Commit e6a9918c authored by Zachary Amsden's avatar Zachary Amsden Committed by Linus Torvalds
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[PATCH] x86: Fixed pnp bios limits 



PnP BIOS data, code, and 32-bit entry segments all have fixed limits as well;
set them in the GDT rather than adding more code.  It would be nice to add
these fixups to the boot GDT rather than setting the GDT for each CPU; perhaps
I can wiggle this in later, but getting it in before the subsys init looks
tricky.

Also, make some progress on deprecating the ugly Q_SET_SEL macros.

Signed-off-by: default avatarZachary Amsden <zach@vmware.com>
Cc: "Seth, Rohit" <rohit.seth@intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 5fe9fe3c

arch/i386/kernel/head.S

+8 −4
Original line number Diff line number Diff line
@@ -504,10 +504,14 @@ ENTRY(cpu_gdt_table) 
	.quad 0x0000000000000000	/* 0x80 TSS descriptor */

	.quad 0x0000000000000000	/* 0x88 LDT descriptor */



	/* Segments used for calling PnP BIOS have byte granularity */

	.quad 0x00409a0000000000	/* 0x90 32-bit code */

	.quad 0x00009a0000000000	/* 0x98 16-bit code */

	.quad 0x0000920000000000	/* 0xa0 16-bit data */

	/*

	 * Segments used for calling PnP BIOS have byte granularity.

	 * They code segments and data segments have fixed 64k limits,

	 * the transfer segment sizes are set at run time.

	 */

	.quad 0x00409a000000ffff	/* 0x90 32-bit code */

	.quad 0x00009a000000ffff	/* 0x98 16-bit code */

	.quad 0x000092000000ffff	/* 0xa0 16-bit data */

	.quad 0x0000920000000000	/* 0xa8 16-bit data */

	.quad 0x0000920000000000	/* 0xb0 16-bit data */

drivers/pnp/pnpbios/bioscalls.c

+4 −11
Original line number Diff line number Diff line
@@ -58,13 +58,6 @@ __asm__( 
	".previous		\n"

);



#define Q_SET_SEL(cpu, selname, address, size) \

do { \

struct desc_struct *gdt = get_cpu_gdt_table((cpu)); \

set_base(gdt[(selname) >> 3], __va((u32)(address))); \

set_limit(gdt[(selname) >> 3], size); \

} while(0)



#define Q2_SET_SEL(cpu, selname, address, size) \

do { \

struct desc_struct *gdt = get_cpu_gdt_table((cpu)); \
@@ -535,8 +528,8 @@ void pnpbios_calls_init(union pnp_bios_install_struct *header) 
  		struct desc_struct *gdt = get_cpu_gdt_table(i);

  		if (!gdt)

  			continue;

		Q2_SET_SEL(i, PNP_CS32, &pnp_bios_callfunc, 64 * 1024);

		Q_SET_SEL(i, PNP_CS16, header->fields.pm16cseg, 64 * 1024);

		Q_SET_SEL(i, PNP_DS, header->fields.pm16dseg, 64 * 1024);

 		set_base(gdt[GDT_ENTRY_PNPBIOS_CS32], &pnp_bios_callfunc);

 		set_base(gdt[GDT_ENTRY_PNPBIOS_CS16], __va(header->fields.pm16cseg));

 		set_base(gdt[GDT_ENTRY_PNPBIOS_DS], __va(header->fields.pm16dseg));

  	}

}

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