linux/arch/arm/mach-footbridge/common.c
Arnd Bergmann 90890f17cc ARM: footbridge: use GENERIC_IRQ_MULTI_HANDLER
Footbridge still uses the classic IRQ entry path in assembler,
but this is easily converted into an equivalent C version.

In this case, the correlation between IRQ numbers and bits in
the status register is non-obvious, and the priorities are
handled by manually checking each bit in a static order,
re-reading the status register after each handled event.

I moved the code into the new file and edited the syntax without
changing this sequence to keep the behavior as close as possible
to what it traditionally did.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2021-12-06 12:48:47 +01:00

352 lines
7.6 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* linux/arch/arm/mach-footbridge/common.c
*
* Copyright (C) 1998-2000 Russell King, Dave Gilbert.
*/
#include <linux/module.h>
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/ioport.h>
#include <linux/list.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/spinlock.h>
#include <video/vga.h>
#include <asm/page.h>
#include <asm/irq.h>
#include <asm/mach-types.h>
#include <asm/setup.h>
#include <asm/system_misc.h>
#include <asm/hardware/dec21285.h>
#include <asm/mach/irq.h>
#include <asm/mach/map.h>
#include <asm/mach/pci.h>
#include "common.h"
#include <mach/hardware.h>
#include <mach/irqs.h>
#include <asm/hardware/dec21285.h>
static int dc21285_get_irq(void)
{
void __iomem *irqstatus = (void __iomem *)CSR_IRQ_STATUS;
u32 mask = readl(irqstatus);
if (mask & IRQ_MASK_SDRAMPARITY)
return IRQ_SDRAMPARITY;
if (mask & IRQ_MASK_UART_RX)
return IRQ_CONRX;
if (mask & IRQ_MASK_DMA1)
return IRQ_DMA1;
if (mask & IRQ_MASK_DMA2)
return IRQ_DMA2;
if (mask & IRQ_MASK_IN0)
return IRQ_IN0;
if (mask & IRQ_MASK_IN1)
return IRQ_IN1;
if (mask & IRQ_MASK_IN2)
return IRQ_IN2;
if (mask & IRQ_MASK_IN3)
return IRQ_IN3;
if (mask & IRQ_MASK_PCI)
return IRQ_PCI;
if (mask & IRQ_MASK_DOORBELLHOST)
return IRQ_DOORBELLHOST;
if (mask & IRQ_MASK_I2OINPOST)
return IRQ_I2OINPOST;
if (mask & IRQ_MASK_TIMER1)
return IRQ_TIMER1;
if (mask & IRQ_MASK_TIMER2)
return IRQ_TIMER2;
if (mask & IRQ_MASK_TIMER3)
return IRQ_TIMER3;
if (mask & IRQ_MASK_UART_TX)
return IRQ_CONTX;
if (mask & IRQ_MASK_PCI_ABORT)
return IRQ_PCI_ABORT;
if (mask & IRQ_MASK_PCI_SERR)
return IRQ_PCI_SERR;
if (mask & IRQ_MASK_DISCARD_TIMER)
return IRQ_DISCARD_TIMER;
if (mask & IRQ_MASK_PCI_DPERR)
return IRQ_PCI_DPERR;
if (mask & IRQ_MASK_PCI_PERR)
return IRQ_PCI_PERR;
return 0;
}
static void dc21285_handle_irq(struct pt_regs *regs)
{
int irq;
do {
irq = dc21285_get_irq();
if (!irq)
break;
generic_handle_irq(irq);
} while (1);
}
unsigned int mem_fclk_21285 = 50000000;
EXPORT_SYMBOL(mem_fclk_21285);
static int __init early_fclk(char *arg)
{
mem_fclk_21285 = simple_strtoul(arg, NULL, 0);
return 0;
}
early_param("mem_fclk_21285", early_fclk);
static int __init parse_tag_memclk(const struct tag *tag)
{
mem_fclk_21285 = tag->u.memclk.fmemclk;
return 0;
}
__tagtable(ATAG_MEMCLK, parse_tag_memclk);
/*
* Footbridge IRQ translation table
* Converts from our IRQ numbers into FootBridge masks
*/
static const int fb_irq_mask[] = {
IRQ_MASK_UART_RX, /* 0 */
IRQ_MASK_UART_TX, /* 1 */
IRQ_MASK_TIMER1, /* 2 */
IRQ_MASK_TIMER2, /* 3 */
IRQ_MASK_TIMER3, /* 4 */
IRQ_MASK_IN0, /* 5 */
IRQ_MASK_IN1, /* 6 */
IRQ_MASK_IN2, /* 7 */
IRQ_MASK_IN3, /* 8 */
IRQ_MASK_DOORBELLHOST, /* 9 */
IRQ_MASK_DMA1, /* 10 */
IRQ_MASK_DMA2, /* 11 */
IRQ_MASK_PCI, /* 12 */
IRQ_MASK_SDRAMPARITY, /* 13 */
IRQ_MASK_I2OINPOST, /* 14 */
IRQ_MASK_PCI_ABORT, /* 15 */
IRQ_MASK_PCI_SERR, /* 16 */
IRQ_MASK_DISCARD_TIMER, /* 17 */
IRQ_MASK_PCI_DPERR, /* 18 */
IRQ_MASK_PCI_PERR, /* 19 */
};
static void fb_mask_irq(struct irq_data *d)
{
*CSR_IRQ_DISABLE = fb_irq_mask[_DC21285_INR(d->irq)];
}
static void fb_unmask_irq(struct irq_data *d)
{
*CSR_IRQ_ENABLE = fb_irq_mask[_DC21285_INR(d->irq)];
}
static struct irq_chip fb_chip = {
.irq_ack = fb_mask_irq,
.irq_mask = fb_mask_irq,
.irq_unmask = fb_unmask_irq,
};
static void __init __fb_init_irq(void)
{
unsigned int irq;
/*
* setup DC21285 IRQs
*/
*CSR_IRQ_DISABLE = -1;
*CSR_FIQ_DISABLE = -1;
for (irq = _DC21285_IRQ(0); irq < _DC21285_IRQ(20); irq++) {
irq_set_chip_and_handler(irq, &fb_chip, handle_level_irq);
irq_clear_status_flags(irq, IRQ_NOREQUEST | IRQ_NOPROBE);
}
}
void __init footbridge_init_irq(void)
{
set_handle_irq(dc21285_handle_irq);
__fb_init_irq();
if (!footbridge_cfn_mode())
return;
if (machine_is_ebsa285())
/* The following is dependent on which slot
* you plug the Southbridge card into. We
* currently assume that you plug it into
* the right-hand most slot.
*/
isa_init_irq(IRQ_PCI);
if (machine_is_cats())
isa_init_irq(IRQ_IN2);
if (machine_is_netwinder())
isa_init_irq(IRQ_IN3);
}
/*
* Common mapping for all systems. Note that the outbound write flush is
* commented out since there is a "No Fix" problem with it. Not mapping
* it means that we have extra bullet protection on our feet.
*/
static struct map_desc fb_common_io_desc[] __initdata = {
{
.virtual = ARMCSR_BASE,
.pfn = __phys_to_pfn(DC21285_ARMCSR_BASE),
.length = ARMCSR_SIZE,
.type = MT_DEVICE,
}
};
/*
* The mapping when the footbridge is in host mode. We don't map any of
* this when we are in add-in mode.
*/
static struct map_desc ebsa285_host_io_desc[] __initdata = {
#if defined(CONFIG_ARCH_FOOTBRIDGE) && defined(CONFIG_FOOTBRIDGE_HOST)
{
.virtual = PCIMEM_BASE,
.pfn = __phys_to_pfn(DC21285_PCI_MEM),
.length = PCIMEM_SIZE,
.type = MT_DEVICE,
}, {
.virtual = PCICFG0_BASE,
.pfn = __phys_to_pfn(DC21285_PCI_TYPE_0_CONFIG),
.length = PCICFG0_SIZE,
.type = MT_DEVICE,
}, {
.virtual = PCICFG1_BASE,
.pfn = __phys_to_pfn(DC21285_PCI_TYPE_1_CONFIG),
.length = PCICFG1_SIZE,
.type = MT_DEVICE,
}, {
.virtual = PCIIACK_BASE,
.pfn = __phys_to_pfn(DC21285_PCI_IACK),
.length = PCIIACK_SIZE,
.type = MT_DEVICE,
},
#endif
};
void __init footbridge_map_io(void)
{
/*
* Set up the common mapping first; we need this to
* determine whether we're in host mode or not.
*/
iotable_init(fb_common_io_desc, ARRAY_SIZE(fb_common_io_desc));
/*
* Now, work out what we've got to map in addition on this
* platform.
*/
if (footbridge_cfn_mode()) {
iotable_init(ebsa285_host_io_desc, ARRAY_SIZE(ebsa285_host_io_desc));
pci_map_io_early(__phys_to_pfn(DC21285_PCI_IO));
}
vga_base = PCIMEM_BASE;
}
void footbridge_restart(enum reboot_mode mode, const char *cmd)
{
if (mode == REBOOT_SOFT) {
/* Jump into the ROM */
soft_restart(0x41000000);
} else {
/*
* Force the watchdog to do a CPU reset.
*
* After making sure that the watchdog is disabled
* (so we can change the timer registers) we first
* enable the timer to autoreload itself. Next, the
* timer interval is set really short and any
* current interrupt request is cleared (so we can
* see an edge transition). Finally, TIMER4 is
* enabled as the watchdog.
*/
*CSR_SA110_CNTL &= ~(1 << 13);
*CSR_TIMER4_CNTL = TIMER_CNTL_ENABLE |
TIMER_CNTL_AUTORELOAD |
TIMER_CNTL_DIV16;
*CSR_TIMER4_LOAD = 0x2;
*CSR_TIMER4_CLR = 0;
*CSR_SA110_CNTL |= (1 << 13);
}
}
#ifdef CONFIG_FOOTBRIDGE_ADDIN
static inline unsigned long fb_bus_sdram_offset(void)
{
return *CSR_PCISDRAMBASE & 0xfffffff0;
}
/*
* These two functions convert virtual addresses to PCI addresses and PCI
* addresses to virtual addresses. Note that it is only legal to use these
* on memory obtained via get_zeroed_page or kmalloc.
*/
unsigned long __virt_to_bus(unsigned long res)
{
WARN_ON(res < PAGE_OFFSET || res >= (unsigned long)high_memory);
return res + (fb_bus_sdram_offset() - PAGE_OFFSET);
}
EXPORT_SYMBOL(__virt_to_bus);
unsigned long __bus_to_virt(unsigned long res)
{
res = res - (fb_bus_sdram_offset() - PAGE_OFFSET);
WARN_ON(res < PAGE_OFFSET || res >= (unsigned long)high_memory);
return res;
}
EXPORT_SYMBOL(__bus_to_virt);
unsigned long __pfn_to_bus(unsigned long pfn)
{
return __pfn_to_phys(pfn) + (fb_bus_sdram_offset() - PHYS_OFFSET);
}
EXPORT_SYMBOL(__pfn_to_bus);
unsigned long __bus_to_pfn(unsigned long bus)
{
return __phys_to_pfn(bus - (fb_bus_sdram_offset() - PHYS_OFFSET));
}
EXPORT_SYMBOL(__bus_to_pfn);
#endif