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authorAdrian Bunk <bunk@kernel.org>2008-07-24 00:28:50 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2008-07-24 13:47:24 -0400
commitf606ddf42fd4edc558eeb48bfee66d2c591571d2 (patch)
tree193f00db121201255b2629fce43b99a53c4ec735 /arch/v850/kernel/highres_timer.c
parent99764fa4ceeecba8b9e0a8a5565b418a2e94f83b (diff)
remove the v850 port
Trying to compile the v850 port brings many compile errors, one of them exists since at least kernel 2.6.19. There also seems to be noone willing to bring this port back into a usable state. This patch therefore removes the v850 port. If anyone ever decides to revive the v850 port the code will still be available from older kernels, and it wouldn't be impossible for the port to reenter the kernel if it would become actively maintained again. Signed-off-by: Adrian Bunk <bunk@kernel.org> Acked-by: Greg Ungerer <gerg@uclinux.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/v850/kernel/highres_timer.c')
-rw-r--r--arch/v850/kernel/highres_timer.c132
1 files changed, 0 insertions, 132 deletions
diff --git a/arch/v850/kernel/highres_timer.c b/arch/v850/kernel/highres_timer.c
deleted file mode 100644
index b16ad1eaf966..000000000000
--- a/arch/v850/kernel/highres_timer.c
+++ /dev/null
@@ -1,132 +0,0 @@
1/*
2 * arch/v850/kernel/highres_timer.c -- High resolution timing routines
3 *
4 * Copyright (C) 2001,02,03 NEC Electronics Corporation
5 * Copyright (C) 2001,02,03 Miles Bader <miles@gnu.org>
6 *
7 * This file is subject to the terms and conditions of the GNU General
8 * Public License. See the file COPYING in the main directory of this
9 * archive for more details.
10 *
11 * Written by Miles Bader <miles@gnu.org>
12 */
13
14#include <asm/system.h>
15#include <asm/v850e_timer_d.h>
16#include <asm/highres_timer.h>
17
18#define HIGHRES_TIMER_USEC_SHIFT 12
19
20/* Pre-calculated constant used for converting ticks to real time
21 units. We initialize it to prevent it being put into BSS. */
22static u32 highres_timer_usec_prescale = 1;
23
24void highres_timer_slow_tick_irq (void) __attribute__ ((noreturn));
25void highres_timer_slow_tick_irq (void)
26{
27 /* This is an interrupt handler, so it must be very careful to
28 not to trash any registers. At this point, the stack-pointer
29 (r3) has been saved in the chip ram location ENTRY_SP by the
30 interrupt vector, so we can use it as a scratch register; we
31 must also restore it before returning. */
32 asm ("ld.w %0[r0], sp;"
33 "add 1, sp;"
34 "st.w sp, %0[r0];"
35 "ld.w %1[r0], sp;" /* restore pre-irq stack-pointer */
36 "reti"
37 ::
38 "i" (HIGHRES_TIMER_SLOW_TICKS_ADDR),
39 "i" (ENTRY_SP_ADDR)
40 : "memory");
41}
42
43void highres_timer_reset (void)
44{
45 V850E_TIMER_D_TMD (HIGHRES_TIMER_TIMER_D_UNIT) = 0;
46 HIGHRES_TIMER_SLOW_TICKS = 0;
47}
48
49void highres_timer_start (void)
50{
51 u32 fast_tick_rate;
52
53 /* Start hardware timer. */
54 v850e_timer_d_configure (HIGHRES_TIMER_TIMER_D_UNIT,
55 HIGHRES_TIMER_SLOW_TICK_RATE);
56
57 fast_tick_rate =
58 (V850E_TIMER_D_BASE_FREQ
59 >> V850E_TIMER_D_DIVLOG2 (HIGHRES_TIMER_TIMER_D_UNIT));
60
61 /* The obvious way of calculating microseconds from fast ticks
62 is to do:
63
64 usec = fast_ticks * 10^6 / fast_tick_rate
65
66 However, divisions are much slower than multiplications, and
67 the above calculation can overflow, so we do this instead:
68
69 usec = fast_ticks * (10^6 * 2^12 / fast_tick_rate) / 2^12
70
71 since we can pre-calculate (10^6 * (2^12 / fast_tick_rate))
72 and use a shift for dividing by 2^12, this avoids division,
73 and is almost as accurate (it differs by about 2 microseconds
74 at the extreme value of the fast-tick counter's ranger). */
75 highres_timer_usec_prescale = ((1000000 << HIGHRES_TIMER_USEC_SHIFT)
76 / fast_tick_rate);
77
78 /* Enable the interrupt (which is hardwired to this use), and
79 give it the highest priority. */
80 V850E_INTC_IC (IRQ_INTCMD (HIGHRES_TIMER_TIMER_D_UNIT)) = 0;
81}
82
83void highres_timer_stop (void)
84{
85 /* Stop the timer. */
86 V850E_TIMER_D_TMCD (HIGHRES_TIMER_TIMER_D_UNIT) =
87 V850E_TIMER_D_TMCD_CAE;
88 /* Disable its interrupt, just in case. */
89 v850e_intc_disable_irq (IRQ_INTCMD (HIGHRES_TIMER_TIMER_D_UNIT));
90}
91
92inline void highres_timer_read_ticks (u32 *slow_ticks, u32 *fast_ticks)
93{
94 int flags;
95 u32 fast_ticks_1, fast_ticks_2, _slow_ticks;
96
97 local_irq_save (flags);
98 fast_ticks_1 = V850E_TIMER_D_TMD (HIGHRES_TIMER_TIMER_D_UNIT);
99 _slow_ticks = HIGHRES_TIMER_SLOW_TICKS;
100 fast_ticks_2 = V850E_TIMER_D_TMD (HIGHRES_TIMER_TIMER_D_UNIT);
101 local_irq_restore (flags);
102
103 if (fast_ticks_2 < fast_ticks_1)
104 _slow_ticks++;
105
106 *slow_ticks = _slow_ticks;
107 *fast_ticks = fast_ticks_2;
108}
109
110inline void highres_timer_ticks_to_timeval (u32 slow_ticks, u32 fast_ticks,
111 struct timeval *tv)
112{
113 unsigned long sec, sec_rem, usec;
114
115 usec = ((fast_ticks * highres_timer_usec_prescale)
116 >> HIGHRES_TIMER_USEC_SHIFT);
117
118 sec = slow_ticks / HIGHRES_TIMER_SLOW_TICK_RATE;
119 sec_rem = slow_ticks % HIGHRES_TIMER_SLOW_TICK_RATE;
120
121 usec += sec_rem * (1000000 / HIGHRES_TIMER_SLOW_TICK_RATE);
122
123 tv->tv_sec = sec;
124 tv->tv_usec = usec;
125}
126
127void highres_timer_read (struct timeval *tv)
128{
129 u32 fast_ticks, slow_ticks;
130 highres_timer_read_ticks (&slow_ticks, &fast_ticks);
131 highres_timer_ticks_to_timeval (slow_ticks, fast_ticks, tv);
132}