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/* Copyright (C) 2004 The SOS Team
Copyright (C) 1999 Free Software Foundation, Inc.
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.
*/
/* Include definitions of the multiboot standard */
#include <bootstrap/multiboot.h>
#include <hwcore/idt.h>
#include <hwcore/gdt.h>
#include <hwcore/irq.h>
#include <hwcore/exception.h>
#include <hwcore/i8254.h>
#include <sos/list.h>
#include <sos/physmem.h>
#include <sos/klibc.h>
#include <sos/assert.h>
#include <drivers/x86_videomem.h>
#include <drivers/bochs.h>
/* Helper function to display each bits of a 32bits integer on the
screen as dark or light carrets */
static void display_bits(unsigned char row, unsigned char col,
unsigned char attribute,
sos_ui32_t integer)
{
int i;
/* Scan each bit of the integer, MSb first */
for (i = 31 ; i >= 0 ; i--)
{
/* Test if bit i of 'integer' is set */
int bit_i = (integer & (1 << i));
/* Ascii 219 => dark carret, Ascii 177 => light carret */
unsigned char ascii_code = bit_i?219:177;
sos_x86_videomem_putchar(row, col++,
attribute,
ascii_code);
}
}
/* Clock IRQ handler */
static void clk_it(int intid)
{
static sos_ui32_t clock_count = 0;
display_bits(0, 48,
SOS_X86_VIDEO_FG_LTGREEN | SOS_X86_VIDEO_BG_BLUE,
clock_count);
clock_count++;
}
#define MY_PPAGE_NUM_INT 511
struct my_ppage
{
sos_ui32_t before[MY_PPAGE_NUM_INT];
struct my_ppage *prev, *next;
sos_ui32_t after[MY_PPAGE_NUM_INT];
}; /* sizeof() Must be <= 4kB */
static void test_physmem()
{
/* We place the pages we did allocate here */
struct my_ppage *ppage_list, *my_ppage;
sos_count_t num_alloc_ppages = 0, num_free_ppages = 0;
ppage_list = NULL;
while ((my_ppage = (struct my_ppage*)sos_physmem_ref_physpage_new(FALSE))
!= NULL)
{
int i;
num_alloc_ppages++;
/* Print the allocation status */
sos_x86_videomem_printf(2, 0,
SOS_X86_VIDEO_FG_YELLOW
| SOS_X86_VIDEO_BG_BLUE,
"Could allocate %d pages ",
num_alloc_ppages);
/* We fill this page with its address */
for (i = 0 ; i < MY_PPAGE_NUM_INT ; i++)
my_ppage->before[i] = my_ppage->after[i] = (sos_ui32_t)my_ppage;
/* We add this page at the tail of our list of ppages */
list_add_tail(ppage_list, my_ppage);
}
/* Now we release these pages in FIFO order */
while ((my_ppage = list_pop_head(ppage_list)) != NULL)
{
/* We make sure this page was not overwritten by any unexpected
value */
int i;
for (i = 0 ; i < MY_PPAGE_NUM_INT ; i++)
{
/* We don't get what we expect ! */
if ((my_ppage->before[i] != (sos_ui32_t)my_ppage)
|| (my_ppage->after[i] != (sos_ui32_t)my_ppage))
{
/* STOP ! */
sos_x86_videomem_putstring(20, 0,
SOS_X86_VIDEO_FG_LTRED
| SOS_X86_VIDEO_BG_BLUE,
"Page overwritten");
return;
}
}
/* Release the descriptor */
if (sos_physmem_unref_physpage((sos_paddr_t)my_ppage) < 0)
{
/* STOP ! */
sos_x86_videomem_putstring(20, 0,
SOS_X86_VIDEO_FG_LTRED
| SOS_X86_VIDEO_BG_BLUE,
"Cannot release page");
return;
}
/* Print the deallocation status */
num_free_ppages ++;
sos_x86_videomem_printf(2, 0,
SOS_X86_VIDEO_FG_YELLOW
| SOS_X86_VIDEO_BG_BLUE,
"Could free %d pages ",
num_free_ppages);
}
/* Print the overall stats */
sos_x86_videomem_printf(2, 0,
SOS_X86_VIDEO_FG_LTGREEN
| SOS_X86_VIDEO_BG_BLUE,
"Could allocate %d bytes, could free %d bytes ",
num_alloc_ppages << SOS_PAGE_SHIFT,
num_free_ppages << SOS_PAGE_SHIFT);
SOS_ASSERT_FATAL(num_alloc_ppages == num_free_ppages);
}
/* The C entry point of our operating system */
void sos_main(unsigned long magic, unsigned long addr)
{
unsigned i;
sos_paddr_t sos_kernel_core_base_paddr, sos_kernel_core_top_paddr;
/* Grub sends us a structure, called multiboot_info_t with a lot of
precious informations about the system, see the multiboot
documentation for more information. */
multiboot_info_t *mbi;
mbi = (multiboot_info_t *) addr;
/* Setup bochs and console, and clear the console */
sos_bochs_setup();
sos_x86_videomem_setup();
sos_x86_videomem_cls(SOS_X86_VIDEO_BG_BLUE);
/* Greetings from SOS */
if (magic == MULTIBOOT_BOOTLOADER_MAGIC)
/* Loaded with Grub */
sos_x86_videomem_printf(1, 0,
SOS_X86_VIDEO_FG_YELLOW | SOS_X86_VIDEO_BG_BLUE,
"Welcome From GRUB to %s%c RAM is %dMB (upper mem = 0x%x kB)",
"SOS", ',',
(unsigned)(mbi->mem_upper >> 10) + 1,
(unsigned)mbi->mem_upper);
else
/* Not loaded with grub */
sos_x86_videomem_printf(1, 0,
SOS_X86_VIDEO_FG_YELLOW | SOS_X86_VIDEO_BG_BLUE,
"Welcome to SOS");
sos_bochs_putstring("Message in a bochs\n");
/* Setup CPU segmentation and IRQ subsystem */
sos_gdt_setup();
sos_idt_setup();
/* Setup SOS IRQs and exceptions subsystem */
sos_exceptions_setup();
sos_irq_setup();
/* Configure the timer so as to raise the IRQ0 at a 100Hz rate */
sos_i8254_set_frequency(100);
/* We need a multiboot-compliant boot loader to get the size of the RAM */
if (magic != MULTIBOOT_BOOTLOADER_MAGIC)
{
sos_x86_videomem_putstring(20, 0,
SOS_X86_VIDEO_FG_LTRED
| SOS_X86_VIDEO_BG_BLUE
| SOS_X86_VIDEO_FG_BLINKING,
"I'm not loaded with Grub !");
/* STOP ! */
for (;;)
continue;
}
/* Binding some HW interrupts and exceptions to software routines */
sos_irq_set_routine(SOS_IRQ_TIMER,
clk_it);
/* Enabling the HW interrupts here, this will make the timer HW
interrupt call our clk_it handler */
asm volatile ("sti\n");
/* Multiboot says: "The value returned for upper memory is maximally
the address of the first upper memory hole minus 1 megabyte.". It
also adds: "It is not guaranteed to be this value." aka "YMMV" ;) */
sos_physmem_setup((mbi->mem_upper<<10) + (1<<20),
& sos_kernel_core_base_paddr,
& sos_kernel_core_top_paddr);
test_physmem();
/* An operatig system never ends */
for (;;)
continue;
return;
}
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