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authorPaul Mundt <lethal@linux-sh.org>2008-07-29 21:01:19 +0900
committerPaul Mundt <lethal@linux-sh.org>2008-07-29 21:01:19 +0900
commitda2014a2b080e7f3024a4eb6917d47069ad9620b (patch)
treecfde12c6d4b5baa222966b14a676f107992cf786 /arch/sh/boards/mach-dreamcast
parent71b8064e7df5698520d73b4c1566a3dbc98eb9ef (diff)
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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 0000000..7b97546
--- /dev/null
+++ b/arch/sh/boards/mach-dreamcast/Makefile
@@ -0,0 +1,6 @@
+#
+# Makefile for the Sega Dreamcast specific parts of the kernel
+#
+
+obj-y := setup.o irq.o rtc.o
+
diff --git a/arch/sh/boards/mach-dreamcast/irq.c b/arch/sh/boards/mach-dreamcast/irq.c
new file mode 100644
index 0000000..67bdc33
--- /dev/null
+++ b/arch/sh/boards/mach-dreamcast/irq.c
@@ -0,0 +1,153 @@
+/*
+ * arch/sh/boards/dreamcast/irq.c
+ *
+ * Holly IRQ support for the Sega Dreamcast.
+ *
+ * Copyright (c) 2001, 2002 M. R. Brown <mrbrown@0xd6.org>
+ *
+ * This file is part of the LinuxDC project (www.linuxdc.org)
+ * Released under the terms of the GNU GPL v2.0
+ */
+
+#include <linux/irq.h>
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <mach/sysasic.h>
+
+/* Dreamcast System ASIC Hardware Events -
+
+ The Dreamcast's System ASIC (a.k.a. Holly) is responsible for receiving
+ hardware events from system peripherals and triggering an SH7750 IRQ.
+ Hardware events can trigger IRQs 13, 11, or 9 depending on which bits are
+ set in the Event Mask Registers (EMRs). When a hardware event is
+ triggered, it's corresponding bit in the Event Status Registers (ESRs)
+ is set, and that bit should be rewritten to the ESR to acknowledge that
+ event.
+
+ There are three 32-bit ESRs located at 0xa05f8900 - 0xa05f6908. Event
+ types can be found in include/asm-sh/dreamcast/sysasic.h. There are three
+ groups of EMRs that parallel the ESRs. Each EMR group corresponds to an
+ IRQ, so 0xa05f6910 - 0xa05f6918 triggers IRQ 13, 0xa05f6920 - 0xa05f6928
+ triggers IRQ 11, and 0xa05f6930 - 0xa05f6938 triggers IRQ 9.
+
+ In the kernel, these events are mapped to virtual IRQs so that drivers can
+ respond to them as they would a normal interrupt. In order to keep this
+ mapping simple, the events are mapped as:
+
+ 6900/6910 - Events 0-31, IRQ 13
+ 6904/6924 - Events 32-63, IRQ 11
+ 6908/6938 - Events 64-95, IRQ 9
+
+*/
+
+#define ESR_BASE 0x005f6900 /* Base event status register */
+#define EMR_BASE 0x005f6910 /* Base event mask register */
+
+/* Helps us determine the EMR group that this event belongs to: 0 = 0x6910,
+ 1 = 0x6920, 2 = 0x6930; also determine the event offset */
+#define LEVEL(event) (((event) - HW_EVENT_IRQ_BASE) / 32)
+
+/* Return the hardware event's bit positon within the EMR/ESR */
+#define EVENT_BIT(event) (((event) - HW_EVENT_IRQ_BASE) & 31)
+
+/* For each of these *_irq routines, the IRQ passed in is the virtual IRQ
+ (logically mapped to the corresponding bit for the hardware event). */
+
+/* Disable the hardware event by masking its bit in its EMR */
+static inline void disable_systemasic_irq(unsigned int irq)
+{
+ __u32 emr = EMR_BASE + (LEVEL(irq) << 4) + (LEVEL(irq) << 2);
+ __u32 mask;
+
+ mask = inl(emr);
+ mask &= ~(1 << EVENT_BIT(irq));
+ outl(mask, emr);
+}
+
+/* Enable the hardware event by setting its bit in its EMR */
+static inline void enable_systemasic_irq(unsigned int irq)
+{
+ __u32 emr = EMR_BASE + (LEVEL(irq) << 4) + (LEVEL(irq) << 2);
+ __u32 mask;
+
+ mask = inl(emr);
+ mask |= (1 << EVENT_BIT(irq));
+ outl(mask, emr);
+}
+
+/* Acknowledge a hardware event by writing its bit back to its ESR */
+static void ack_systemasic_irq(unsigned int irq)
+{
+ __u32 esr = ESR_BASE + (LEVEL(irq) << 2);
+ disable_systemasic_irq(irq);
+ outl((1 << EVENT_BIT(irq)), esr);
+}
+
+/* After a IRQ has been ack'd and responded to, it needs to be renabled */
+static void end_systemasic_irq(unsigned int irq)
+{
+ if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
+ enable_systemasic_irq(irq);
+}
+
+static unsigned int startup_systemasic_irq(unsigned int irq)
+{
+ enable_systemasic_irq(irq);
+
+ return 0;
+}
+
+static void shutdown_systemasic_irq(unsigned int irq)
+{
+ disable_systemasic_irq(irq);
+}
+
+struct hw_interrupt_type systemasic_int = {
+ .typename = "System ASIC",
+ .startup = startup_systemasic_irq,
+ .shutdown = shutdown_systemasic_irq,
+ .enable = enable_systemasic_irq,
+ .disable = disable_systemasic_irq,
+ .ack = ack_systemasic_irq,
+ .end = end_systemasic_irq,
+};
+
+/*
+ * Map the hardware event indicated by the processor IRQ to a virtual IRQ.
+ */
+int systemasic_irq_demux(int irq)
+{
+ __u32 emr, esr, status, level;
+ __u32 j, bit;
+
+ switch (irq) {
+ case 13:
+ level = 0;
+ break;
+ case 11:
+ level = 1;
+ break;
+ case 9:
+ level = 2;
+ break;
+ default:
+ return irq;
+ }
+ emr = EMR_BASE + (level << 4) + (level << 2);
+ esr = ESR_BASE + (level << 2);
+
+ /* Mask the ESR to filter any spurious, unwanted interrupts */
+ status = inl(esr);
+ status &= inl(emr);
+
+ /* Now scan and find the first set bit as the event to map */
+ for (bit = 1, j = 0; j < 32; bit <<= 1, j++) {
+ if (status & bit) {
+ irq = HW_EVENT_IRQ_BASE + j + (level << 5);
+ return irq;
+ }
+ }
+
+ /* Not reached */
+ return irq;
+}
diff --git a/arch/sh/boards/mach-dreamcast/rtc.c b/arch/sh/boards/mach-dreamcast/rtc.c
new file mode 100644
index 0000000..a743368
--- /dev/null
+++ b/arch/sh/boards/mach-dreamcast/rtc.c
@@ -0,0 +1,81 @@
+/*
+ * arch/sh/boards/dreamcast/rtc.c
+ *
+ * Dreamcast AICA RTC routines.
+ *
+ * Copyright (c) 2001, 2002 M. R. Brown <mrbrown@0xd6.org>
+ * Copyright (c) 2002 Paul Mundt <lethal@chaoticdreams.org>
+ *
+ * Released under the terms of the GNU GPL v2.0.
+ *
+ */
+
+#include <linux/time.h>
+#include <asm/rtc.h>
+#include <asm/io.h>
+
+/* The AICA RTC has an Epoch of 1/1/1950, so we must subtract 20 years (in
+ seconds) to get the standard Unix Epoch when getting the time, and add
+ 20 years when setting the time. */
+#define TWENTY_YEARS ((20 * 365LU + 5) * 86400)
+
+/* The AICA RTC is represented by a 32-bit seconds counter stored in 2 16-bit
+ registers.*/
+#define AICA_RTC_SECS_H 0xa0710000
+#define AICA_RTC_SECS_L 0xa0710004
+
+/**
+ * aica_rtc_gettimeofday - Get the time from the AICA RTC
+ * @ts: pointer to resulting timespec
+ *
+ * Grabs the current RTC seconds counter and adjusts it to the Unix Epoch.
+ */
+static void aica_rtc_gettimeofday(struct timespec *ts)
+{
+ unsigned long val1, val2;
+
+ do {
+ val1 = ((ctrl_inl(AICA_RTC_SECS_H) & 0xffff) << 16) |
+ (ctrl_inl(AICA_RTC_SECS_L) & 0xffff);
+
+ val2 = ((ctrl_inl(AICA_RTC_SECS_H) & 0xffff) << 16) |
+ (ctrl_inl(AICA_RTC_SECS_L) & 0xffff);
+ } while (val1 != val2);
+
+ ts->tv_sec = val1 - TWENTY_YEARS;
+
+ /* Can't get nanoseconds with just a seconds counter. */
+ ts->tv_nsec = 0;
+}
+
+/**
+ * aica_rtc_settimeofday - Set the AICA RTC to the current time
+ * @secs: contains the time_t to set
+ *
+ * Adjusts the given @tv to the AICA Epoch and sets the RTC seconds counter.
+ */
+static int aica_rtc_settimeofday(const time_t secs)
+{
+ unsigned long val1, val2;
+ unsigned long adj = secs + TWENTY_YEARS;
+
+ do {
+ ctrl_outl((adj & 0xffff0000) >> 16, AICA_RTC_SECS_H);
+ ctrl_outl((adj & 0xffff), AICA_RTC_SECS_L);
+
+ val1 = ((ctrl_inl(AICA_RTC_SECS_H) & 0xffff) << 16) |
+ (ctrl_inl(AICA_RTC_SECS_L) & 0xffff);
+
+ val2 = ((ctrl_inl(AICA_RTC_SECS_H) & 0xffff) << 16) |
+ (ctrl_inl(AICA_RTC_SECS_L) & 0xffff);
+ } while (val1 != val2);
+
+ return 0;
+}
+
+void aica_time_init(void)
+{
+ rtc_sh_get_time = aica_rtc_gettimeofday;
+ rtc_sh_set_time = aica_rtc_settimeofday;
+}
+
diff --git a/arch/sh/boards/mach-dreamcast/setup.c b/arch/sh/boards/mach-dreamcast/setup.c
new file mode 100644
index 0000000..7d944fc
--- /dev/null
+++ b/arch/sh/boards/mach-dreamcast/setup.c
@@ -0,0 +1,64 @@
+/*
+ * arch/sh/boards/dreamcast/setup.c
+ *
+ * Hardware support for the Sega Dreamcast.
+ *
+ * Copyright (c) 2001, 2002 M. R. Brown <mrbrown@linuxdc.org>
+ * Copyright (c) 2002, 2003, 2004 Paul Mundt <lethal@linux-sh.org>
+ *
+ * This file is part of the LinuxDC project (www.linuxdc.org)
+ *
+ * Released under the terms of the GNU GPL v2.0.
+ *
+ * This file originally bore the message (with enclosed-$):
+ * Id: setup_dc.c,v 1.5 2001/05/24 05:09:16 mrbrown Exp
+ * SEGA Dreamcast support
+ */
+
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/param.h>
+#include <linux/interrupt.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/device.h>
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/rtc.h>
+#include <asm/machvec.h>
+#include <mach/sysasic.h>
+
+extern struct hw_interrupt_type systemasic_int;
+extern void aica_time_init(void);
+extern int gapspci_init(void);
+extern int systemasic_irq_demux(int);
+
+static void __init dreamcast_setup(char **cmdline_p)
+{
+ int i;
+
+ /* Mask all hardware events */
+ /* XXX */
+
+ /* Acknowledge any previous events */
+ /* XXX */
+
+ __set_io_port_base(0xa0000000);
+
+ /* Assign all virtual IRQs to the System ASIC int. handler */
+ for (i = HW_EVENT_IRQ_BASE; i < HW_EVENT_IRQ_MAX; i++)
+ irq_desc[i].chip = &systemasic_int;
+
+ board_time_init = aica_time_init;
+
+#ifdef CONFIG_PCI
+ if (gapspci_init() < 0)
+ printk(KERN_WARNING "GAPSPCI was not detected.\n");
+#endif
+}
+
+static struct sh_machine_vector mv_dreamcast __initmv = {
+ .mv_name = "Sega Dreamcast",
+ .mv_setup = dreamcast_setup,
+ .mv_irq_demux = systemasic_irq_demux,
+};