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Release 4.14 arch/powerpc/platforms/52xx/mpc52xx_pic.c

/*
 *
 * Programmable Interrupt Controller functions for the Freescale MPC52xx.
 *
 * Copyright (C) 2008 Secret Lab Technologies Ltd.
 * Copyright (C) 2006 bplan GmbH
 * Copyright (C) 2004 Sylvain Munaut <tnt@246tNt.com>
 * Copyright (C) 2003 Montavista Software, Inc
 *
 * Based on the code from the 2.4 kernel by
 * Dale Farnsworth <dfarnsworth@mvista.com> and Kent Borg.
 *
 * This file is licensed under the terms of the GNU General Public License
 * version 2. This program is licensed "as is" without any warranty of any
 * kind, whether express or implied.
 *
 */

/*
 * This is the device driver for the MPC5200 interrupt controller.
 *
 * hardware overview
 * -----------------
 * The MPC5200 interrupt controller groups the all interrupt sources into
 * three groups called 'critical', 'main', and 'peripheral'.  The critical
 * group has 3 irqs, External IRQ0, slice timer 0 irq, and wake from deep
 * sleep.  Main group include the other 3 external IRQs, slice timer 1, RTC,
 * gpios, and the general purpose timers.  Peripheral group contains the
 * remaining irq sources from all of the on-chip peripherals (PSCs, Ethernet,
 * USB, DMA, etc).
 *
 * virqs
 * -----
 * The Linux IRQ subsystem requires that each irq source be assigned a
 * system wide unique IRQ number starting at 1 (0 means no irq).  Since
 * systems can have multiple interrupt controllers, the virtual IRQ (virq)
 * infrastructure lets each interrupt controller to define a local set
 * of IRQ numbers and the virq infrastructure maps those numbers into
 * a unique range of the global IRQ# space.
 *
 * To define a range of virq numbers for this controller, this driver first
 * assigns a number to each of the irq groups (called the level 1 or L1
 * value).  Within each group individual irq sources are also assigned a
 * number, as defined by the MPC5200 user guide, and refers to it as the
 * level 2 or L2 value.  The virq number is determined by shifting up the
 * L1 value by MPC52xx_IRQ_L1_OFFSET and ORing it with the L2 value.
 *
 * For example, the TMR0 interrupt is irq 9 in the main group.  The
 * virq for TMR0 is calculated by ((1 << MPC52xx_IRQ_L1_OFFSET) | 9).
 *
 * The observant reader will also notice that this driver defines a 4th
 * interrupt group called 'bestcomm'.  The bestcomm group isn't physically
 * part of the MPC5200 interrupt controller, but it is used here to assign
 * a separate virq number for each bestcomm task (since any of the 16
 * bestcomm tasks can cause the bestcomm interrupt to be raised).  When a
 * bestcomm interrupt occurs (peripheral group, irq 0) this driver determines
 * which task needs servicing and returns the irq number for that task.  This
 * allows drivers which use bestcomm to define their own interrupt handlers.
 *
 * irq_chip structures
 * -------------------
 * For actually manipulating IRQs (masking, enabling, clearing, etc) this
 * driver defines four separate 'irq_chip' structures, one for the main
 * group, one for the peripherals group, one for the bestcomm group and one
 * for external interrupts.  The irq_chip structures provide the hooks needed
 * to manipulate each IRQ source, and since each group is has a separate set
 * of registers for controlling the irq, it makes sense to divide up the
 * hooks along those lines.
 *
 * You'll notice that there is not an irq_chip for the critical group and
 * you'll also notice that there is an irq_chip defined for external
 * interrupts even though there is no external interrupt group.  The reason
 * for this is that the four external interrupts are all managed with the same
 * register even though one of the external IRQs is in the critical group and
 * the other three are in the main group.  For this reason it makes sense for
 * the 4 external irqs to be managed using a separate set of hooks.  The
 * reason there is no crit irq_chip is that of the 3 irqs in the critical
 * group, only external interrupt is actually support at this time by this
 * driver and since external interrupt is the only one used, it can just
 * be directed to make use of the external irq irq_chip.
 *
 * device tree bindings
 * --------------------
 * The device tree bindings for this controller reflect the two level
 * organization of irqs in the device.  #interrupt-cells = <3> where the
 * first cell is the group number [0..3], the second cell is the irq
 * number in the group, and the third cell is the sense type (level/edge).
 * For reference, the following is a list of the interrupt property values
 * associated with external interrupt sources on the MPC5200 (just because
 * it is non-obvious to determine what the interrupts property should be
 * when reading the mpc5200 manual and it is a frequently asked question).
 *
 * External interrupts:
 * <0 0 n>      external irq0, n is sense       (n=0: level high,
 * <1 1 n>      external irq1, n is sense        n=1: edge rising,
 * <1 2 n>      external irq2, n is sense        n=2: edge falling,
 * <1 3 n>      external irq3, n is sense        n=3: level low)
 */

#undef DEBUG

#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/of.h>
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/mpc52xx.h>

/* HW IRQ mapping */

#define MPC52xx_IRQ_L1_CRIT	(0)

#define MPC52xx_IRQ_L1_MAIN	(1)

#define MPC52xx_IRQ_L1_PERP	(2)

#define MPC52xx_IRQ_L1_SDMA	(3)


#define MPC52xx_IRQ_L1_OFFSET	(6)

#define MPC52xx_IRQ_L1_MASK	(0x00c0)

#define MPC52xx_IRQ_L2_MASK	(0x003f)


#define MPC52xx_IRQ_HIGHTESTHWIRQ (0xd0)


/* MPC5200 device tree match tables */

static const struct of_device_id mpc52xx_pic_ids[] __initconst = {
	{ .compatible = "fsl,mpc5200-pic", },
	{ .compatible = "mpc5200-pic", },
	{}
};

static const struct of_device_id mpc52xx_sdma_ids[] __initconst = {
	{ .compatible = "fsl,mpc5200-bestcomm", },
	{ .compatible = "mpc5200-bestcomm", },
	{}
};


static struct mpc52xx_intr __iomem *intr;

static struct mpc52xx_sdma __iomem *sdma;

static struct irq_domain *mpc52xx_irqhost = NULL;


static unsigned char mpc52xx_map_senses[4] = {
	IRQ_TYPE_LEVEL_HIGH,
	IRQ_TYPE_EDGE_RISING,
	IRQ_TYPE_EDGE_FALLING,
	IRQ_TYPE_LEVEL_LOW,
};

/* Utility functions */

static inline void io_be_setbit(u32 __iomem *addr, int bitno) { out_be32(addr, in_be32(addr) | (1 << bitno)); }

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static inline void io_be_clrbit(u32 __iomem *addr, int bitno) { out_be32(addr, in_be32(addr) & ~(1 << bitno)); }

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/* * IRQ[0-3] interrupt irq_chip */
static void mpc52xx_extirq_mask(struct irq_data *d) { int l2irq = irqd_to_hwirq(d) & MPC52xx_IRQ_L2_MASK; io_be_clrbit(&intr->ctrl, 11 - l2irq); }

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static void mpc52xx_extirq_unmask(struct irq_data *d) { int l2irq = irqd_to_hwirq(d) & MPC52xx_IRQ_L2_MASK; io_be_setbit(&intr->ctrl, 11 - l2irq); }

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static void mpc52xx_extirq_ack(struct irq_data *d) { int l2irq = irqd_to_hwirq(d) & MPC52xx_IRQ_L2_MASK; io_be_setbit(&intr->ctrl, 27-l2irq); }

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static int mpc52xx_extirq_set_type(struct irq_data *d, unsigned int flow_type) { u32 ctrl_reg, type; int l2irq = irqd_to_hwirq(d) & MPC52xx_IRQ_L2_MASK; void *handler = handle_level_irq; pr_debug("%s: irq=%x. l2=%d flow_type=%d\n", __func__, (int) irqd_to_hwirq(d), l2irq, flow_type); switch (flow_type) { case IRQF_TRIGGER_HIGH: type = 0; break; case IRQF_TRIGGER_RISING: type = 1; handler = handle_edge_irq; break; case IRQF_TRIGGER_FALLING: type = 2; handler = handle_edge_irq; break; case IRQF_TRIGGER_LOW: type = 3; break; default: type = 0; } ctrl_reg = in_be32(&intr->ctrl); ctrl_reg &= ~(0x3 << (22 - (l2irq * 2))); ctrl_reg |= (type << (22 - (l2irq * 2))); out_be32(&intr->ctrl, ctrl_reg); irq_set_handler_locked(d, handler); return 0; }

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Total169100.00%5100.00%

static struct irq_chip mpc52xx_extirq_irqchip = { .name = "MPC52xx External", .irq_mask = mpc52xx_extirq_mask, .irq_unmask = mpc52xx_extirq_unmask, .irq_ack = mpc52xx_extirq_ack, .irq_set_type = mpc52xx_extirq_set_type, }; /* * Main interrupt irq_chip */
static int mpc52xx_null_set_type(struct irq_data *d, unsigned int flow_type) { return 0; /* Do nothing so that the sense mask will get updated */ }

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static void mpc52xx_main_mask(struct irq_data *d) { int l2irq = irqd_to_hwirq(d) & MPC52xx_IRQ_L2_MASK; io_be_setbit(&intr->main_mask, 16 - l2irq); }

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static void mpc52xx_main_unmask(struct irq_data *d) { int l2irq = irqd_to_hwirq(d) & MPC52xx_IRQ_L2_MASK; io_be_clrbit(&intr->main_mask, 16 - l2irq); }

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static struct irq_chip mpc52xx_main_irqchip = { .name = "MPC52xx Main", .irq_mask = mpc52xx_main_mask, .irq_mask_ack = mpc52xx_main_mask, .irq_unmask = mpc52xx_main_unmask, .irq_set_type = mpc52xx_null_set_type, }; /* * Peripherals interrupt irq_chip */
static void mpc52xx_periph_mask(struct irq_data *d) { int l2irq = irqd_to_hwirq(d) & MPC52xx_IRQ_L2_MASK; io_be_setbit(&intr->per_mask, 31 - l2irq); }

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static void mpc52xx_periph_unmask(struct irq_data *d) { int l2irq = irqd_to_hwirq(d) & MPC52xx_IRQ_L2_MASK; io_be_clrbit(&intr->per_mask, 31 - l2irq); }

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static struct irq_chip mpc52xx_periph_irqchip = { .name = "MPC52xx Peripherals", .irq_mask = mpc52xx_periph_mask, .irq_mask_ack = mpc52xx_periph_mask, .irq_unmask = mpc52xx_periph_unmask, .irq_set_type = mpc52xx_null_set_type, }; /* * SDMA interrupt irq_chip */
static void mpc52xx_sdma_mask(struct irq_data *d) { int l2irq = irqd_to_hwirq(d) & MPC52xx_IRQ_L2_MASK; io_be_setbit(&sdma->IntMask, l2irq); }

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static void mpc52xx_sdma_unmask(struct irq_data *d) { int l2irq = irqd_to_hwirq(d) & MPC52xx_IRQ_L2_MASK; io_be_clrbit(&sdma->IntMask, l2irq); }

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static void mpc52xx_sdma_ack(struct irq_data *d) { int l2irq = irqd_to_hwirq(d) & MPC52xx_IRQ_L2_MASK; out_be32(&sdma->IntPend, 1 << l2irq); }

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static struct irq_chip mpc52xx_sdma_irqchip = { .name = "MPC52xx SDMA", .irq_mask = mpc52xx_sdma_mask, .irq_unmask = mpc52xx_sdma_unmask, .irq_ack = mpc52xx_sdma_ack, .irq_set_type = mpc52xx_null_set_type, }; /** * mpc52xx_is_extirq - Returns true if hwirq number is for an external IRQ */
static int mpc52xx_is_extirq(int l1, int l2) { return ((l1 == 0) && (l2 == 0)) || ((l1 == 1) && (l2 >= 1) && (l2 <= 3)); }

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/** * mpc52xx_irqhost_xlate - translate virq# from device tree interrupts property */
static int mpc52xx_irqhost_xlate(struct irq_domain *h, struct device_node *ct, const u32 *intspec, unsigned int intsize, irq_hw_number_t *out_hwirq, unsigned int *out_flags) { int intrvect_l1; int intrvect_l2; int intrvect_type; int intrvect_linux; if (intsize != 3) return -1; intrvect_l1 = (int)intspec[0]; intrvect_l2 = (int)intspec[1]; intrvect_type = (int)intspec[2] & 0x3; intrvect_linux = (intrvect_l1 << MPC52xx_IRQ_L1_OFFSET) & MPC52xx_IRQ_L1_MASK; intrvect_linux |= intrvect_l2 & MPC52xx_IRQ_L2_MASK; *out_hwirq = intrvect_linux; *out_flags = IRQ_TYPE_LEVEL_LOW; if (mpc52xx_is_extirq(intrvect_l1, intrvect_l2)) *out_flags = mpc52xx_map_senses[intrvect_type]; pr_debug("return %x, l1=%d, l2=%d\n", intrvect_linux, intrvect_l1, intrvect_l2); return 0; }

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/** * mpc52xx_irqhost_map - Hook to map from virq to an irq_chip structure */
static int mpc52xx_irqhost_map(struct irq_domain *h, unsigned int virq, irq_hw_number_t irq) { int l1irq; int l2irq; struct irq_chip *uninitialized_var(irqchip); void *hndlr; int type; u32 reg; l1irq = (irq & MPC52xx_IRQ_L1_MASK) >> MPC52xx_IRQ_L1_OFFSET; l2irq = irq & MPC52xx_IRQ_L2_MASK; /* * External IRQs are handled differently by the hardware so they are * handled by a dedicated irq_chip structure. */ if (mpc52xx_is_extirq(l1irq, l2irq)) { reg = in_be32(&intr->ctrl); type = mpc52xx_map_senses[(reg >> (22 - l2irq * 2)) & 0x3]; if ((type == IRQ_TYPE_EDGE_FALLING) || (type == IRQ_TYPE_EDGE_RISING)) hndlr = handle_edge_irq; else hndlr = handle_level_irq; irq_set_chip_and_handler(virq, &mpc52xx_extirq_irqchip, hndlr); pr_debug("%s: External IRQ%i virq=%x, hw=%x. type=%x\n", __func__, l2irq, virq, (int)irq, type); return 0; } /* It is an internal SOC irq. Choose the correct irq_chip */ switch (l1irq) { case MPC52xx_IRQ_L1_MAIN: irqchip = &mpc52xx_main_irqchip; break; case MPC52xx_IRQ_L1_PERP: irqchip = &mpc52xx_periph_irqchip; break; case MPC52xx_IRQ_L1_SDMA: irqchip = &mpc52xx_sdma_irqchip; break; case MPC52xx_IRQ_L1_CRIT: pr_warn("%s: Critical IRQ #%d is unsupported! Nopping it.\n", __func__, l2irq); irq_set_chip(virq, &no_irq_chip); return 0; } irq_set_chip_and_handler(virq, irqchip, handle_level_irq); pr_debug("%s: virq=%x, l1=%i, l2=%i\n", __func__, virq, l1irq, l2irq); return 0; }

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Total235100.00%7100.00%

static const struct irq_domain_ops mpc52xx_irqhost_ops = { .xlate = mpc52xx_irqhost_xlate, .map = mpc52xx_irqhost_map, }; /** * mpc52xx_init_irq - Initialize and register with the virq subsystem * * Hook for setting up IRQs on an mpc5200 system. A pointer to this function * is to be put into the machine definition structure. * * This function searches the device tree for an MPC5200 interrupt controller, * initializes it, and registers it with the virq subsystem. */
void __init mpc52xx_init_irq(void) { u32 intr_ctrl; struct device_node *picnode; struct device_node *np; /* Remap the necessary zones */ picnode = of_find_matching_node(NULL, mpc52xx_pic_ids); intr = of_iomap(picnode, 0); if (!intr) panic(__FILE__ ": find_and_map failed on 'mpc5200-pic'. " "Check node !"); np = of_find_matching_node(NULL, mpc52xx_sdma_ids); sdma = of_iomap(np, 0); of_node_put(np); if (!sdma) panic(__FILE__ ": find_and_map failed on 'mpc5200-bestcomm'. " "Check node !"); pr_debug("MPC5200 IRQ controller mapped to 0x%p\n", intr); /* Disable all interrupt sources. */ out_be32(&sdma->IntPend, 0xffffffff); /* 1 means clear pending */ out_be32(&sdma->IntMask, 0xffffffff); /* 1 means disabled */ out_be32(&intr->per_mask, 0x7ffffc00); /* 1 means disabled */ out_be32(&intr->main_mask, 0x00010fff); /* 1 means disabled */ intr_ctrl = in_be32(&intr->ctrl); intr_ctrl &= 0x00ff0000; /* Keeps IRQ[0-3] config */ intr_ctrl |= 0x0f000000 | /* clear IRQ 0-3 */ 0x00001000 | /* MEE master external enable */ 0x00000000 | /* 0 means disable IRQ 0-3 */ 0x00000001; /* CEb route critical normally */ out_be32(&intr->ctrl, intr_ctrl); /* Zero a bunch of the priority settings. */ out_be32(&intr->per_pri1, 0); out_be32(&intr->per_pri2, 0); out_be32(&intr->per_pri3, 0); out_be32(&intr->main_pri1, 0); out_be32(&intr->main_pri2, 0); /* * As last step, add an irq host to translate the real * hw irq information provided by the ofw to linux virq */ mpc52xx_irqhost = irq_domain_add_linear(picnode, MPC52xx_IRQ_HIGHTESTHWIRQ, &mpc52xx_irqhost_ops, NULL); if (!mpc52xx_irqhost) panic(__FILE__ ": Cannot allocate the IRQ host\n"); irq_set_default_host(mpc52xx_irqhost); pr_info("MPC52xx PIC is up and running!\n"); }

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/** * mpc52xx_get_irq - Get pending interrupt number hook function * * Called by the interrupt handler to determine what IRQ handler needs to be * executed. * * Status of pending interrupts is determined by reading the encoded status * register. The encoded status register has three fields; one for each of the * types of interrupts defined by the controller - 'critical', 'main' and * 'peripheral'. This function reads the status register and returns the IRQ * number associated with the highest priority pending interrupt. 'Critical' * interrupts have the highest priority, followed by 'main' interrupts, and * then 'peripheral'. * * The mpc5200 interrupt controller can be configured to boost the priority * of individual 'peripheral' interrupts. If this is the case then a special * value will appear in either the crit or main fields indicating a high * or medium priority peripheral irq has occurred. * * This function checks each of the 3 irq request fields and returns the * first pending interrupt that it finds. * * This function also identifies a 4th type of interrupt; 'bestcomm'. Each * bestcomm DMA task can raise the bestcomm peripheral interrupt. When this * occurs at task-specific IRQ# is decoded so that each task can have its * own IRQ handler. */
unsigned int mpc52xx_get_irq(void) { u32 status; int irq; status = in_be32(&intr->enc_status); if (status & 0x00000400) { /* critical */ irq = (status >> 8) & 0x3; if (irq == 2) /* high priority peripheral */ goto peripheral; irq |= (MPC52xx_IRQ_L1_CRIT << MPC52xx_IRQ_L1_OFFSET); } else if (status & 0x00200000) { /* main */ irq = (status >> 16) & 0x1f; if (irq == 4) /* low priority peripheral */ goto peripheral; irq |= (MPC52xx_IRQ_L1_MAIN << MPC52xx_IRQ_L1_OFFSET); } else if (status & 0x20000000) { /* peripheral */ peripheral: irq = (status >> 24) & 0x1f; if (irq == 0) { /* bestcomm */ status = in_be32(&sdma->IntPend); irq = ffs(status) - 1; irq |= (MPC52xx_IRQ_L1_SDMA << MPC52xx_IRQ_L1_OFFSET); } else { irq |= (MPC52xx_IRQ_L1_PERP << MPC52xx_IRQ_L1_OFFSET); } } else { return 0; } return irq_linear_revmap(mpc52xx_irqhost, irq); }

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Grant C. Likely21.10%125.00%
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Total182100.00%4100.00%


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Sascha Hauer1377.80%13.57%
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Wolfram Sang160.91%27.14%
Thomas Gleixner70.40%310.71%
Milton D. Miller II50.28%13.57%
Uwe Kleine-König40.23%13.57%
Michael Ellerman30.17%27.14%
Domen Puncer20.11%13.57%
Lucas De Marchi10.06%13.57%
Roman Fietze10.06%13.57%
Total1756100.00%28100.00%
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