add directory bochs

bochs/README_FIRST

@@ -0,0 +1,42 @@
+Problem when run with the newer Bochs software and fixing methods
+-----------------------------------------------------------------
+gohigh@sh163.net, gohigh@gmail.com
+2006.08.28
+
+
+When running the Linux kernel 0.1x in Bochs environment with version number
+newer or equal to 2.2.6, you may encounter an problem at the bootstrap period
+with the error message "HD controller not ready". There are two general 
+methods you can use to fix this problem. 
+
+1. One way is tricky but easy and without modify the kernel code. you need 
+only copy the harddisk image file to another name and modify the .bxrc file
+to attach it as a second or slave hd in it. Fox example, if you have a hard
+disk image file with name is hdc-0.11.img, just copy it to produce another 
+disk image with a name something like hdd-0.11.img. Then modify 
+the corresponding configuration file, for example, bochsrc-hd.bxrc. Add the 
+following line, and the parameters in the line should be the same with your
+hdc-0.11.img line. Then you can go with the newer bochs system.
+
+ata0-slave: type=disk, path="hdd-0.11.img", mode=flat, cylinders=410, heads=16, spt=38
+
+
+2. The second mothod is to modify the linux/kernel/blk_drv/hd.c file in you 
+Linux kernel 0.11. Change the code at line 163 and 165:
+
+163 int retries=10000;
+164
+165 while (--retries && (inb_p(HD_STATUS)&0xc0)!=0x40); 
+
+as following:
+
+163int retries=100000;
+164
+165while (--retries && (inb_p(HD_STATUS)&0x80)); 
+
+then rebuild the kernel and write it to the boot floppy image file:
+
+dd if=Image of=/dev/fd0
+
+
+(End)