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authorPaul Mundt <lethal@linux-sh.org>2008-07-29 08:01:19 -0400
committerPaul Mundt <lethal@linux-sh.org>2008-07-29 08:01:19 -0400
commitda2014a2b080e7f3024a4eb6917d47069ad9620b (patch)
treecfde12c6d4b5baa222966b14a676f107992cf786 /arch/sh/boards/mach-dreamcast
parent71b8064e7df5698520d73b4c1566a3dbc98eb9ef (diff)
sh: Shuffle the board directories in to mach groups.
This flattens out the board directories in to individual mach groups, we will use this for getting rid of unneeded directories, simplifying the build system, and becoming more coherent with the refactored arch/sh/include topology. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Diffstat (limited to 'arch/sh/boards/mach-dreamcast')
-rw-r--r--arch/sh/boards/mach-dreamcast/Makefile6
-rw-r--r--arch/sh/boards/mach-dreamcast/irq.c153
-rw-r--r--arch/sh/boards/mach-dreamcast/rtc.c81
-rw-r--r--arch/sh/boards/mach-dreamcast/setup.c64
4 files changed, 304 insertions, 0 deletions
diff --git a/arch/sh/boards/mach-dreamcast/Makefile b/arch/sh/boards/mach-dreamcast/Makefile
new file mode 100644
index 000000000000..7b97546c7e5f
--- /dev/null
+++ b/arch/sh/boards/mach-dreamcast/Makefile
@@ -0,0 +1,6 @@
1#
2# Makefile for the Sega Dreamcast specific parts of the kernel
3#
4
5obj-y := setup.o irq.o rtc.o
6
diff --git a/arch/sh/boards/mach-dreamcast/irq.c b/arch/sh/boards/mach-dreamcast/irq.c
new file mode 100644
index 000000000000..67bdc33dd411
--- /dev/null
+++ b/arch/sh/boards/mach-dreamcast/irq.c
@@ -0,0 +1,153 @@
1/*
2 * arch/sh/boards/dreamcast/irq.c
3 *
4 * Holly IRQ support for the Sega Dreamcast.
5 *
6 * Copyright (c) 2001, 2002 M. R. Brown <mrbrown@0xd6.org>
7 *
8 * This file is part of the LinuxDC project (www.linuxdc.org)
9 * Released under the terms of the GNU GPL v2.0
10 */
11
12#include <linux/irq.h>
13#include <asm/io.h>
14#include <asm/irq.h>
15#include <mach/sysasic.h>
16
17/* Dreamcast System ASIC Hardware Events -
18
19 The Dreamcast's System ASIC (a.k.a. Holly) is responsible for receiving
20 hardware events from system peripherals and triggering an SH7750 IRQ.
21 Hardware events can trigger IRQs 13, 11, or 9 depending on which bits are
22 set in the Event Mask Registers (EMRs). When a hardware event is
23 triggered, it's corresponding bit in the Event Status Registers (ESRs)
24 is set, and that bit should be rewritten to the ESR to acknowledge that
25 event.
26
27 There are three 32-bit ESRs located at 0xa05f8900 - 0xa05f6908. Event
28 types can be found in include/asm-sh/dreamcast/sysasic.h. There are three
29 groups of EMRs that parallel the ESRs. Each EMR group corresponds to an
30 IRQ, so 0xa05f6910 - 0xa05f6918 triggers IRQ 13, 0xa05f6920 - 0xa05f6928
31 triggers IRQ 11, and 0xa05f6930 - 0xa05f6938 triggers IRQ 9.
32
33 In the kernel, these events are mapped to virtual IRQs so that drivers can
34 respond to them as they would a normal interrupt. In order to keep this
35 mapping simple, the events are mapped as:
36
37 6900/6910 - Events 0-31, IRQ 13
38 6904/6924 - Events 32-63, IRQ 11
39 6908/6938 - Events 64-95, IRQ 9
40
41*/
42
43#define ESR_BASE 0x005f6900 /* Base event status register */
44#define EMR_BASE 0x005f6910 /* Base event mask register */
45
46/* Helps us determine the EMR group that this event belongs to: 0 = 0x6910,
47 1 = 0x6920, 2 = 0x6930; also determine the event offset */
48#define LEVEL(event) (((event) - HW_EVENT_IRQ_BASE) / 32)
49
50/* Return the hardware event's bit positon within the EMR/ESR */
51#define EVENT_BIT(event) (((event) - HW_EVENT_IRQ_BASE) & 31)
52
53/* For each of these *_irq routines, the IRQ passed in is the virtual IRQ
54 (logically mapped to the corresponding bit for the hardware event). */
55
56/* Disable the hardware event by masking its bit in its EMR */
57static inline void disable_systemasic_irq(unsigned int irq)
58{
59 __u32 emr = EMR_BASE + (LEVEL(irq) << 4) + (LEVEL(irq) << 2);
60 __u32 mask;
61
62 mask = inl(emr);
63 mask &= ~(1 << EVENT_BIT(irq));
64 outl(mask, emr);
65}
66
67/* Enable the hardware event by setting its bit in its EMR */
68static inline void enable_systemasic_irq(unsigned int irq)
69{
70 __u32 emr = EMR_BASE + (LEVEL(irq) << 4) + (LEVEL(irq) << 2);
71 __u32 mask;
72
73 mask = inl(emr);
74 mask |= (1 << EVENT_BIT(irq));
75 outl(mask, emr);
76}
77
78/* Acknowledge a hardware event by writing its bit back to its ESR */
79static void ack_systemasic_irq(unsigned int irq)
80{
81 __u32 esr = ESR_BASE + (LEVEL(irq) << 2);
82 disable_systemasic_irq(irq);
83 outl((1 << EVENT_BIT(irq)), esr);
84}
85
86/* After a IRQ has been ack'd and responded to, it needs to be renabled */
87static void end_systemasic_irq(unsigned int irq)
88{
89 if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
90 enable_systemasic_irq(irq);
91}
92
93static unsigned int startup_systemasic_irq(unsigned int irq)
94{
95 enable_systemasic_irq(irq);
96
97 return 0;
98}
99
100static void shutdown_systemasic_irq(unsigned int irq)
101{
102 disable_systemasic_irq(irq);
103}
104
105struct hw_interrupt_type systemasic_int = {
106 .typename = "System ASIC",
107 .startup = startup_systemasic_irq,
108 .shutdown = shutdown_systemasic_irq,
109 .enable = enable_systemasic_irq,
110 .disable = disable_systemasic_irq,
111 .ack = ack_systemasic_irq,
112 .end = end_systemasic_irq,
113};
114
115/*
116 * Map the hardware event indicated by the processor IRQ to a virtual IRQ.
117 */
118int systemasic_irq_demux(int irq)
119{
120 __u32 emr, esr, status, level;
121 __u32 j, bit;
122
123 switch (irq) {
124 case 13:
125 level = 0;
126 break;
127 case 11:
128 level = 1;
129 break;
130 case 9:
131 level = 2;
132 break;
133 default:
134 return irq;
135 }
136 emr = EMR_BASE + (level << 4) + (level << 2);
137 esr = ESR_BASE + (level << 2);
138
139 /* Mask the ESR to filter any spurious, unwanted interrupts */
140 status = inl(esr);
141 status &= inl(emr);
142
143 /* Now scan and find the first set bit as the event to map */
144 for (bit = 1, j = 0; j < 32; bit <<= 1, j++) {
145 if (status & bit) {
146 irq = HW_EVENT_IRQ_BASE + j + (level << 5);
147 return irq;
148 }
149 }
150
151 /* Not reached */
152 return irq;
153}
diff --git a/arch/sh/boards/mach-dreamcast/rtc.c b/arch/sh/boards/mach-dreamcast/rtc.c
new file mode 100644
index 000000000000..a7433685798d
--- /dev/null
+++ b/arch/sh/boards/mach-dreamcast/rtc.c
@@ -0,0 +1,81 @@
1/*
2 * arch/sh/boards/dreamcast/rtc.c
3 *
4 * Dreamcast AICA RTC routines.
5 *
6 * Copyright (c) 2001, 2002 M. R. Brown <mrbrown@0xd6.org>
7 * Copyright (c) 2002 Paul Mundt <lethal@chaoticdreams.org>
8 *
9 * Released under the terms of the GNU GPL v2.0.
10 *
11 */
12
13#include <linux/time.h>
14#include <asm/rtc.h>
15#include <asm/io.h>
16
17/* The AICA RTC has an Epoch of 1/1/1950, so we must subtract 20 years (in
18 seconds) to get the standard Unix Epoch when getting the time, and add
19 20 years when setting the time. */
20#define TWENTY_YEARS ((20 * 365LU + 5) * 86400)
21
22/* The AICA RTC is represented by a 32-bit seconds counter stored in 2 16-bit
23 registers.*/
24#define AICA_RTC_SECS_H 0xa0710000
25#define AICA_RTC_SECS_L 0xa0710004
26
27/**
28 * aica_rtc_gettimeofday - Get the time from the AICA RTC
29 * @ts: pointer to resulting timespec
30 *
31 * Grabs the current RTC seconds counter and adjusts it to the Unix Epoch.
32 */
33static void aica_rtc_gettimeofday(struct timespec *ts)
34{
35 unsigned long val1, val2;
36
37 do {
38 val1 = ((ctrl_inl(AICA_RTC_SECS_H) & 0xffff) << 16) |
39 (ctrl_inl(AICA_RTC_SECS_L) & 0xffff);
40
41 val2 = ((ctrl_inl(AICA_RTC_SECS_H) & 0xffff) << 16) |
42 (ctrl_inl(AICA_RTC_SECS_L) & 0xffff);
43 } while (val1 != val2);
44
45 ts->tv_sec = val1 - TWENTY_YEARS;
46
47 /* Can't get nanoseconds with just a seconds counter. */
48 ts->tv_nsec = 0;
49}
50
51/**
52 * aica_rtc_settimeofday - Set the AICA RTC to the current time
53 * @secs: contains the time_t to set
54 *
55 * Adjusts the given @tv to the AICA Epoch and sets the RTC seconds counter.
56 */
57static int aica_rtc_settimeofday(const time_t secs)
58{
59 unsigned long val1, val2;
60 unsigned long adj = secs + TWENTY_YEARS;
61
62 do {
63 ctrl_outl((adj & 0xffff0000) >> 16, AICA_RTC_SECS_H);
64 ctrl_outl((adj & 0xffff), AICA_RTC_SECS_L);
65
66 val1 = ((ctrl_inl(AICA_RTC_SECS_H) & 0xffff) << 16) |
67 (ctrl_inl(AICA_RTC_SECS_L) & 0xffff);
68
69 val2 = ((ctrl_inl(AICA_RTC_SECS_H) & 0xffff) << 16) |
70 (ctrl_inl(AICA_RTC_SECS_L) & 0xffff);
71 } while (val1 != val2);
72
73 return 0;
74}
75
76void aica_time_init(void)
77{
78 rtc_sh_get_time = aica_rtc_gettimeofday;
79 rtc_sh_set_time = aica_rtc_settimeofday;
80}
81
diff --git a/arch/sh/boards/mach-dreamcast/setup.c b/arch/sh/boards/mach-dreamcast/setup.c
new file mode 100644
index 000000000000..7d944fc75e93
--- /dev/null
+++ b/arch/sh/boards/mach-dreamcast/setup.c
@@ -0,0 +1,64 @@
1/*
2 * arch/sh/boards/dreamcast/setup.c
3 *
4 * Hardware support for the Sega Dreamcast.
5 *
6 * Copyright (c) 2001, 2002 M. R. Brown <mrbrown@linuxdc.org>
7 * Copyright (c) 2002, 2003, 2004 Paul Mundt <lethal@linux-sh.org>
8 *
9 * This file is part of the LinuxDC project (www.linuxdc.org)
10 *
11 * Released under the terms of the GNU GPL v2.0.
12 *
13 * This file originally bore the message (with enclosed-$):
14 * Id: setup_dc.c,v 1.5 2001/05/24 05:09:16 mrbrown Exp
15 * SEGA Dreamcast support
16 */
17
18#include <linux/sched.h>
19#include <linux/kernel.h>
20#include <linux/param.h>
21#include <linux/interrupt.h>
22#include <linux/init.h>
23#include <linux/irq.h>
24#include <linux/device.h>
25#include <asm/io.h>
26#include <asm/irq.h>
27#include <asm/rtc.h>
28#include <asm/machvec.h>
29#include <mach/sysasic.h>
30
31extern struct hw_interrupt_type systemasic_int;
32extern void aica_time_init(void);
33extern int gapspci_init(void);
34extern int systemasic_irq_demux(int);
35
36static void __init dreamcast_setup(char **cmdline_p)
37{
38 int i;
39
40 /* Mask all hardware events */
41 /* XXX */
42
43 /* Acknowledge any previous events */
44 /* XXX */
45
46 __set_io_port_base(0xa0000000);
47
48 /* Assign all virtual IRQs to the System ASIC int. handler */
49 for (i = HW_EVENT_IRQ_BASE; i < HW_EVENT_IRQ_MAX; i++)
50 irq_desc[i].chip = &systemasic_int;
51
52 board_time_init = aica_time_init;
53
54#ifdef CONFIG_PCI
55 if (gapspci_init() < 0)
56 printk(KERN_WARNING "GAPSPCI was not detected.\n");
57#endif
58}
59
60static struct sh_machine_vector mv_dreamcast __initmv = {
61 .mv_name = "Sega Dreamcast",
62 .mv_setup = dreamcast_setup,
63 .mv_irq_demux = systemasic_irq_demux,
64};