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Instead of all of this cpu-specific code to remap the kernel
to the correct location, use portable firmware calls to do
this instead.
What we do now is the following in position independant
assembler:
chosen_node = prom_finddevice("/chosen");
prom_mmu_ihandle_cache = prom_getint(chosen_node, "mmu");
vaddr = 4MB_ALIGN(current_text_addr());
prom_translate(vaddr, &paddr_high, &paddr_low, &mode);
prom_boot_mapping_mode = mode;
prom_boot_mapping_phys_high = paddr_high;
prom_boot_mapping_phys_low = paddr_low;
prom_map(-1, 8 * 1024 * 1024, KERNBASE, paddr_low);
and that replaces the massive amount of by-hand TLB probing and
programming we used to do here.
The new code should also handle properly the case where the kernel
is mapped at the correct address already (think: future kexec
support).
Consequently, the bulk of remap_kernel() dies as does the entirety
of arch/sparc64/prom/map.S
We try to share some strings in the PROM library with the ones used
at bootup, and while we're here mark input strings to oplib.h routines
with "const" when appropriate.
There are many more simplifications now possible. For one thing, we
can consolidate the two copies we now have of a lot of cpu setup code
sitting in head.S and trampoline.S.
This is a significant step towards CONFIG_DEBUG_PAGEALLOC support.
Signed-off-by: David S. Miller <davem@davemloft.net>
42 lines
1.0 KiB
C
42 lines
1.0 KiB
C
/* $Id: devops.c,v 1.3 1997/10/29 07:43:28 ecd Exp $
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* devops.c: Device operations using the PROM.
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*
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* Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
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* Copyright (C) 1996,1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
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*/
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#include <linux/types.h>
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#include <linux/kernel.h>
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#include <linux/sched.h>
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#include <asm/openprom.h>
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#include <asm/oplib.h>
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/* Open the device described by the string 'dstr'. Returns the handle
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* to that device used for subsequent operations on that device.
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* Returns 0 on failure.
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*/
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int
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prom_devopen(const char *dstr)
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{
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return p1275_cmd ("open", P1275_ARG(0,P1275_ARG_IN_STRING)|
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P1275_INOUT(1,1),
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dstr);
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}
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/* Close the device described by device handle 'dhandle'. */
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int
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prom_devclose(int dhandle)
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{
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p1275_cmd ("close", P1275_INOUT(1,0), dhandle);
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return 0;
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}
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/* Seek to specified location described by 'seekhi' and 'seeklo'
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* for device 'dhandle'.
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*/
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void
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prom_seek(int dhandle, unsigned int seekhi, unsigned int seeklo)
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{
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p1275_cmd ("seek", P1275_INOUT(3,1), dhandle, seekhi, seeklo);
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}
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