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linux/arch/alpha/kernel/sys_cabriolet.c

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Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 00:20:36 +02:00
/*
* linux/arch/alpha/kernel/sys_cabriolet.c
*
* Copyright (C) 1995 David A Rusling
* Copyright (C) 1996 Jay A Estabrook
* Copyright (C) 1998, 1999, 2000 Richard Henderson
*
* Code supporting the Cabriolet (AlphaPC64), EB66+, and EB164,
* PC164 and LX164.
*/
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/sched.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/bitops.h>
#include <asm/ptrace.h>
#include <asm/system.h>
#include <asm/dma.h>
#include <asm/irq.h>
#include <asm/mmu_context.h>
#include <asm/io.h>
#include <asm/pgtable.h>
#include <asm/core_apecs.h>
#include <asm/core_cia.h>
#include <asm/core_lca.h>
#include <asm/tlbflush.h>
#include "proto.h"
#include "irq_impl.h"
#include "pci_impl.h"
#include "machvec_impl.h"
/* Note mask bit is true for DISABLED irqs. */
static unsigned long cached_irq_mask = ~0UL;
static inline void
cabriolet_update_irq_hw(unsigned int irq, unsigned long mask)
{
int ofs = (irq - 16) / 8;
outb(mask >> (16 + ofs * 8), 0x804 + ofs);
}
static inline void
cabriolet_enable_irq(unsigned int irq)
{
cabriolet_update_irq_hw(irq, cached_irq_mask &= ~(1UL << irq));
}
static void
cabriolet_disable_irq(unsigned int irq)
{
cabriolet_update_irq_hw(irq, cached_irq_mask |= 1UL << irq);
}
static unsigned int
cabriolet_startup_irq(unsigned int irq)
{
cabriolet_enable_irq(irq);
return 0; /* never anything pending */
}
static void
cabriolet_end_irq(unsigned int irq)
{
if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
cabriolet_enable_irq(irq);
}
static struct hw_interrupt_type cabriolet_irq_type = {
.typename = "CABRIOLET",
.startup = cabriolet_startup_irq,
.shutdown = cabriolet_disable_irq,
.enable = cabriolet_enable_irq,
.disable = cabriolet_disable_irq,
.ack = cabriolet_disable_irq,
.end = cabriolet_end_irq,
};
static void
[PATCH] alpha pt_regs cleanups: device_interrupt callers of ->device_interrupt() do set_irq_regs() now; pt_regs argument removed, remaining uses of regs in instances of ->device_interrupt() are switched to get_irq_regs() and will be gone in the next patch. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-08 15:36:08 +02:00
cabriolet_device_interrupt(unsigned long v)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 00:20:36 +02:00
{
unsigned long pld;
unsigned int i;
/* Read the interrupt summary registers */
pld = inb(0x804) | (inb(0x805) << 8) | (inb(0x806) << 16);
/*
* Now for every possible bit set, work through them and call
* the appropriate interrupt handler.
*/
while (pld) {
i = ffz(~pld);
pld &= pld - 1; /* clear least bit set */
if (i == 4) {
[PATCH] alpha pt_regs cleanups: device_interrupt callers of ->device_interrupt() do set_irq_regs() now; pt_regs argument removed, remaining uses of regs in instances of ->device_interrupt() are switched to get_irq_regs() and will be gone in the next patch. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-08 15:36:08 +02:00
isa_device_interrupt(v);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 00:20:36 +02:00
} else {
[PATCH] alpha pt_regs cleanups: handle_irq() isa_no_iack_sc_device_interrupt() always gets get_irq_regs() as argument; kill that argument. All but two callers of handle_irq() pass get_irq_regs() as argument; convert the remaining two, kill set_irq_regs() inside handle_irq(). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-08 15:37:32 +02:00
handle_irq(16 + i);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 00:20:36 +02:00
}
}
}
static void __init
[PATCH] alpha pt_regs cleanups: device_interrupt callers of ->device_interrupt() do set_irq_regs() now; pt_regs argument removed, remaining uses of regs in instances of ->device_interrupt() are switched to get_irq_regs() and will be gone in the next patch. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-08 15:36:08 +02:00
common_init_irq(void (*srm_dev_int)(unsigned long v))
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 00:20:36 +02:00
{
init_i8259a_irqs();
if (alpha_using_srm) {
alpha_mv.device_interrupt = srm_dev_int;
init_srm_irqs(35, 0);
}
else {
long i;
outb(0xff, 0x804);
outb(0xff, 0x805);
outb(0xff, 0x806);
for (i = 16; i < 35; ++i) {
irq_desc[i].status = IRQ_DISABLED | IRQ_LEVEL;
[PATCH] genirq: rename desc->handler to desc->chip This patch-queue improves the generic IRQ layer to be truly generic, by adding various abstractions and features to it, without impacting existing functionality. While the queue can be best described as "fix and improve everything in the generic IRQ layer that we could think of", and thus it consists of many smaller features and lots of cleanups, the one feature that stands out most is the new 'irq chip' abstraction. The irq-chip abstraction is about describing and coding and IRQ controller driver by mapping its raw hardware capabilities [and quirks, if needed] in a straightforward way, without having to think about "IRQ flow" (level/edge/etc.) type of details. This stands in contrast with the current 'irq-type' model of genirq architectures, which 'mixes' raw hardware capabilities with 'flow' details. The patchset supports both types of irq controller designs at once, and converts i386 and x86_64 to the new irq-chip design. As a bonus side-effect of the irq-chip approach, chained interrupt controllers (master/slave PIC constructs, etc.) are now supported by design as well. The end result of this patchset intends to be simpler architecture-level code and more consolidation between architectures. We reused many bits of code and many concepts from Russell King's ARM IRQ layer, the merging of which was one of the motivations for this patchset. This patch: rename desc->handler to desc->chip. Originally i did not want to do this, because it's a big patch. But having both "desc->handler", "desc->handle_irq" and "action->handler" caused a large degree of confusion and made the code appear alot less clean than it truly is. I have also attempted a dual approach as well by introducing a desc->chip alias - but that just wasnt robust enough and broke frequently. So lets get over with this quickly. The conversion was done automatically via scripts and converts all the code in the kernel. This renaming patch is the first one amongst the patches, so that the remaining patches can stay flexible and can be merged and split up without having some big monolithic patch act as a merge barrier. [akpm@osdl.org: build fix] [akpm@osdl.org: another build fix] Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 11:24:36 +02:00
irq_desc[i].chip = &cabriolet_irq_type;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 00:20:36 +02:00
}
}
common_init_isa_dma();
setup_irq(16+4, &isa_cascade_irqaction);
}
#ifndef CONFIG_ALPHA_PC164
static void __init
cabriolet_init_irq(void)
{
common_init_irq(srm_device_interrupt);
}
#endif
#if defined(CONFIG_ALPHA_GENERIC) || defined(CONFIG_ALPHA_PC164)
/* In theory, the PC164 has the same interrupt hardware as the other
Cabriolet based systems. However, something got screwed up late
in the development cycle which broke the interrupt masking hardware.
Repeat, it is not possible to mask and ack interrupts. At all.
In an attempt to work around this, while processing interrupts,
we do not allow the IPL to drop below what it is currently. This
prevents the possibility of recursion.
??? Another option might be to force all PCI devices to use edge
triggered rather than level triggered interrupts. That might be
too invasive though. */
static void
[PATCH] alpha pt_regs cleanups: device_interrupt callers of ->device_interrupt() do set_irq_regs() now; pt_regs argument removed, remaining uses of regs in instances of ->device_interrupt() are switched to get_irq_regs() and will be gone in the next patch. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-08 15:36:08 +02:00
pc164_srm_device_interrupt(unsigned long v)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 00:20:36 +02:00
{
__min_ipl = getipl();
[PATCH] alpha pt_regs cleanups: device_interrupt callers of ->device_interrupt() do set_irq_regs() now; pt_regs argument removed, remaining uses of regs in instances of ->device_interrupt() are switched to get_irq_regs() and will be gone in the next patch. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-08 15:36:08 +02:00
srm_device_interrupt(v);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 00:20:36 +02:00
__min_ipl = 0;
}
static void
[PATCH] alpha pt_regs cleanups: device_interrupt callers of ->device_interrupt() do set_irq_regs() now; pt_regs argument removed, remaining uses of regs in instances of ->device_interrupt() are switched to get_irq_regs() and will be gone in the next patch. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-08 15:36:08 +02:00
pc164_device_interrupt(unsigned long v)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 00:20:36 +02:00
{
__min_ipl = getipl();
[PATCH] alpha pt_regs cleanups: device_interrupt callers of ->device_interrupt() do set_irq_regs() now; pt_regs argument removed, remaining uses of regs in instances of ->device_interrupt() are switched to get_irq_regs() and will be gone in the next patch. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-08 15:36:08 +02:00
cabriolet_device_interrupt(v);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 00:20:36 +02:00
__min_ipl = 0;
}
static void __init
pc164_init_irq(void)
{
common_init_irq(pc164_srm_device_interrupt);
}
#endif
/*
* The EB66+ is very similar to the EB66 except that it does not have
* the on-board NCR and Tulip chips. In the code below, I have used
* slot number to refer to the id select line and *not* the slot
* number used in the EB66+ documentation. However, in the table,
* I've given the slot number, the id select line and the Jxx number
* that's printed on the board. The interrupt pins from the PCI slots
* are wired into 3 interrupt summary registers at 0x804, 0x805 and
* 0x806 ISA.
*
* In the table, -1 means don't assign an IRQ number. This is usually
* because it is the Saturn IO (SIO) PCI/ISA Bridge Chip.
*/
static inline int __init
eb66p_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
{
static char irq_tab[5][5] __initdata = {
/*INT INTA INTB INTC INTD */
{16+0, 16+0, 16+5, 16+9, 16+13}, /* IdSel 6, slot 0, J25 */
{16+1, 16+1, 16+6, 16+10, 16+14}, /* IdSel 7, slot 1, J26 */
{ -1, -1, -1, -1, -1}, /* IdSel 8, SIO */
{16+2, 16+2, 16+7, 16+11, 16+15}, /* IdSel 9, slot 2, J27 */
{16+3, 16+3, 16+8, 16+12, 16+6} /* IdSel 10, slot 3, J28 */
};
const long min_idsel = 6, max_idsel = 10, irqs_per_slot = 5;
return COMMON_TABLE_LOOKUP;
}
/*
* The AlphaPC64 is very similar to the EB66+ except that its slots
* are numbered differently. In the code below, I have used slot
* number to refer to the id select line and *not* the slot number
* used in the AlphaPC64 documentation. However, in the table, I've
* given the slot number, the id select line and the Jxx number that's
* printed on the board. The interrupt pins from the PCI slots are
* wired into 3 interrupt summary registers at 0x804, 0x805 and 0x806
* ISA.
*
* In the table, -1 means don't assign an IRQ number. This is usually
* because it is the Saturn IO (SIO) PCI/ISA Bridge Chip.
*/
static inline int __init
cabriolet_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
{
static char irq_tab[5][5] __initdata = {
/*INT INTA INTB INTC INTD */
{ 16+2, 16+2, 16+7, 16+11, 16+15}, /* IdSel 5, slot 2, J21 */
{ 16+0, 16+0, 16+5, 16+9, 16+13}, /* IdSel 6, slot 0, J19 */
{ 16+1, 16+1, 16+6, 16+10, 16+14}, /* IdSel 7, slot 1, J20 */
{ -1, -1, -1, -1, -1}, /* IdSel 8, SIO */
{ 16+3, 16+3, 16+8, 16+12, 16+16} /* IdSel 9, slot 3, J22 */
};
const long min_idsel = 5, max_idsel = 9, irqs_per_slot = 5;
return COMMON_TABLE_LOOKUP;
}
static inline void __init
cabriolet_init_pci(void)
{
common_init_pci();
ns87312_enable_ide(0x398);
}
static inline void __init
cia_cab_init_pci(void)
{
cia_init_pci();
ns87312_enable_ide(0x398);
}
/*
* The PC164 and LX164 have 19 PCI interrupts, four from each of the four
* PCI slots, the SIO, PCI/IDE, and USB.
*
* Each of the interrupts can be individually masked. This is
* accomplished by setting the appropriate bit in the mask register.
* A bit is set by writing a "1" to the desired position in the mask
* register and cleared by writing a "0". There are 3 mask registers
* located at ISA address 804h, 805h and 806h.
*
* An I/O read at ISA address 804h, 805h, 806h will return the
* state of the 11 PCI interrupts and not the state of the MASKED
* interrupts.
*
* Note: A write to I/O 804h, 805h, and 806h the mask register will be
* updated.
*
*
* ISA DATA<7:0>
* ISA +--------------------------------------------------------------+
* ADDRESS | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
* +==============================================================+
* 0x804 | INTB0 | USB | IDE | SIO | INTA3 |INTA2 | INTA1 | INTA0 |
* +--------------------------------------------------------------+
* 0x805 | INTD0 | INTC3 | INTC2 | INTC1 | INTC0 |INTB3 | INTB2 | INTB1 |
* +--------------------------------------------------------------+
* 0x806 | Rsrv | Rsrv | Rsrv | Rsrv | Rsrv |INTD3 | INTD2 | INTD1 |
* +--------------------------------------------------------------+
* * Rsrv = reserved bits
* Note: The mask register is write-only.
*
* IdSel
* 5 32 bit PCI option slot 2
* 6 64 bit PCI option slot 0
* 7 64 bit PCI option slot 1
* 8 Saturn I/O
* 9 32 bit PCI option slot 3
* 10 USB
* 11 IDE
*
*/
static inline int __init
alphapc164_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
{
static char irq_tab[7][5] __initdata = {
/*INT INTA INTB INTC INTD */
{ 16+2, 16+2, 16+9, 16+13, 16+17}, /* IdSel 5, slot 2, J20 */
{ 16+0, 16+0, 16+7, 16+11, 16+15}, /* IdSel 6, slot 0, J29 */
{ 16+1, 16+1, 16+8, 16+12, 16+16}, /* IdSel 7, slot 1, J26 */
{ -1, -1, -1, -1, -1}, /* IdSel 8, SIO */
{ 16+3, 16+3, 16+10, 16+14, 16+18}, /* IdSel 9, slot 3, J19 */
{ 16+6, 16+6, 16+6, 16+6, 16+6}, /* IdSel 10, USB */
{ 16+5, 16+5, 16+5, 16+5, 16+5} /* IdSel 11, IDE */
};
const long min_idsel = 5, max_idsel = 11, irqs_per_slot = 5;
return COMMON_TABLE_LOOKUP;
}
static inline void __init
alphapc164_init_pci(void)
{
cia_init_pci();
SMC93x_Init();
}
/*
* The System Vector
*/
#if defined(CONFIG_ALPHA_GENERIC) || defined(CONFIG_ALPHA_CABRIOLET)
struct alpha_machine_vector cabriolet_mv __initmv = {
.vector_name = "Cabriolet",
DO_EV4_MMU,
DO_DEFAULT_RTC,
DO_APECS_IO,
.machine_check = apecs_machine_check,
.max_isa_dma_address = ALPHA_MAX_ISA_DMA_ADDRESS,
.min_io_address = DEFAULT_IO_BASE,
.min_mem_address = APECS_AND_LCA_DEFAULT_MEM_BASE,
.nr_irqs = 35,
.device_interrupt = cabriolet_device_interrupt,
.init_arch = apecs_init_arch,
.init_irq = cabriolet_init_irq,
.init_rtc = common_init_rtc,
.init_pci = cabriolet_init_pci,
.pci_map_irq = cabriolet_map_irq,
.pci_swizzle = common_swizzle,
};
#ifndef CONFIG_ALPHA_EB64P
ALIAS_MV(cabriolet)
#endif
#endif
#if defined(CONFIG_ALPHA_GENERIC) || defined(CONFIG_ALPHA_EB164)
struct alpha_machine_vector eb164_mv __initmv = {
.vector_name = "EB164",
DO_EV5_MMU,
DO_DEFAULT_RTC,
DO_CIA_IO,
.machine_check = cia_machine_check,
.max_isa_dma_address = ALPHA_MAX_ISA_DMA_ADDRESS,
.min_io_address = DEFAULT_IO_BASE,
.min_mem_address = CIA_DEFAULT_MEM_BASE,
.nr_irqs = 35,
.device_interrupt = cabriolet_device_interrupt,
.init_arch = cia_init_arch,
.init_irq = cabriolet_init_irq,
.init_rtc = common_init_rtc,
.init_pci = cia_cab_init_pci,
.kill_arch = cia_kill_arch,
.pci_map_irq = cabriolet_map_irq,
.pci_swizzle = common_swizzle,
};
ALIAS_MV(eb164)
#endif
#if defined(CONFIG_ALPHA_GENERIC) || defined(CONFIG_ALPHA_EB66P)
struct alpha_machine_vector eb66p_mv __initmv = {
.vector_name = "EB66+",
DO_EV4_MMU,
DO_DEFAULT_RTC,
DO_LCA_IO,
.machine_check = lca_machine_check,
.max_isa_dma_address = ALPHA_MAX_ISA_DMA_ADDRESS,
.min_io_address = DEFAULT_IO_BASE,
.min_mem_address = APECS_AND_LCA_DEFAULT_MEM_BASE,
.nr_irqs = 35,
.device_interrupt = cabriolet_device_interrupt,
.init_arch = lca_init_arch,
.init_irq = cabriolet_init_irq,
.init_rtc = common_init_rtc,
.init_pci = cabriolet_init_pci,
.pci_map_irq = eb66p_map_irq,
.pci_swizzle = common_swizzle,
};
ALIAS_MV(eb66p)
#endif
#if defined(CONFIG_ALPHA_GENERIC) || defined(CONFIG_ALPHA_LX164)
struct alpha_machine_vector lx164_mv __initmv = {
.vector_name = "LX164",
DO_EV5_MMU,
DO_DEFAULT_RTC,
DO_PYXIS_IO,
.machine_check = cia_machine_check,
.max_isa_dma_address = ALPHA_MAX_ISA_DMA_ADDRESS,
.min_io_address = DEFAULT_IO_BASE,
.min_mem_address = DEFAULT_MEM_BASE,
.pci_dac_offset = PYXIS_DAC_OFFSET,
.nr_irqs = 35,
.device_interrupt = cabriolet_device_interrupt,
.init_arch = pyxis_init_arch,
.init_irq = cabriolet_init_irq,
.init_rtc = common_init_rtc,
.init_pci = alphapc164_init_pci,
.kill_arch = cia_kill_arch,
.pci_map_irq = alphapc164_map_irq,
.pci_swizzle = common_swizzle,
};
ALIAS_MV(lx164)
#endif
#if defined(CONFIG_ALPHA_GENERIC) || defined(CONFIG_ALPHA_PC164)
struct alpha_machine_vector pc164_mv __initmv = {
.vector_name = "PC164",
DO_EV5_MMU,
DO_DEFAULT_RTC,
DO_CIA_IO,
.machine_check = cia_machine_check,
.max_isa_dma_address = ALPHA_MAX_ISA_DMA_ADDRESS,
.min_io_address = DEFAULT_IO_BASE,
.min_mem_address = CIA_DEFAULT_MEM_BASE,
.nr_irqs = 35,
.device_interrupt = pc164_device_interrupt,
.init_arch = cia_init_arch,
.init_irq = pc164_init_irq,
.init_rtc = common_init_rtc,
.init_pci = alphapc164_init_pci,
.kill_arch = cia_kill_arch,
.pci_map_irq = alphapc164_map_irq,
.pci_swizzle = common_swizzle,
};
ALIAS_MV(pc164)
#endif