Import and compile code for article 6.5

1 files changed, 97 insertions, 0 deletions

diff --git a/sos-code-article6.5/hwcore/irq.h b/sos-code-article6.5/hwcore/irq.h
new file mode 100644
index 0000000..c067cc4
--- /dev/null
+++ b/sos-code-article6.5/hwcore/irq.h
@@ -0,0 +1,97 @@
+/* Copyright (C) 2004  David Decotigny
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License
+   as published by the Free Software Foundation; either version 2
+   of the License, or (at your option) any later version.
+   
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+   
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
+   USA. 
+*/
+#ifndef _SOS_HWINTR_H_
+#define _SOS_HWINTR_H_
+
+
+/**
+ * @file irq.c
+ *
+ * Hardware interrupts routines management.
+ */
+
+
+#include <sos/errno.h>
+#include "cpu_context.h"
+
+
+#define sos_save_flags(flags) \
+  asm volatile("pushfl ; popl %0":"=g"(flags)::"memory")
+#define sos_restore_flags(flags) \
+  asm volatile("push %0; popfl"::"g"(flags):"memory")
+
+
+#define sos_disable_IRQs(flags)    \
+  ({ sos_save_flags(flags); asm("cli\n"); })
+#define sos_restore_IRQs(flags)    \
+  sos_restore_flags(flags)
+
+
+/* Usual IRQ levels */
+#define SOS_IRQ_TIMER         0
+#define SOS_IRQ_KEYBOARD      1
+#define SOS_IRQ_SLAVE_PIC     2
+#define SOS_IRQ_COM2          3
+#define SOS_IRQ_COM1          4
+#define SOS_IRQ_LPT2          5
+#define SOS_IRQ_FLOPPY        6
+#define SOS_IRQ_LPT1          7
+#define SOS_IRQ_8_NOT_DEFINED 8
+#define SOS_IRQ_RESERVED_1    9
+#define SOS_IRQ_RESERVED_2    10
+#define SOS_IRQ_RESERVED_3    11
+#define SOS_IRQ_RESERVED_4    12
+#define SOS_IRQ_COPROCESSOR   13
+#define SOS_IRQ_HARDDISK      14
+#define SOS_IRQ_RESERVED_5    15
+
+
+/** Definition of an hardware IRQ handler */
+typedef void (*sos_irq_handler_t)(int irq_level);
+
+
+/** Setup the PIC */
+sos_ret_t sos_irq_subsystem_setup(void);
+
+
+/**
+ * If the routine is not NULL, the IDT is setup to call an IRQ
+ * wrapper upon interrupt, which in turn will call the routine, and
+ * the PIC is programmed to raise an irq.\ If the routine is
+ * NULL, we disable the irq line.
+ */
+sos_ret_t sos_irq_set_routine(int irq_level,
+			      sos_irq_handler_t routine);
+
+sos_irq_handler_t sos_irq_get_routine(int irq_level);
+
+
+/**
+ * Tell how many nested IRQ handler have been fired
+ */
+sos_ui32_t sos_irq_get_nested_level();
+
+
+/**
+ * Return TRUE when we are currently executing in interrupt context
+ */
+#define sos_servicing_irq() \
+  (sos_irq_get_nested_level() > 0)
+
+
+#endif /* _SOS_HWINTR_H_ */