/* * * 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 * Copyright (C) 2003 Montavista Software, Inc * * Based on the code from the 2.4 kernel by * Dale Farnsworth 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 #include #include #include #include #include #include /* 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)); } static inline void io_be_clrbit(u32 __iomem *addr, int bitno) { out_be32(addr, in_be32(addr) & ~(1 << bitno)); } /* * 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); } 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); } 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); } 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; } 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 */ } 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); } 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); } 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); } 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); } 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); } 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); } 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); } 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)); } /** * 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; } /** * 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 *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; } 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"); } /** * 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); }