb36dc05cb3a4fc28bc978e1c4d3dbade1

Authored by Ajay Mohan 2016-03-04 23:29:08 -0800

Exists in master

Header File addition and kern Module change

Showing 3 changed files with 82 additions and 56 deletions Side-by-side Diff

drivers/enableCCNT.c
drivers/osproject.c
rasperf.h

	1	+/**
	2	+** Kernel Module to enable Performance
	3	+** Monitoring Register (PMUSEREN) to enable
	4	+** user to read through cycle counter and
	5	+** other registers in the co-processor.
	6	+**/
	7	+#include <linux/module.h>
	8	+
	9	+#define ARMV7_PMNC_E (1 << 0) /* Enable all counters */
	10	+#define ARMV7_PMNC_P (1 << 1) /* Reset all counters */
	11	+#define ARMV7_PMNC_C (1 << 2) /* Cycle counter reset */
	12	+#define ARMV7_PMNC_D (1 << 3) /* CCNT counts every 64th cpu cycle */
	13	+#define ARMV7_PMNC_X (1 << 4) /* Export to ETM */
	14	+#define ARMV7_PMNC_DP (1 << 5) /* Disable CCNT if non-invasive debug*/
	15	+#define ARMV7_PMNC_N_SHIFT 11 /* Number of counters supported */
	16	+#define ARMV7_PMNC_N_MASK 0x1f
	17	+#define ARMV7_PMNC_MASK 0x3f /* Mask for writable bits */
	18	+
	19	+/*101b9173
	20	+static u32 armv7_pmnc_read(void)
	21	+{
	22	+ u32 val;
	23	+ asm volatile("mrc p15, 0, %0, c9, c12, 0" : "=r"(val));
	24	+ return val;
	25	+}
	26	+
	27	+static void armv7_pmnc_write(u32 val)
	28	+{
	29	+ val &= ARMV7_PMNC_MASK;
	30	+ isb();
	31	+ asm volatile("mcr p15, 0, %0, c9, c12, 0" :: "r"(val));
	32	+}
	33	+*/
	34	+
	35	+int init_module()
	36	+{
	37	+ unsigned int regr;
	38	+ unsigned int i;
	39	+ unsigned int a, b;
	40	+
	41	+ // 1. Enable "User Enable Register"
	42	+ asm volatile("mcr p15, 0, %0, c9, c14, 0\n\t" :: "r" (0x00000001));
	43	+
	44	+ // 2. Reset Performance Monitor Control Register(PMCR), Count Enable Set
	45	+ // Register, and Overflow Flag Status Register
	46	+ asm volatile ("mcr p15, 0, %0, c9, c12, 0\n\t" :: "r"(0x00000017));
	47	+ asm volatile ("mcr p15, 0, %0, c9, c12, 1\n\t" :: "r"(0x8000000f));
	48	+ asm volatile ("mcr p15, 0, %0, c9, c12, 3\n\t" :: "r"(0x8000000f));
	49	+
	50	+ // 3. Disable Interrupt Enable Clear Register
	51	+ asm volatile("mcr p15, 0, %0, c9, c14, 2\n\t" :: "r" (~0));
	52	+
	53	+ // read back to confirm
	54	+ asm volatile("mrc p15, 0, %0, c9, c14, 0" : "=r" (regr));
	55	+ pr_info("regr: %x\n", regr);
	56	+ regr = 0;
	57	+ for (i = 0; i < 1000; i++) {
	58	+ asm volatile("mrc p15, 0, %0, c9, c13, 0" : "=r" (a));
	59	+ asm volatile("mrc p15, 0, %0, c9, c13, 0" : "=r" (b));
	60	+ regr += b - a;
	61	+ pr_info("overhead: %u\n", b - a);
	62	+ }
	63	+ pr_info("Measurement overhead: %u\n", regr);
	64	+ return 1;
	65	+}
	66	+
	67	+void cleanup_module()
	68	+{
	69	+}

1		-/*
2		- * * hello.c The simplest kernel module.
3		- * */
4		-#include <linux/module.h>
5		-
6		-#define ARMV7_PMNC_E (1 << 0) /* Enable all counters */
7		-#define ARMV7_PMNC_P (1 << 1) /* Reset all counters */
8		-#define ARMV7_PMNC_C (1 << 2) /* Cycle counter reset */
9		-#define ARMV7_PMNC_D (1 << 3) /* CCNT counts every 64th cpu cycle */
10		-#define ARMV7_PMNC_X (1 << 4) /* Export to ETM */
11		-#define ARMV7_PMNC_DP (1 << 5) /* Disable CCNT if non-invasive debug*/
12		-#define ARMV7_PMNC_N_SHIFT 11 /* Number of counters supported */
13		-#define ARMV7_PMNC_N_MASK 0x1f
14		-#define ARMV7_PMNC_MASK 0x3f /* Mask for writable bits */
15		-
16		-/*101b9173
17		-static u32 armv7_pmnc_read(void)
18		-{
19		- u32 val;
20		- asm volatile("mrc p15, 0, %0, c9, c12, 0" : "=r"(val));
21		- return val;
22		-}
23		-
24		-static void armv7_pmnc_write(u32 val)
25		-{
26		- val &= ARMV7_PMNC_MASK;
27		- isb();
28		- asm volatile("mcr p15, 0, %0, c9, c12, 0" :: "r"(val));
29		-}
30		-*/
31		-
32		-int init_module()
33		-{
34		- unsigned int regr;
35		- unsigned int i;
36		- unsigned int a, b;
37		-
38		- asm volatile("mrc p15, 0, %0, c9, c14, 0" : "=r" (regr));
39		- pr_info("regr: %x\n", regr);
40		-
41		- regr = 0;
42		- for (i = 0; i < 1000; i++) {
43		- asm volatile("mrc p15, 0, %0, c9, c13, 0" : "=r" (a));
44		- asm volatile("mrc p15, 0, %0, c9, c13, 0" : "=r" (b));
45		- regr += b - a;
46		- pr_info("overhead: %u\n", b - a);
47		- }
48		- pr_info("Measurement overhead: %u\n", regr);
49		-
50		-
51		- return 1;
52		-}
53		-
54		-void cleanup_module()
55		-{
56		-}

	1	+#ifndef __RASPERF_H__
	2	+#define __RASPERF_H__
	3	+
	4	+#define getTime(var) \
	5	+ asm volatile (\
	6	+ "mrc p15, 0, %0, c9, c13, 0":\
	7	+ "=r" (var));\
	8	+#define readCCNTStatus(var) \
	9	+ asm volatile (\
	10	+ "mrc p15, 0, %0, c9, c14, 0":\
	11	+ "=r" (var));\