aboutsummaryrefslogtreecommitdiff
path: root/arch/powerpc/platforms/8xx/m8xx_setup.c
blob: 242954c4293f64fcc6222a15de3eb6df6e8c0941 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
/*
 *  Copyright (C) 1995  Linus Torvalds
 *  Adapted from 'alpha' version by Gary Thomas
 *  Modified by Cort Dougan (cort@cs.nmt.edu)
 *  Modified for MBX using prep/chrp/pmac functions by Dan (dmalek@jlc.net)
 *  Further modified for generic 8xx by Dan.
 */

/*
 * bootup setup stuff..
 */

#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/time.h>
#include <linux/rtc.h>
#include <linux/fsl_devices.h>

#include <asm/io.h>
#include <asm/mpc8xx.h>
#include <asm/8xx_immap.h>
#include <asm/prom.h>
#include <asm/fs_pd.h>
#include <mm/mmu_decl.h>

#include <sysdev/mpc8xx_pic.h>

#include "mpc8xx.h"

struct mpc8xx_pcmcia_ops m8xx_pcmcia_ops;

extern int cpm_pic_init(void);
extern int cpm_get_irq(void);

/* A place holder for time base interrupts, if they are ever enabled. */
static irqreturn_t timebase_interrupt(int irq, void *dev)
{
	printk ("timebase_interrupt()\n");

	return IRQ_HANDLED;
}

static struct irqaction tbint_irqaction = {
	.handler = timebase_interrupt,
	.name = "tbint",
};

/* per-board overridable init_internal_rtc() function. */
void __init __attribute__ ((weak))
init_internal_rtc(void)
{
	sit8xx_t __iomem *sys_tmr = immr_map(im_sit);

	/* Disable the RTC one second and alarm interrupts. */
	clrbits16(&sys_tmr->sit_rtcsc, (RTCSC_SIE | RTCSC_ALE));

	/* Enable the RTC */
	setbits16(&sys_tmr->sit_rtcsc, (RTCSC_RTF | RTCSC_RTE));
	immr_unmap(sys_tmr);
}

static int __init get_freq(char *name, unsigned long *val)
{
	struct device_node *cpu;
	const unsigned int *fp;
	int found = 0;

	/* The cpu node should have timebase and clock frequency properties */
	cpu = of_find_node_by_type(NULL, "cpu");

	if (cpu) {
		fp = of_get_property(cpu, name, NULL);
		if (fp) {
			found = 1;
			*val = *fp;
		}

		of_node_put(cpu);
	}

	return found;
}

/* The decrementer counts at the system (internal) clock frequency divided by
 * sixteen, or external oscillator divided by four.  We force the processor
 * to use system clock divided by sixteen.
 */
void __init mpc8xx_calibrate_decr(void)
{
	struct device_node *cpu;
	cark8xx_t __iomem *clk_r1;
	car8xx_t __iomem *clk_r2;
	sitk8xx_t __iomem *sys_tmr1;
	sit8xx_t __iomem *sys_tmr2;
	int irq, virq;

	clk_r1 = immr_map(im_clkrstk);

	/* Unlock the SCCR. */
	out_be32(&clk_r1->cark_sccrk, ~KAPWR_KEY);
	out_be32(&clk_r1->cark_sccrk, KAPWR_KEY);
	immr_unmap(clk_r1);

	/* Force all 8xx processors to use divide by 16 processor clock. */
	clk_r2 = immr_map(im_clkrst);
	setbits32(&clk_r2->car_sccr, 0x02000000);
	immr_unmap(clk_r2);

	/* Processor frequency is MHz.
	 */
	ppc_proc_freq = 50000000;
	if (!get_freq("clock-frequency", &ppc_proc_freq))
		printk(KERN_ERR "WARNING: Estimating processor frequency "
		                "(not found)\n");

	ppc_tb_freq = ppc_proc_freq / 16;
	printk("Decrementer Frequency = 0x%lx\n", ppc_tb_freq);

	/* Perform some more timer/timebase initialization.  This used
	 * to be done elsewhere, but other changes caused it to get
	 * called more than once....that is a bad thing.
	 *
	 * First, unlock all of the registers we are going to modify.
	 * To protect them from corruption during power down, registers
	 * that are maintained by keep alive power are "locked".  To
	 * modify these registers we have to write the key value to
	 * the key location associated with the register.
	 * Some boards power up with these unlocked, while others
	 * are locked.  Writing anything (including the unlock code?)
	 * to the unlocked registers will lock them again.  So, here
	 * we guarantee the registers are locked, then we unlock them
	 * for our use.
	 */
	sys_tmr1 = immr_map(im_sitk);
	out_be32(&sys_tmr1->sitk_tbscrk, ~KAPWR_KEY);
	out_be32(&sys_tmr1->sitk_rtcsck, ~KAPWR_KEY);
	out_be32(&sys_tmr1->sitk_tbk, ~KAPWR_KEY);
	out_be32(&sys_tmr1->sitk_tbscrk, KAPWR_KEY);
	out_be32(&sys_tmr1->sitk_rtcsck, KAPWR_KEY);
	out_be32(&sys_tmr1->sitk_tbk, KAPWR_KEY);
	immr_unmap(sys_tmr1);

	init_internal_rtc();

	/* Enabling the decrementer also enables the timebase interrupts
	 * (or from the other point of view, to get decrementer interrupts
	 * we have to enable the timebase).  The decrementer interrupt
	 * is wired into the vector table, nothing to do here for that.
	 */
	cpu = of_find_node_by_type(NULL, "cpu");
	virq= irq_of_parse_and_map(cpu, 0);
	irq = irq_map[virq].hwirq;

	sys_tmr2 = immr_map(im_sit);
	out_be16(&sys_tmr2->sit_tbscr, ((1 << (7 - (irq/2))) << 8) |
					(TBSCR_TBF | TBSCR_TBE));
	immr_unmap(sys_tmr2);

	if (setup_irq(virq, &tbint_irqaction))
		panic("Could not allocate timer IRQ!");
}

/* The RTC on the MPC8xx is an internal register.
 * We want to protect this during power down, so we need to unlock,
 * modify, and re-lock.
 */

int mpc8xx_set_rtc_time(struct rtc_time *tm)
{
	sitk8xx_t __iomem *sys_tmr1;
	sit8xx_t __iomem *sys_tmr2;
	int time;

	sys_tmr1 = immr_map(im_sitk);
	sys_tmr2 = immr_map(im_sit);
	time = mktime(tm->tm_year+1900, tm->tm_mon+1, tm->tm_mday,
	              tm->tm_hour, tm->tm_min, tm->tm_sec);

	out_be32(&sys_tmr1->sitk_rtck, KAPWR_KEY);
	out_be32(&sys_tmr2->sit_rtc, time);
	out_be32(&sys_tmr1->sitk_rtck, ~KAPWR_KEY);

	immr_unmap(sys_tmr2);
	immr_unmap(sys_tmr1);
	return 0;
}

void mpc8xx_get_rtc_time(struct rtc_time *tm)
{
	unsigned long data;
	sit8xx_t __iomem *sys_tmr = immr_map(im_sit);

	/* Get time from the RTC. */
	data = in_be32(&sys_tmr->sit_rtc);
	to_tm(data, tm);
	tm->tm_year -= 1900;
	tm->tm_mon -= 1;
	immr_unmap(sys_tmr);
	return;
}

void mpc8xx_restart(char *cmd)
{
	car8xx_t __iomem *clk_r = immr_map(im_clkrst);


	local_irq_disable();

	setbits32(&clk_r->car_plprcr, 0x00000080);
	/* Clear the ME bit in MSR to cause checkstop on machine check
	*/
	mtmsr(mfmsr() & ~0x1000);

	in_8(&clk_r->res[0]);
	panic("Restart failed\n");
}

static void cpm_cascade(unsigned int irq, struct irq_desc *desc)
{
	int cascade_irq;

	if ((cascade_irq = cpm_get_irq()) >= 0) {
		struct irq_desc *cdesc = irq_to_desc(cascade_irq);

		generic_handle_irq(cascade_irq);
		cdesc->chip->eoi(cascade_irq);
	}
	desc->chip->eoi(irq);
}

/* Initialize the internal interrupt controllers.  The number of
 * interrupts supported can vary with the processor type, and the
 * 82xx family can have up to 64.
 * External interrupts can be either edge or level triggered, and
 * need to be initialized by the appropriate driver.
 */
void __init mpc8xx_pics_init(void)
{
	int irq;

	if (mpc8xx_pic_init()) {
		printk(KERN_ERR "Failed interrupt 8xx controller  initialization\n");
		return;
	}

	irq = cpm_pic_init();
	if (irq != NO_IRQ)
		set_irq_chained_handler(irq, cpm_cascade);
}