Christophe Leroy 63f501e07a powerpc/8xx: Simplify TLB handling
In the old days, TLB handling for 8xx was using tlbie and tlbia
instructions directly as much as possible.

But commit f048aace29e0 ("powerpc/mm: Add SMP support to no-hash
TLB handling") broke that by introducing out-of-line unnecessary
complex functions for booke/smp which don't have tlbie/tlbia
instructions and require more complex handling.

Restore direct use of tlbie and tlbia for 8xx which is never SMP.

With this patch we now get

	c00ecc68 <ptep_clear_flush>:
	c00ecc68:	39 00 00 00 	li      r8,0
	c00ecc6c:	81 46 00 00 	lwz     r10,0(r6)
	c00ecc70:	91 06 00 00 	stw     r8,0(r6)
	c00ecc74:	7c 00 2a 64 	tlbie   r5,r0
	c00ecc78:	7c 00 04 ac 	hwsync
	c00ecc7c:	91 43 00 00 	stw     r10,0(r3)
	c00ecc80:	4e 80 00 20 	blr

Before it was

	c0012880 <local_flush_tlb_page>:
	c0012880:	2c 03 00 00 	cmpwi   r3,0
	c0012884:	41 82 00 54 	beq     c00128d8 <local_flush_tlb_page+0x58>
	c0012888:	81 22 00 00 	lwz     r9,0(r2)
	c001288c:	81 43 00 20 	lwz     r10,32(r3)
	c0012890:	39 29 00 01 	addi    r9,r9,1
	c0012894:	91 22 00 00 	stw     r9,0(r2)
	c0012898:	2c 0a 00 00 	cmpwi   r10,0
	c001289c:	41 82 00 10 	beq     c00128ac <local_flush_tlb_page+0x2c>
	c00128a0:	81 2a 01 dc 	lwz     r9,476(r10)
	c00128a4:	2c 09 ff ff 	cmpwi   r9,-1
	c00128a8:	41 82 00 0c 	beq     c00128b4 <local_flush_tlb_page+0x34>
	c00128ac:	7c 00 22 64 	tlbie   r4,r0
	c00128b0:	7c 00 04 ac 	hwsync
	c00128b4:	81 22 00 00 	lwz     r9,0(r2)
	c00128b8:	39 29 ff ff 	addi    r9,r9,-1
	c00128bc:	2c 09 00 00 	cmpwi   r9,0
	c00128c0:	91 22 00 00 	stw     r9,0(r2)
	c00128c4:	4c a2 00 20 	bclr+   4,eq
	c00128c8:	81 22 00 70 	lwz     r9,112(r2)
	c00128cc:	71 29 00 04 	andi.   r9,r9,4
	c00128d0:	4d 82 00 20 	beqlr
	c00128d4:	48 65 76 74 	b       c0669f48 <preempt_schedule>
	c00128d8:	81 22 00 00 	lwz     r9,0(r2)
	c00128dc:	39 29 00 01 	addi    r9,r9,1
	c00128e0:	91 22 00 00 	stw     r9,0(r2)
	c00128e4:	4b ff ff c8 	b       c00128ac <local_flush_tlb_page+0x2c>
...
	c00ecdc8 <ptep_clear_flush>:
	c00ecdc8:	94 21 ff f0 	stwu    r1,-16(r1)
	c00ecdcc:	39 20 00 00 	li      r9,0
	c00ecdd0:	93 c1 00 08 	stw     r30,8(r1)
	c00ecdd4:	83 c6 00 00 	lwz     r30,0(r6)
	c00ecdd8:	91 26 00 00 	stw     r9,0(r6)
	c00ecddc:	93 e1 00 0c 	stw     r31,12(r1)
	c00ecde0:	7c 08 02 a6 	mflr    r0
	c00ecde4:	7c 7f 1b 78 	mr      r31,r3
	c00ecde8:	7c 83 23 78 	mr      r3,r4
	c00ecdec:	7c a4 2b 78 	mr      r4,r5
	c00ecdf0:	90 01 00 14 	stw     r0,20(r1)
	c00ecdf4:	4b f2 5a 8d 	bl      c0012880 <local_flush_tlb_page>
	c00ecdf8:	93 df 00 00 	stw     r30,0(r31)
	c00ecdfc:	7f e3 fb 78 	mr      r3,r31
	c00ece00:	80 01 00 14 	lwz     r0,20(r1)
	c00ece04:	83 c1 00 08 	lwz     r30,8(r1)
	c00ece08:	83 e1 00 0c 	lwz     r31,12(r1)
	c00ece0c:	7c 08 03 a6 	mtlr    r0
	c00ece10:	38 21 00 10 	addi    r1,r1,16
	c00ece14:	4e 80 00 20 	blr

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/fb324f1c8f2ddb57cf6aad1cea26329558f1c1c0.1631887021.git.christophe.leroy@csgroup.eu
2021-10-22 15:22:05 +11:00
2021-10-22 15:22:05 +11:00
2021-09-17 09:23:44 -07:00
2021-09-07 12:08:04 -07:00
2021-09-19 12:55:12 -07:00
2021-09-03 15:33:47 -07:00
2021-09-09 16:05:10 -07:00
2021-09-19 13:00:23 -07:00
2021-09-19 17:28:22 -07:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
Description
No description provided
Readme 5.7 GiB
Languages
C 97.6%
Assembly 1%
Shell 0.5%
Python 0.3%
Makefile 0.3%