Differential D14647 Diff 40247 head/sys/powerpc/ofw/ofwcall64.S

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head/sys/powerpc/ofw/ofwcall64.S

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/*		/*
* Globals		* Globals
*/		*/
.data		.data
.align 4		.align 4
ofwstk:		ofwstk:
.space OFWSTKSZ		.space OFWSTKSZ
rtas_regsave:		rtas_regsave:
.space 24 /* 3 * sizeof(register_t) */		.space 32 /* 4 * sizeof(register_t) */
GLOBAL(ofmsr)		GLOBAL(ofmsr)
.llong 0, 0, 0, 0, 0 /* msr/sprg0-3 used in Open Firmware */		.llong 0, 0, 0, 0, 0 /* msr/sprg0-3 used in Open Firmware */
GLOBAL(rtasmsr)		GLOBAL(rtasmsr)
.llong 0		.llong 0
GLOBAL(openfirmware_entry)		GLOBAL(openfirmware_entry)
.llong 0 /* Open Firmware entry point */		.llong 0 /* Open Firmware entry point */
GLOBAL(rtas_entry)		GLOBAL(rtas_entry)
.llong 0 /* RTAS entry point */		.llong 0 /* RTAS entry point */

TOC_ENTRY(ofmsr)		TOC_ENTRY(ofmsr)
TOC_ENTRY(ofwstk)		TOC_ENTRY(ofwstk)
TOC_ENTRY(rtasmsr)		TOC_ENTRY(rtasmsr)
TOC_ENTRY(openfirmware_entry)		TOC_ENTRY(openfirmware_entry)
TOC_ENTRY(rtas_entry)		TOC_ENTRY(rtas_entry)
TOC_ENTRY(rtas_regsave)		TOC_ENTRY(rtas_regsave)

/*		/*
* Open Firmware Real-mode Entry Point. This is a huge pain.		* Open Firmware Real-mode Entry Point. This is a huge pain.
*/		*/

ASENTRY_NOPROF(ofwcall)		ASENTRY_NOPROF(ofwcall)
mflr %r0		mflr %r8
std %r0,16(%r1)		std %r8,16(%r1)
stdu %r1,-208(%r1)		stdu %r1,-208(%r1)

/*		/*
* We need to save the following, because OF's register save/		* We need to save the following, because OF's register save/
* restore code assumes that the contents of registers are		* restore code assumes that the contents of registers are
* at most 32 bits wide: lr, cr, r2, r13-r31, the old MSR. These		* at most 32 bits wide: lr, cr, r2, r13-r31, the old MSR. These
* get placed in that order in the stack.		* get placed in that order in the stack.
*/		*/
Show All 24 Lines	ASENTRY_NOPROF(ofwcall)
mfmsr %r6		mfmsr %r6

/* read client interface handler */		/* read client interface handler */
ld %r4,TOC_REF(openfirmware_entry)(%r2)		ld %r4,TOC_REF(openfirmware_entry)(%r2)
ld %r4,0(%r4)		ld %r4,0(%r4)

/* Get OF stack pointer */		/* Get OF stack pointer */
ld %r7,TOC_REF(ofwstk)(%r2)		ld %r7,TOC_REF(ofwstk)(%r2)
addi %r7,%r7,OFWSTKSZ-32		addi %r7,%r7,OFWSTKSZ-40

/*		/*
* Set the MSR to the OF value. This has the side effect of disabling		* Set the MSR to the OF value. This has the side effect of disabling
* exceptions, which is important for the next few steps.		* exceptions, which is important for the next few steps.
*/		*/

ld %r5,TOC_REF(ofmsr)(%r2)		ld %r5,TOC_REF(ofmsr)(%r2)
ld %r5,0(%r5)		ld %r5,0(%r5)
mtmsrd %r5		mtmsrd %r5
isync		isync

/*		/*
* Set up OF stack. This needs to be accessible in real mode and		* Set up OF stack. This needs to be accessible in real mode and
* use the 32-bit ABI stack frame format. The pointer to the current		* use the 32-bit ABI stack frame format. The pointer to the current
* kernel stack is placed at the very top of the stack along with		* kernel stack is placed at the very top of the stack along with
* the old MSR so we can get them back later.		* the old MSR so we can get them back later.
*/		*/
mr %r5,%r1		mr %r5,%r1
mr %r1,%r7		mr %r1,%r7
std %r5,8(%r1) /* Save real stack pointer */		std %r5,8(%r1) /* Save real stack pointer */
std %r2,16(%r1) /* Save old TOC */		std %r2,16(%r1) /* Save old TOC */
std %r6,24(%r1) /* Save old MSR */		std %r6,24(%r1) /* Save old MSR */
		std %r8,32(%r1) /* Save high 32-bits of the kernel's PC */

li %r5,0		li %r5,0
stw %r5,4(%r1)		stw %r5,4(%r1)
stw %r5,0(%r1)		stw %r5,0(%r1)

/* Finally, branch to OF */		/* Finally, branch to OF */
mtctr %r4		mtctr %r4
bctrl		bctrl

/* Reload stack pointer and MSR from the OFW stack */		/* Reload stack pointer, MSR, and reference PC from the OFW stack */
		ld %r7,32(%r1)
ld %r6,24(%r1)		ld %r6,24(%r1)
ld %r2,16(%r1)		ld %r2,16(%r1)
ld %r1,8(%r1)		ld %r1,8(%r1)

/* Now set the real MSR */		/* Get back to the MSR/PC we want, using the cached high bits of PC */
mtmsrd %r6		mtsrr1 %r6
isync		clrrdi %r7,%r7,32
		bl 1f
		1: mflr %r8
		or %r8,%r8,%r7
		addi %r8,%r8,2f-1b
		mtsrr0 %r8
		rfid /* Turn on MMU, exceptions, and 64-bit mode */

		2:
/* Sign-extend the return value from OF */		/* Sign-extend the return value from OF */
extsw %r3,%r3		extsw %r3,%r3

/* Restore all the non-volatile registers */		/* Restore all the non-volatile registers */
ld %r5,48(%r1)		ld %r5,48(%r1)
mtcr %r5		mtcr %r5
ld %r13,56(%r1)		ld %r13,56(%r1)
ld %r14,64(%r1)		ld %r14,64(%r1)
Show All 24 Lines
/*		/*
* RTAS 32-bit Entry Point. Similar to the OF one, but simpler (no separate		* RTAS 32-bit Entry Point. Similar to the OF one, but simpler (no separate
* stack)		* stack)
*		*
* C prototype: int rtascall(void callbuffer, void rtas_privdat);		* C prototype: int rtascall(void callbuffer, void rtas_privdat);
*/		*/

ASENTRY_NOPROF(rtascall)		ASENTRY_NOPROF(rtascall)
mflr %r0		mflr %r9
std %r0,16(%r1)		std %r9,16(%r1)
stdu %r1,-208(%r1)		stdu %r1,-208(%r1)

/*		/*
* We need to save the following, because RTAS's register save/		* We need to save the following, because RTAS's register save/
* restore code assumes that the contents of registers are		* restore code assumes that the contents of registers are
* at most 32 bits wide: lr, cr, r2, r13-r31, the old MSR. These		* at most 32 bits wide: lr, cr, r2, r13-r31, the old MSR. These
* get placed in that order in the stack.		* get placed in that order in the stack.
*/		*/
▲ Show 20 Lines • Show All 44 Lines • ▼ Show 20 Lines	ASENTRY_NOPROF(rtascall)
* Put this in r1, since RTAS is obliged to save it. Kernel globals		* Put this in r1, since RTAS is obliged to save it. Kernel globals
* are below 4 GB, so this is safe.		* are below 4 GB, so this is safe.
*/		*/
mr %r7,%r1		mr %r7,%r1
mr %r1,%r8		mr %r1,%r8
std %r7,0(%r1) /* Save 64-bit stack pointer */		std %r7,0(%r1) /* Save 64-bit stack pointer */
std %r2,8(%r1) /* Save TOC */		std %r2,8(%r1) /* Save TOC */
std %r6,16(%r1) /* Save MSR */		std %r6,16(%r1) /* Save MSR */
		std %r9,24(%r1) /* Save reference PC for high 32 bits */

/* Finally, branch to RTAS */		/* Finally, branch to RTAS */
mtctr %r5		mtctr %r5
bctrl		bctrl

/*		/*
* Reload stack pointer and MSR from the reg save area in r1. We are		* Reload stack pointer, MSR, reg PC from the reg save area in r1. We
* running in 32-bit mode at this point, so it doesn't matter if r1		* are running in 32-bit mode at this point, so it doesn't matter if r1
* has become sign-extended.		* has become sign-extended.
*/		*/
		ld %r7,24(%r1)
ld %r6,16(%r1)		ld %r6,16(%r1)
ld %r2,8(%r1)		ld %r2,8(%r1)
ld %r1,0(%r1)		ld %r1,0(%r1)

/* Now set the real MSR */		/*
mtmsrd %r6		* Get back to the right PC. We need to atomically re-enable
isync		* exceptions, 64-bit mode, and the MMU. One thing that has likely
		* happened is that, if we were running in the high-memory direct
		* map, we no longer are as a result of LR truncation in RTAS.
		* Fix this by copying the high-order bits of the LR at function
		* entry onto the current PC and then jumping there while flipping
		* all the MSR bits.
		*/
		mtsrr1 %r6
		clrrdi %r7,%r7,32
		bl 1f
		1: mflr %r8
		or %r8,%r8,%r7
		addi %r8,%r8,2f-1b
		mtsrr0 %r8
		rfid /* Turn on MMU, exceptions, and 64-bit mode */

		2:
/* Sign-extend the return value from RTAS */		/* Sign-extend the return value from RTAS */
extsw %r3,%r3		extsw %r3,%r3

/* Restore all the non-volatile registers */		/* Restore all the non-volatile registers */
ld %r5,48(%r1)		ld %r5,48(%r1)
mtcr %r5		mtcr %r5
ld %r13,56(%r1)		ld %r13,56(%r1)
ld %r14,64(%r1)		ld %r14,64(%r1)
Show All 24 Lines