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Diffstat (limited to 'arch/parisc/kernel/real2.S')
| -rw-r--r-- | arch/parisc/kernel/real2.S | 292 |
1 files changed, 292 insertions, 0 deletions
diff --git a/arch/parisc/kernel/real2.S b/arch/parisc/kernel/real2.S new file mode 100644 index 0000000000..509d18b8e0 --- /dev/null +++ b/arch/parisc/kernel/real2.S @@ -0,0 +1,292 @@ +/* + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (C) 2000 Hewlett Packard (Paul Bame bame@puffin.external.hp.com) + * + */ + +#include <asm/pdc.h> +#include <asm/psw.h> +#include <asm/assembly.h> +#include <asm/asm-offsets.h> + +#include <linux/linkage.h> + + .export real_stack + .export real64_stack + __PAGE_ALIGNED_BSS +real_stack: +real64_stack: + .block 8192 + +#define N_SAVED_REGS 9 + .section .bss +save_cr_space: + .block REG_SZ * N_SAVED_REGS +save_cr_end: + + +/************************ 32-bit real-mode calls ***********************/ +/* This can be called in both narrow and wide kernels */ + + .text + + /* unsigned long real32_call_asm(unsigned int *sp, + * unsigned int *arg0p, + * unsigned int iodc_fn) + * sp is value of stack pointer to adopt before calling PDC (virt) + * arg0p points to where saved arg values may be found + * iodc_fn is the IODC function to call + */ + +ENTRY_CFI(real32_call_asm) + STREG %rp, -RP_OFFSET(%sp) /* save RP */ +#ifdef CONFIG_64BIT + callee_save + ldo 2*REG_SZ(%sp), %sp /* room for a couple more saves */ + STREG %r27, -1*REG_SZ(%sp) + STREG %r29, -2*REG_SZ(%sp) +#endif + STREG %sp, -REG_SZ(%arg0) /* save SP on real-mode stack */ + copy %arg0, %sp /* adopt the real-mode SP */ + + /* save iodc_fn */ + copy %arg2, %r31 + + /* load up the arg registers from the saved arg area */ + /* 32-bit calling convention passes first 4 args in registers */ + ldw 0(%arg1), %arg0 /* note overwriting arg0 */ + ldw -8(%arg1), %arg2 + ldw -12(%arg1), %arg3 + ldw -4(%arg1), %arg1 /* obviously must do this one last! */ + + tophys_r1 %sp + + b,l rfi_virt2real,%r2 + nop + + b,l save_control_regs,%r2 /* modifies r1, r2, r28 */ + nop + +#ifdef CONFIG_64BIT + rsm PSW_SM_W, %r0 /* go narrow */ +#endif + + load32 PA(ric_ret), %r2 + bv 0(%r31) + nop +ric_ret: +#ifdef CONFIG_64BIT + ssm PSW_SM_W, %r0 /* go wide */ +#endif + /* restore CRs before going virtual in case we page fault */ + b,l restore_control_regs, %r2 /* modifies r1, r2, r26 */ + nop + + b,l rfi_real2virt,%r2 + nop + + tovirt_r1 %sp + LDREG -REG_SZ(%sp), %sp /* restore SP */ +#ifdef CONFIG_64BIT + LDREG -1*REG_SZ(%sp), %r27 + LDREG -2*REG_SZ(%sp), %r29 + ldo -2*REG_SZ(%sp), %sp + callee_rest +#endif + LDREG -RP_OFFSET(%sp), %rp /* restore RP */ + bv 0(%rp) + nop +ENDPROC_CFI(real32_call_asm) + + +# define PUSH_CR(r, where) mfctl r, %r1 ! STREG,ma %r1, REG_SZ(where) +# define POP_CR(r, where) LDREG,mb -REG_SZ(where), %r1 ! mtctl %r1, r + + .text +ENTRY_CFI(save_control_regs) + load32 PA(save_cr_space), %r28 + PUSH_CR(%cr24, %r28) + PUSH_CR(%cr25, %r28) + PUSH_CR(%cr26, %r28) + PUSH_CR(%cr27, %r28) + PUSH_CR(%cr28, %r28) + PUSH_CR(%cr29, %r28) + PUSH_CR(%cr30, %r28) + PUSH_CR(%cr31, %r28) + PUSH_CR(%cr15, %r28) + bv 0(%r2) + nop +ENDPROC_CFI(save_control_regs) + +ENTRY_CFI(restore_control_regs) + load32 PA(save_cr_end), %r26 + POP_CR(%cr15, %r26) + POP_CR(%cr31, %r26) + POP_CR(%cr30, %r26) + POP_CR(%cr29, %r26) + POP_CR(%cr28, %r26) + POP_CR(%cr27, %r26) + POP_CR(%cr26, %r26) + POP_CR(%cr25, %r26) + POP_CR(%cr24, %r26) + bv 0(%r2) + nop +ENDPROC_CFI(restore_control_regs) + +/* rfi_virt2real() and rfi_real2virt() could perhaps be adapted for + * more general-purpose use by the several places which need RFIs + */ + .text + .align 128 +ENTRY_CFI(rfi_virt2real) +#if !defined(BOOTLOADER) + /* switch to real mode... */ + rsm PSW_SM_I,%r0 + load32 PA(rfi_v2r_1), %r1 + nop + nop + nop + nop + nop + + rsm PSW_SM_Q,%r0 /* disable Q & I bits to load iia queue */ + mtctl %r0, %cr17 /* Clear IIASQ tail */ + mtctl %r0, %cr17 /* Clear IIASQ head */ + mtctl %r1, %cr18 /* IIAOQ head */ + ldo 4(%r1), %r1 + mtctl %r1, %cr18 /* IIAOQ tail */ + load32 REAL_MODE_PSW, %r1 + mtctl %r1, %cr22 + rfi + + nop + nop + nop + nop + nop + nop + nop + nop +rfi_v2r_1: + tophys_r1 %r2 +#endif /* defined(BOOTLOADER) */ + bv 0(%r2) + nop +ENDPROC_CFI(rfi_virt2real) + + .text + .align 128 +ENTRY_CFI(rfi_real2virt) +#if !defined(BOOTLOADER) + rsm PSW_SM_I,%r0 + load32 (rfi_r2v_1), %r1 + nop + nop + nop + nop + nop + + rsm PSW_SM_Q,%r0 /* disable Q bit to load iia queue */ + mtctl %r0, %cr17 /* Clear IIASQ tail */ + mtctl %r0, %cr17 /* Clear IIASQ head */ + mtctl %r1, %cr18 /* IIAOQ head */ + ldo 4(%r1), %r1 + mtctl %r1, %cr18 /* IIAOQ tail */ + load32 KERNEL_PSW, %r1 + mtctl %r1, %cr22 + rfi + + nop + nop + nop + nop + nop + nop + nop + nop +rfi_r2v_1: + tovirt_r1 %r2 +#endif /* defined(BOOTLOADER) */ + bv 0(%r2) + nop +ENDPROC_CFI(rfi_real2virt) + +#ifdef CONFIG_64BIT + +/************************ 64-bit real-mode calls ***********************/ +/* This is only usable in wide kernels right now and will probably stay so */ + .text + /* unsigned long real64_call_asm(unsigned long *sp, + * unsigned long *arg0p, + * unsigned long fn) + * sp is value of stack pointer to adopt before calling PDC (virt) + * arg0p points to where saved arg values may be found + * iodc_fn is the IODC function to call + */ +ENTRY_CFI(real64_call_asm) + std %rp, -0x10(%sp) /* save RP */ + std %sp, -8(%arg0) /* save SP on real-mode stack */ + copy %arg0, %sp /* adopt the real-mode SP */ + + /* save fn */ + copy %arg2, %r31 + + /* load up the arg registers from the saved arg area */ + /* 32-bit calling convention passes first 4 args in registers */ + ldd 0*REG_SZ(%arg1), %arg0 /* note overwriting arg0 */ + ldd 2*REG_SZ(%arg1), %arg2 + ldd 3*REG_SZ(%arg1), %arg3 + ldd 4*REG_SZ(%arg1), %r22 + ldd 5*REG_SZ(%arg1), %r21 + ldd 6*REG_SZ(%arg1), %r20 + ldd 7*REG_SZ(%arg1), %r19 + ldd 1*REG_SZ(%arg1), %arg1 /* do this one last! */ + + /* set up real-mode stack and real-mode ap */ + tophys_r1 %sp + ldo -16(%sp), %r29 /* Reference param save area */ + + b,l rfi_virt2real,%r2 + nop + + b,l save_control_regs,%r2 /* modifies r1, r2, r28 */ + nop + + load32 PA(r64_ret), %r2 + bv 0(%r31) + nop +r64_ret: + /* restore CRs before going virtual in case we page fault */ + b,l restore_control_regs, %r2 /* modifies r1, r2, r26 */ + nop + + b,l rfi_real2virt,%r2 + nop + + tovirt_r1 %sp + ldd -8(%sp), %sp /* restore SP */ + ldd -0x10(%sp), %rp /* restore RP */ + bv 0(%rp) + nop +ENDPROC_CFI(real64_call_asm) + +#endif + + .text + /* http://lists.parisc-linux.org/hypermail/parisc-linux/10916.html + ** GCC 3.3 and later has a new function in libgcc.a for + ** comparing function pointers. + */ +ENTRY_CFI(__canonicalize_funcptr_for_compare) +#ifdef CONFIG_64BIT + bve (%r2) +#else + bv %r0(%r2) +#endif + copy %r26,%r28 +ENDPROC_CFI(__canonicalize_funcptr_for_compare) + |