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Release 4.14 arch/mips/sni/rm200.c

Directory: arch/mips/sni
/*
 * RM200 specific code
 *
 * 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) 2006,2007 Thomas Bogendoerfer (tsbogend@alpha.franken.de)
 *
 * i8259 parts ripped out of arch/mips/kernel/i8259.c
 */

#include <linux/delay.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/platform_device.h>
#include <linux/serial_8250.h>
#include <linux/io.h>

#include <asm/sni.h>
#include <asm/time.h>
#include <asm/irq_cpu.h>


#define RM200_I8259A_IRQ_BASE 32


#define MEMPORT(_base,_irq)				\
	{                                               \
                .mapbase        = _base,                \
                .irq            = _irq,                 \
                .uartclk        = 1843200,              \
                .iotype         = UPIO_MEM,             \
                .flags          = UPF_BOOT_AUTOCONF|UPF_IOREMAP, \
        }


static struct plat_serial8250_port rm200_data[] = {
	MEMPORT(0x160003f8, RM200_I8259A_IRQ_BASE + 4),
	MEMPORT(0x160002f8, RM200_I8259A_IRQ_BASE + 3),
	{ },
};


static struct platform_device rm200_serial8250_device = {
	.name			= "serial8250",
	.id			= PLAT8250_DEV_PLATFORM,
	.dev			= {
		.platform_data	= rm200_data,
        },
};


static struct resource rm200_ds1216_rsrc[] = {
	{
		.start = 0x1cd41ffc,
		.end   = 0x1cd41fff,
		.flags = IORESOURCE_MEM
	}
};


static struct platform_device rm200_ds1216_device = {
	.name		= "rtc-ds1216",
	.num_resources	= ARRAY_SIZE(rm200_ds1216_rsrc),
	.resource	= rm200_ds1216_rsrc
};


static struct resource snirm_82596_rm200_rsrc[] = {
	{
		.start = 0x18000000,
		.end   = 0x180fffff,
		.flags = IORESOURCE_MEM
	},
	{
		.start = 0x1b000000,
		.end   = 0x1b000004,
		.flags = IORESOURCE_MEM
	},
	{
		.start = 0x1ff00000,
		.end   = 0x1ff00020,
		.flags = IORESOURCE_MEM
	},
	{
		.start = 27,
		.end   = 27,
		.flags = IORESOURCE_IRQ
	},
	{
		.flags = 0x00
	}
};


static struct platform_device snirm_82596_rm200_pdev = {
	.name		= "snirm_82596",
	.num_resources	= ARRAY_SIZE(snirm_82596_rm200_rsrc),
	.resource	= snirm_82596_rm200_rsrc
};


static struct resource snirm_53c710_rm200_rsrc[] = {
	{
		.start = 0x19000000,
		.end   = 0x190fffff,
		.flags = IORESOURCE_MEM
	},
	{
		.start = 26,
		.end   = 26,
		.flags = IORESOURCE_IRQ
	}
};


static struct platform_device snirm_53c710_rm200_pdev = {
	.name		= "snirm_53c710",
	.num_resources	= ARRAY_SIZE(snirm_53c710_rm200_rsrc),
	.resource	= snirm_53c710_rm200_rsrc
};


static int __init snirm_setup_devinit(void) { if (sni_brd_type == SNI_BRD_RM200) { platform_device_register(&rm200_serial8250_device); platform_device_register(&rm200_ds1216_device); platform_device_register(&snirm_82596_rm200_pdev); platform_device_register(&snirm_53c710_rm200_pdev); sni_eisa_root_init(); } return 0; }

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Thomas Bogendoerfer47100.00%3100.00%
Total47100.00%3100.00%

device_initcall(snirm_setup_devinit); /* * RM200 has an ISA and an EISA bus. The iSA bus is only used * for onboard devices and also has twi i8259 PICs. Since these * PICs are no accessible via inb/outb the following code uses * readb/writeb to access them */ static DEFINE_RAW_SPINLOCK(sni_rm200_i8259A_lock); #define PIC_CMD 0x00 #define PIC_IMR 0x01 #define PIC_ISR PIC_CMD #define PIC_POLL PIC_ISR #define PIC_OCW3 PIC_ISR /* i8259A PIC related value */ #define PIC_CASCADE_IR 2 #define MASTER_ICW4_DEFAULT 0x01 #define SLAVE_ICW4_DEFAULT 0x01 /* * This contains the irq mask for both 8259A irq controllers, */ static unsigned int rm200_cached_irq_mask = 0xffff; static __iomem u8 *rm200_pic_master; static __iomem u8 *rm200_pic_slave; #define cached_master_mask (rm200_cached_irq_mask) #define cached_slave_mask (rm200_cached_irq_mask >> 8)
static void sni_rm200_disable_8259A_irq(struct irq_data *d) { unsigned int mask, irq = d->irq - RM200_I8259A_IRQ_BASE; unsigned long flags; mask = 1 << irq; raw_spin_lock_irqsave(&sni_rm200_i8259A_lock, flags); rm200_cached_irq_mask |= mask; if (irq & 8) writeb(cached_slave_mask, rm200_pic_slave + PIC_IMR); else writeb(cached_master_mask, rm200_pic_master + PIC_IMR); raw_spin_unlock_irqrestore(&sni_rm200_i8259A_lock, flags); }

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Thomas Bogendoerfer6482.05%250.00%
Thomas Gleixner1215.38%125.00%
Ralf Bächle22.56%125.00%
Total78100.00%4100.00%


static void sni_rm200_enable_8259A_irq(struct irq_data *d) { unsigned int mask, irq = d->irq - RM200_I8259A_IRQ_BASE; unsigned long flags; mask = ~(1 << irq); raw_spin_lock_irqsave(&sni_rm200_i8259A_lock, flags); rm200_cached_irq_mask &= mask; if (irq & 8) writeb(cached_slave_mask, rm200_pic_slave + PIC_IMR); else writeb(cached_master_mask, rm200_pic_master + PIC_IMR); raw_spin_unlock_irqrestore(&sni_rm200_i8259A_lock, flags); }

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PersonTokensPropCommitsCommitProp
Thomas Bogendoerfer6782.72%250.00%
Thomas Gleixner1214.81%125.00%
Ralf Bächle22.47%125.00%
Total81100.00%4100.00%


static inline int sni_rm200_i8259A_irq_real(unsigned int irq) { int value; int irqmask = 1 << irq; if (irq < 8) { writeb(0x0B, rm200_pic_master + PIC_CMD); value = readb(rm200_pic_master + PIC_CMD) & irqmask; writeb(0x0A, rm200_pic_master + PIC_CMD); return value; } writeb(0x0B, rm200_pic_slave + PIC_CMD); /* ISR register */ value = readb(rm200_pic_slave + PIC_CMD) & (irqmask >> 8); writeb(0x0A, rm200_pic_slave + PIC_CMD); return value; }

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Thomas Bogendoerfer98100.00%2100.00%
Total98100.00%2100.00%

/* * Careful! The 8259A is a fragile beast, it pretty * much _has_ to be done exactly like this (mask it * first, _then_ send the EOI, and the order of EOI * to the two 8259s is important! */
void sni_rm200_mask_and_ack_8259A(struct irq_data *d) { unsigned int irqmask, irq = d->irq - RM200_I8259A_IRQ_BASE; unsigned long flags; irqmask = 1 << irq; raw_spin_lock_irqsave(&sni_rm200_i8259A_lock, flags); /* * Lightweight spurious IRQ detection. We do not want * to overdo spurious IRQ handling - it's usually a sign * of hardware problems, so we only do the checks we can * do without slowing down good hardware unnecessarily. * * Note that IRQ7 and IRQ15 (the two spurious IRQs * usually resulting from the 8259A-1|2 PICs) occur * even if the IRQ is masked in the 8259A. Thus we * can check spurious 8259A IRQs without doing the * quite slow i8259A_irq_real() call for every IRQ. * This does not cover 100% of spurious interrupts, * but should be enough to warn the user that there * is something bad going on ... */ if (rm200_cached_irq_mask & irqmask) goto spurious_8259A_irq; rm200_cached_irq_mask |= irqmask; handle_real_irq: if (irq & 8) { readb(rm200_pic_slave + PIC_IMR); writeb(cached_slave_mask, rm200_pic_slave + PIC_IMR); writeb(0x60+(irq & 7), rm200_pic_slave + PIC_CMD); writeb(0x60+PIC_CASCADE_IR, rm200_pic_master + PIC_CMD); } else { readb(rm200_pic_master + PIC_IMR); writeb(cached_master_mask, rm200_pic_master + PIC_IMR); writeb(0x60+irq, rm200_pic_master + PIC_CMD); } raw_spin_unlock_irqrestore(&sni_rm200_i8259A_lock, flags); return; spurious_8259A_irq: /* * this is the slow path - should happen rarely. */ if (sni_rm200_i8259A_irq_real(irq)) /* * oops, the IRQ _is_ in service according to the * 8259A - not spurious, go handle it. */ goto handle_real_irq; { static int spurious_irq_mask; /* * At this point we can be sure the IRQ is spurious, * let's ACK and report it. [once per IRQ] */ if (!(spurious_irq_mask & irqmask)) { printk(KERN_DEBUG "spurious RM200 8259A interrupt: IRQ%d.\n", irq); spurious_irq_mask |= irqmask; } atomic_inc(&irq_err_count); /* * Theoretically we do not have to handle this IRQ, * but in Linux this does not cause problems and is * simpler for us. */ goto handle_real_irq; } }

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Thomas Bogendoerfer18492.46%125.00%
Thomas Gleixner126.03%125.00%
Ralf Bächle31.51%250.00%
Total199100.00%4100.00%

static struct irq_chip sni_rm200_i8259A_chip = { .name = "RM200-XT-PIC", .irq_mask = sni_rm200_disable_8259A_irq, .irq_unmask = sni_rm200_enable_8259A_irq, .irq_mask_ack = sni_rm200_mask_and_ack_8259A, }; /* * Do the traditional i8259 interrupt polling thing. This is for the few * cases where no better interrupt acknowledge method is available and we * absolutely must touch the i8259. */
static inline int sni_rm200_i8259_irq(void) { int irq; raw_spin_lock(&sni_rm200_i8259A_lock); /* Perform an interrupt acknowledge cycle on controller 1. */ writeb(0x0C, rm200_pic_master + PIC_CMD); /* prepare for poll */ irq = readb(rm200_pic_master + PIC_CMD) & 7; if (irq == PIC_CASCADE_IR) { /* * Interrupt is cascaded so perform interrupt * acknowledge on controller 2. */ writeb(0x0C, rm200_pic_slave + PIC_CMD); /* prepare for poll */ irq = (readb(rm200_pic_slave + PIC_CMD) & 7) + 8; } if (unlikely(irq == 7)) { /* * This may be a spurious interrupt. * * Read the interrupt status register (ISR). If the most * significant bit is not set then there is no valid * interrupt. */ writeb(0x0B, rm200_pic_master + PIC_ISR); /* ISR register */ if (~readb(rm200_pic_master + PIC_ISR) & 0x80) irq = -1; } raw_spin_unlock(&sni_rm200_i8259A_lock); return likely(irq >= 0) ? irq + RM200_I8259A_IRQ_BASE : irq; }

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Thomas Bogendoerfer13198.50%150.00%
Ralf Bächle21.50%150.00%
Total133100.00%2100.00%


void sni_rm200_init_8259A(void) { unsigned long flags; raw_spin_lock_irqsave(&sni_rm200_i8259A_lock, flags); writeb(0xff, rm200_pic_master + PIC_IMR); writeb(0xff, rm200_pic_slave + PIC_IMR); writeb(0x11, rm200_pic_master + PIC_CMD); writeb(0, rm200_pic_master + PIC_IMR); writeb(1U << PIC_CASCADE_IR, rm200_pic_master + PIC_IMR); writeb(MASTER_ICW4_DEFAULT, rm200_pic_master + PIC_IMR); writeb(0x11, rm200_pic_slave + PIC_CMD); writeb(8, rm200_pic_slave + PIC_IMR); writeb(PIC_CASCADE_IR, rm200_pic_slave + PIC_IMR); writeb(SLAVE_ICW4_DEFAULT, rm200_pic_slave + PIC_IMR); udelay(100); /* wait for 8259A to initialize */ writeb(cached_master_mask, rm200_pic_master + PIC_IMR); writeb(cached_slave_mask, rm200_pic_slave + PIC_IMR); raw_spin_unlock_irqrestore(&sni_rm200_i8259A_lock, flags); }

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Thomas Bogendoerfer14198.60%150.00%
Ralf Bächle21.40%150.00%
Total143100.00%2100.00%

/* * IRQ2 is cascade interrupt to second interrupt controller */ static struct irqaction sni_rm200_irq2 = { .handler = no_action, .name = "cascade", .flags = IRQF_NO_THREAD, }; static struct resource sni_rm200_pic1_resource = { .name = "onboard ISA pic1", .start = 0x16000020, .end = 0x16000023, .flags = IORESOURCE_BUSY }; static struct resource sni_rm200_pic2_resource = { .name = "onboard ISA pic2", .start = 0x160000a0, .end = 0x160000a3, .flags = IORESOURCE_BUSY }; /* ISA irq handler */
static irqreturn_t sni_rm200_i8259A_irq_handler(int dummy, void *p) { int irq; irq = sni_rm200_i8259_irq(); if (unlikely(irq < 0)) return IRQ_NONE; do_IRQ(irq); return IRQ_HANDLED; }

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Thomas Bogendoerfer41100.00%1100.00%
Total41100.00%1100.00%

struct irqaction sni_rm200_i8259A_irq = { .handler = sni_rm200_i8259A_irq_handler, .name = "onboard ISA", .flags = IRQF_SHARED };
void __init sni_rm200_i8259_irqs(void) { int i; rm200_pic_master = ioremap_nocache(0x16000020, 4); if (!rm200_pic_master) return; rm200_pic_slave = ioremap_nocache(0x160000a0, 4); if (!rm200_pic_slave) { iounmap(rm200_pic_master); return; } insert_resource(&iomem_resource, &sni_rm200_pic1_resource); insert_resource(&iomem_resource, &sni_rm200_pic2_resource); sni_rm200_init_8259A(); for (i = RM200_I8259A_IRQ_BASE; i < RM200_I8259A_IRQ_BASE + 16; i++) irq_set_chip_and_handler(i, &sni_rm200_i8259A_chip, handle_level_irq); setup_irq(RM200_I8259A_IRQ_BASE + PIC_CASCADE_IR, &sni_rm200_irq2); }

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Thomas Bogendoerfer10298.08%133.33%
Julia Lawall10.96%133.33%
Thomas Gleixner10.96%133.33%
Total104100.00%3100.00%

#define SNI_RM200_INT_STAT_REG CKSEG1ADDR(0xbc000000) #define SNI_RM200_INT_ENA_REG CKSEG1ADDR(0xbc080000) #define SNI_RM200_INT_START 24 #define SNI_RM200_INT_END 28
static void enable_rm200_irq(struct irq_data *d) { unsigned int mask = 1 << (d->irq - SNI_RM200_INT_START); *(volatile u8 *)SNI_RM200_INT_ENA_REG &= ~mask; }

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Thomas Bogendoerfer3083.33%150.00%
Thomas Gleixner616.67%150.00%
Total36100.00%2100.00%


void disable_rm200_irq(struct irq_data *d) { unsigned int mask = 1 << (d->irq - SNI_RM200_INT_START); *(volatile u8 *)SNI_RM200_INT_ENA_REG |= mask; }

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Thomas Bogendoerfer2882.35%150.00%
Thomas Gleixner617.65%150.00%
Total34100.00%2100.00%

static struct irq_chip rm200_irq_type = { .name = "RM200", .irq_mask = disable_rm200_irq, .irq_unmask = enable_rm200_irq, };
static void sni_rm200_hwint(void) { u32 pending = read_c0_cause() & read_c0_status(); u8 mask; u8 stat; int irq; if (pending & C_IRQ5) do_IRQ(MIPS_CPU_IRQ_BASE + 7); else if (pending & C_IRQ0) { clear_c0_status(IE_IRQ0); mask = *(volatile u8 *)SNI_RM200_INT_ENA_REG ^ 0x1f; stat = *(volatile u8 *)SNI_RM200_INT_STAT_REG ^ 0x14; irq = ffs(stat & mask & 0x1f); if (likely(irq > 0)) do_IRQ(irq + SNI_RM200_INT_START - 1); set_c0_status(IE_IRQ0); } }

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Thomas Bogendoerfer111100.00%2100.00%
Total111100.00%2100.00%


void __init sni_rm200_irq_init(void) { int i; * (volatile u8 *)SNI_RM200_INT_ENA_REG = 0x1f; sni_rm200_i8259_irqs(); mips_cpu_irq_init(); /* Actually we've got more interrupts to handle ... */ for (i = SNI_RM200_INT_START; i <= SNI_RM200_INT_END; i++) irq_set_chip_and_handler(i, &rm200_irq_type, handle_level_irq); sni_hwint = sni_rm200_hwint; change_c0_status(ST0_IM, IE_IRQ0); setup_irq(SNI_RM200_INT_START + 0, &sni_rm200_i8259A_irq); setup_irq(SNI_RM200_INT_START + 1, &sni_isa_irq); }

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Thomas Bogendoerfer7996.34%250.00%
Ralf Bächle22.44%125.00%
Thomas Gleixner11.22%125.00%
Total82100.00%4100.00%


void __init sni_rm200_init(void) { }

Contributors

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Thomas Bogendoerfer7100.00%3100.00%
Total7100.00%3100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
Thomas Bogendoerfer167195.05%531.25%
Thomas Gleixner563.19%318.75%
Ralf Bächle150.85%425.00%
Rusty Russell70.40%16.25%
Wu Zhangjin50.28%16.25%
David Howells30.17%16.25%
Julia Lawall10.06%16.25%
Total1758100.00%16100.00%
Directory: arch/mips/sni
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