diff options
Diffstat (limited to 'drivers/irqchip/irq-pruss-intc.c')
-rw-r--r-- | drivers/irqchip/irq-pruss-intc.c | 664 |
1 files changed, 664 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-pruss-intc.c b/drivers/irqchip/irq-pruss-intc.c new file mode 100644 index 000000000..92fb5780d --- /dev/null +++ b/drivers/irqchip/irq-pruss-intc.c @@ -0,0 +1,664 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * PRU-ICSS INTC IRQChip driver for various TI SoCs + * + * Copyright (C) 2016-2020 Texas Instruments Incorporated - http://www.ti.com/ + * + * Author(s): + * Andrew F. Davis <afd@ti.com> + * Suman Anna <s-anna@ti.com> + * Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org> for Texas Instruments + * + * Copyright (C) 2019 David Lechner <david@lechnology.com> + */ + +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/irqchip/chained_irq.h> +#include <linux/irqdomain.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> + +/* + * Number of host interrupts reaching the main MPU sub-system. Note that this + * is not the same as the total number of host interrupts supported by the PRUSS + * INTC instance + */ +#define MAX_NUM_HOST_IRQS 8 + +/* minimum starting host interrupt number for MPU */ +#define FIRST_PRU_HOST_INT 2 + +/* PRU_ICSS_INTC registers */ +#define PRU_INTC_REVID 0x0000 +#define PRU_INTC_CR 0x0004 +#define PRU_INTC_GER 0x0010 +#define PRU_INTC_GNLR 0x001c +#define PRU_INTC_SISR 0x0020 +#define PRU_INTC_SICR 0x0024 +#define PRU_INTC_EISR 0x0028 +#define PRU_INTC_EICR 0x002c +#define PRU_INTC_HIEISR 0x0034 +#define PRU_INTC_HIDISR 0x0038 +#define PRU_INTC_GPIR 0x0080 +#define PRU_INTC_SRSR(x) (0x0200 + (x) * 4) +#define PRU_INTC_SECR(x) (0x0280 + (x) * 4) +#define PRU_INTC_ESR(x) (0x0300 + (x) * 4) +#define PRU_INTC_ECR(x) (0x0380 + (x) * 4) +#define PRU_INTC_CMR(x) (0x0400 + (x) * 4) +#define PRU_INTC_HMR(x) (0x0800 + (x) * 4) +#define PRU_INTC_HIPIR(x) (0x0900 + (x) * 4) +#define PRU_INTC_SIPR(x) (0x0d00 + (x) * 4) +#define PRU_INTC_SITR(x) (0x0d80 + (x) * 4) +#define PRU_INTC_HINLR(x) (0x1100 + (x) * 4) +#define PRU_INTC_HIER 0x1500 + +/* CMR register bit-field macros */ +#define CMR_EVT_MAP_MASK 0xf +#define CMR_EVT_MAP_BITS 8 +#define CMR_EVT_PER_REG 4 + +/* HMR register bit-field macros */ +#define HMR_CH_MAP_MASK 0xf +#define HMR_CH_MAP_BITS 8 +#define HMR_CH_PER_REG 4 + +/* HIPIR register bit-fields */ +#define INTC_HIPIR_NONE_HINT 0x80000000 + +#define MAX_PRU_SYS_EVENTS 160 +#define MAX_PRU_CHANNELS 20 + +/** + * struct pruss_intc_map_record - keeps track of actual mapping state + * @value: The currently mapped value (channel or host) + * @ref_count: Keeps track of number of current users of this resource + */ +struct pruss_intc_map_record { + u8 value; + u8 ref_count; +}; + +/** + * struct pruss_intc_match_data - match data to handle SoC variations + * @num_system_events: number of input system events handled by the PRUSS INTC + * @num_host_events: number of host events (which is equal to number of + * channels) supported by the PRUSS INTC + */ +struct pruss_intc_match_data { + u8 num_system_events; + u8 num_host_events; +}; + +/** + * struct pruss_intc - PRUSS interrupt controller structure + * @event_channel: current state of system event to channel mappings + * @channel_host: current state of channel to host mappings + * @irqs: kernel irq numbers corresponding to PRUSS host interrupts + * @base: base virtual address of INTC register space + * @domain: irq domain for this interrupt controller + * @soc_config: cached PRUSS INTC IP configuration data + * @dev: PRUSS INTC device pointer + * @lock: mutex to serialize interrupts mapping + */ +struct pruss_intc { + struct pruss_intc_map_record event_channel[MAX_PRU_SYS_EVENTS]; + struct pruss_intc_map_record channel_host[MAX_PRU_CHANNELS]; + unsigned int irqs[MAX_NUM_HOST_IRQS]; + void __iomem *base; + struct irq_domain *domain; + const struct pruss_intc_match_data *soc_config; + struct device *dev; + struct mutex lock; /* PRUSS INTC lock */ +}; + +/** + * struct pruss_host_irq_data - PRUSS host irq data structure + * @intc: PRUSS interrupt controller pointer + * @host_irq: host irq number + */ +struct pruss_host_irq_data { + struct pruss_intc *intc; + u8 host_irq; +}; + +static inline u32 pruss_intc_read_reg(struct pruss_intc *intc, unsigned int reg) +{ + return readl_relaxed(intc->base + reg); +} + +static inline void pruss_intc_write_reg(struct pruss_intc *intc, + unsigned int reg, u32 val) +{ + writel_relaxed(val, intc->base + reg); +} + +static void pruss_intc_update_cmr(struct pruss_intc *intc, unsigned int evt, + u8 ch) +{ + u32 idx, offset, val; + + idx = evt / CMR_EVT_PER_REG; + offset = (evt % CMR_EVT_PER_REG) * CMR_EVT_MAP_BITS; + + val = pruss_intc_read_reg(intc, PRU_INTC_CMR(idx)); + val &= ~(CMR_EVT_MAP_MASK << offset); + val |= ch << offset; + pruss_intc_write_reg(intc, PRU_INTC_CMR(idx), val); + + dev_dbg(intc->dev, "SYSEV%u -> CH%d (CMR%d 0x%08x)\n", evt, ch, + idx, pruss_intc_read_reg(intc, PRU_INTC_CMR(idx))); +} + +static void pruss_intc_update_hmr(struct pruss_intc *intc, u8 ch, u8 host) +{ + u32 idx, offset, val; + + idx = ch / HMR_CH_PER_REG; + offset = (ch % HMR_CH_PER_REG) * HMR_CH_MAP_BITS; + + val = pruss_intc_read_reg(intc, PRU_INTC_HMR(idx)); + val &= ~(HMR_CH_MAP_MASK << offset); + val |= host << offset; + pruss_intc_write_reg(intc, PRU_INTC_HMR(idx), val); + + dev_dbg(intc->dev, "CH%d -> HOST%d (HMR%d 0x%08x)\n", ch, host, idx, + pruss_intc_read_reg(intc, PRU_INTC_HMR(idx))); +} + +/** + * pruss_intc_map() - configure the PRUSS INTC + * @intc: PRUSS interrupt controller pointer + * @hwirq: the system event number + * + * Configures the PRUSS INTC with the provided configuration from the one parsed + * in the xlate function. + */ +static void pruss_intc_map(struct pruss_intc *intc, unsigned long hwirq) +{ + struct device *dev = intc->dev; + u8 ch, host, reg_idx; + u32 val; + + mutex_lock(&intc->lock); + + intc->event_channel[hwirq].ref_count++; + + ch = intc->event_channel[hwirq].value; + host = intc->channel_host[ch].value; + + pruss_intc_update_cmr(intc, hwirq, ch); + + reg_idx = hwirq / 32; + val = BIT(hwirq % 32); + + /* clear and enable system event */ + pruss_intc_write_reg(intc, PRU_INTC_ESR(reg_idx), val); + pruss_intc_write_reg(intc, PRU_INTC_SECR(reg_idx), val); + + if (++intc->channel_host[ch].ref_count == 1) { + pruss_intc_update_hmr(intc, ch, host); + + /* enable host interrupts */ + pruss_intc_write_reg(intc, PRU_INTC_HIEISR, host); + } + + dev_dbg(dev, "mapped system_event = %lu channel = %d host = %d", + hwirq, ch, host); + + mutex_unlock(&intc->lock); +} + +/** + * pruss_intc_unmap() - unconfigure the PRUSS INTC + * @intc: PRUSS interrupt controller pointer + * @hwirq: the system event number + * + * Undo whatever was done in pruss_intc_map() for a PRU core. + * Mappings are reference counted, so resources are only disabled when there + * are no longer any users. + */ +static void pruss_intc_unmap(struct pruss_intc *intc, unsigned long hwirq) +{ + u8 ch, host, reg_idx; + u32 val; + + mutex_lock(&intc->lock); + + ch = intc->event_channel[hwirq].value; + host = intc->channel_host[ch].value; + + if (--intc->channel_host[ch].ref_count == 0) { + /* disable host interrupts */ + pruss_intc_write_reg(intc, PRU_INTC_HIDISR, host); + + /* clear the map using reset value 0 */ + pruss_intc_update_hmr(intc, ch, 0); + } + + intc->event_channel[hwirq].ref_count--; + reg_idx = hwirq / 32; + val = BIT(hwirq % 32); + + /* disable system events */ + pruss_intc_write_reg(intc, PRU_INTC_ECR(reg_idx), val); + /* clear any pending status */ + pruss_intc_write_reg(intc, PRU_INTC_SECR(reg_idx), val); + + /* clear the map using reset value 0 */ + pruss_intc_update_cmr(intc, hwirq, 0); + + dev_dbg(intc->dev, "unmapped system_event = %lu channel = %d host = %d\n", + hwirq, ch, host); + + mutex_unlock(&intc->lock); +} + +static void pruss_intc_init(struct pruss_intc *intc) +{ + const struct pruss_intc_match_data *soc_config = intc->soc_config; + int num_chnl_map_regs, num_host_intr_regs, num_event_type_regs, i; + + num_chnl_map_regs = DIV_ROUND_UP(soc_config->num_system_events, + CMR_EVT_PER_REG); + num_host_intr_regs = DIV_ROUND_UP(soc_config->num_host_events, + HMR_CH_PER_REG); + num_event_type_regs = DIV_ROUND_UP(soc_config->num_system_events, 32); + + /* + * configure polarity (SIPR register) to active high and + * type (SITR register) to level interrupt for all system events + */ + for (i = 0; i < num_event_type_regs; i++) { + pruss_intc_write_reg(intc, PRU_INTC_SIPR(i), 0xffffffff); + pruss_intc_write_reg(intc, PRU_INTC_SITR(i), 0); + } + + /* clear all interrupt channel map registers, 4 events per register */ + for (i = 0; i < num_chnl_map_regs; i++) + pruss_intc_write_reg(intc, PRU_INTC_CMR(i), 0); + + /* clear all host interrupt map registers, 4 channels per register */ + for (i = 0; i < num_host_intr_regs; i++) + pruss_intc_write_reg(intc, PRU_INTC_HMR(i), 0); + + /* global interrupt enable */ + pruss_intc_write_reg(intc, PRU_INTC_GER, 1); +} + +static void pruss_intc_irq_ack(struct irq_data *data) +{ + struct pruss_intc *intc = irq_data_get_irq_chip_data(data); + unsigned int hwirq = data->hwirq; + + pruss_intc_write_reg(intc, PRU_INTC_SICR, hwirq); +} + +static void pruss_intc_irq_mask(struct irq_data *data) +{ + struct pruss_intc *intc = irq_data_get_irq_chip_data(data); + unsigned int hwirq = data->hwirq; + + pruss_intc_write_reg(intc, PRU_INTC_EICR, hwirq); +} + +static void pruss_intc_irq_unmask(struct irq_data *data) +{ + struct pruss_intc *intc = irq_data_get_irq_chip_data(data); + unsigned int hwirq = data->hwirq; + + pruss_intc_write_reg(intc, PRU_INTC_EISR, hwirq); +} + +static int pruss_intc_irq_reqres(struct irq_data *data) +{ + if (!try_module_get(THIS_MODULE)) + return -ENODEV; + + return 0; +} + +static void pruss_intc_irq_relres(struct irq_data *data) +{ + module_put(THIS_MODULE); +} + +static int pruss_intc_irq_get_irqchip_state(struct irq_data *data, + enum irqchip_irq_state which, + bool *state) +{ + struct pruss_intc *intc = irq_data_get_irq_chip_data(data); + u32 reg, mask, srsr; + + if (which != IRQCHIP_STATE_PENDING) + return -EINVAL; + + reg = PRU_INTC_SRSR(data->hwirq / 32); + mask = BIT(data->hwirq % 32); + + srsr = pruss_intc_read_reg(intc, reg); + + *state = !!(srsr & mask); + + return 0; +} + +static int pruss_intc_irq_set_irqchip_state(struct irq_data *data, + enum irqchip_irq_state which, + bool state) +{ + struct pruss_intc *intc = irq_data_get_irq_chip_data(data); + + if (which != IRQCHIP_STATE_PENDING) + return -EINVAL; + + if (state) + pruss_intc_write_reg(intc, PRU_INTC_SISR, data->hwirq); + else + pruss_intc_write_reg(intc, PRU_INTC_SICR, data->hwirq); + + return 0; +} + +static struct irq_chip pruss_irqchip = { + .name = "pruss-intc", + .irq_ack = pruss_intc_irq_ack, + .irq_mask = pruss_intc_irq_mask, + .irq_unmask = pruss_intc_irq_unmask, + .irq_request_resources = pruss_intc_irq_reqres, + .irq_release_resources = pruss_intc_irq_relres, + .irq_get_irqchip_state = pruss_intc_irq_get_irqchip_state, + .irq_set_irqchip_state = pruss_intc_irq_set_irqchip_state, +}; + +static int pruss_intc_validate_mapping(struct pruss_intc *intc, int event, + int channel, int host) +{ + struct device *dev = intc->dev; + int ret = 0; + + mutex_lock(&intc->lock); + + /* check if sysevent already assigned */ + if (intc->event_channel[event].ref_count > 0 && + intc->event_channel[event].value != channel) { + dev_err(dev, "event %d (req. ch %d) already assigned to channel %d\n", + event, channel, intc->event_channel[event].value); + ret = -EBUSY; + goto unlock; + } + + /* check if channel already assigned */ + if (intc->channel_host[channel].ref_count > 0 && + intc->channel_host[channel].value != host) { + dev_err(dev, "channel %d (req. host %d) already assigned to host %d\n", + channel, host, intc->channel_host[channel].value); + ret = -EBUSY; + goto unlock; + } + + intc->event_channel[event].value = channel; + intc->channel_host[channel].value = host; + +unlock: + mutex_unlock(&intc->lock); + return ret; +} + +static int +pruss_intc_irq_domain_xlate(struct irq_domain *d, struct device_node *node, + const u32 *intspec, unsigned int intsize, + unsigned long *out_hwirq, unsigned int *out_type) +{ + struct pruss_intc *intc = d->host_data; + struct device *dev = intc->dev; + int ret, sys_event, channel, host; + + if (intsize < 3) + return -EINVAL; + + sys_event = intspec[0]; + if (sys_event < 0 || sys_event >= intc->soc_config->num_system_events) { + dev_err(dev, "%d is not valid event number\n", sys_event); + return -EINVAL; + } + + channel = intspec[1]; + if (channel < 0 || channel >= intc->soc_config->num_host_events) { + dev_err(dev, "%d is not valid channel number", channel); + return -EINVAL; + } + + host = intspec[2]; + if (host < 0 || host >= intc->soc_config->num_host_events) { + dev_err(dev, "%d is not valid host irq number\n", host); + return -EINVAL; + } + + /* check if requested sys_event was already mapped, if so validate it */ + ret = pruss_intc_validate_mapping(intc, sys_event, channel, host); + if (ret) + return ret; + + *out_hwirq = sys_event; + *out_type = IRQ_TYPE_LEVEL_HIGH; + + return 0; +} + +static int pruss_intc_irq_domain_map(struct irq_domain *d, unsigned int virq, + irq_hw_number_t hw) +{ + struct pruss_intc *intc = d->host_data; + + pruss_intc_map(intc, hw); + + irq_set_chip_data(virq, intc); + irq_set_chip_and_handler(virq, &pruss_irqchip, handle_level_irq); + + return 0; +} + +static void pruss_intc_irq_domain_unmap(struct irq_domain *d, unsigned int virq) +{ + struct pruss_intc *intc = d->host_data; + unsigned long hwirq = irqd_to_hwirq(irq_get_irq_data(virq)); + + irq_set_chip_and_handler(virq, NULL, NULL); + irq_set_chip_data(virq, NULL); + pruss_intc_unmap(intc, hwirq); +} + +static const struct irq_domain_ops pruss_intc_irq_domain_ops = { + .xlate = pruss_intc_irq_domain_xlate, + .map = pruss_intc_irq_domain_map, + .unmap = pruss_intc_irq_domain_unmap, +}; + +static void pruss_intc_irq_handler(struct irq_desc *desc) +{ + unsigned int irq = irq_desc_get_irq(desc); + struct irq_chip *chip = irq_desc_get_chip(desc); + struct pruss_host_irq_data *host_irq_data = irq_get_handler_data(irq); + struct pruss_intc *intc = host_irq_data->intc; + u8 host_irq = host_irq_data->host_irq + FIRST_PRU_HOST_INT; + + chained_irq_enter(chip, desc); + + while (true) { + u32 hipir; + unsigned int virq; + int hwirq; + + /* get highest priority pending PRUSS system event */ + hipir = pruss_intc_read_reg(intc, PRU_INTC_HIPIR(host_irq)); + if (hipir & INTC_HIPIR_NONE_HINT) + break; + + hwirq = hipir & GENMASK(9, 0); + virq = irq_find_mapping(intc->domain, hwirq); + + /* + * NOTE: manually ACK any system events that do not have a + * handler mapped yet + */ + if (WARN_ON_ONCE(!virq)) + pruss_intc_write_reg(intc, PRU_INTC_SICR, hwirq); + else + generic_handle_irq(virq); + } + + chained_irq_exit(chip, desc); +} + +static const char * const irq_names[MAX_NUM_HOST_IRQS] = { + "host_intr0", "host_intr1", "host_intr2", "host_intr3", + "host_intr4", "host_intr5", "host_intr6", "host_intr7", +}; + +static int pruss_intc_probe(struct platform_device *pdev) +{ + const struct pruss_intc_match_data *data; + struct device *dev = &pdev->dev; + struct pruss_intc *intc; + struct pruss_host_irq_data *host_data; + int i, irq, ret; + u8 max_system_events, irqs_reserved = 0; + + data = of_device_get_match_data(dev); + if (!data) + return -ENODEV; + + max_system_events = data->num_system_events; + + intc = devm_kzalloc(dev, sizeof(*intc), GFP_KERNEL); + if (!intc) + return -ENOMEM; + + intc->soc_config = data; + intc->dev = dev; + platform_set_drvdata(pdev, intc); + + intc->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(intc->base)) + return PTR_ERR(intc->base); + + ret = of_property_read_u8(dev->of_node, "ti,irqs-reserved", + &irqs_reserved); + + /* + * The irqs-reserved is used only for some SoC's therefore not having + * this property is still valid + */ + if (ret < 0 && ret != -EINVAL) + return ret; + + pruss_intc_init(intc); + + mutex_init(&intc->lock); + + intc->domain = irq_domain_add_linear(dev->of_node, max_system_events, + &pruss_intc_irq_domain_ops, intc); + if (!intc->domain) + return -ENOMEM; + + for (i = 0; i < MAX_NUM_HOST_IRQS; i++) { + if (irqs_reserved & BIT(i)) + continue; + + irq = platform_get_irq_byname(pdev, irq_names[i]); + if (irq <= 0) { + ret = (irq == 0) ? -EINVAL : irq; + goto fail_irq; + } + + intc->irqs[i] = irq; + + host_data = devm_kzalloc(dev, sizeof(*host_data), GFP_KERNEL); + if (!host_data) { + ret = -ENOMEM; + goto fail_irq; + } + + host_data->intc = intc; + host_data->host_irq = i; + + irq_set_handler_data(irq, host_data); + irq_set_chained_handler(irq, pruss_intc_irq_handler); + } + + return 0; + +fail_irq: + while (--i >= 0) { + if (intc->irqs[i]) + irq_set_chained_handler_and_data(intc->irqs[i], NULL, + NULL); + } + + irq_domain_remove(intc->domain); + + return ret; +} + +static int pruss_intc_remove(struct platform_device *pdev) +{ + struct pruss_intc *intc = platform_get_drvdata(pdev); + u8 max_system_events = intc->soc_config->num_system_events; + unsigned int hwirq; + int i; + + for (i = 0; i < MAX_NUM_HOST_IRQS; i++) { + if (intc->irqs[i]) + irq_set_chained_handler_and_data(intc->irqs[i], NULL, + NULL); + } + + for (hwirq = 0; hwirq < max_system_events; hwirq++) + irq_dispose_mapping(irq_find_mapping(intc->domain, hwirq)); + + irq_domain_remove(intc->domain); + + return 0; +} + +static const struct pruss_intc_match_data pruss_intc_data = { + .num_system_events = 64, + .num_host_events = 10, +}; + +static const struct pruss_intc_match_data icssg_intc_data = { + .num_system_events = 160, + .num_host_events = 20, +}; + +static const struct of_device_id pruss_intc_of_match[] = { + { + .compatible = "ti,pruss-intc", + .data = &pruss_intc_data, + }, + { + .compatible = "ti,icssg-intc", + .data = &icssg_intc_data, + }, + { /* sentinel */ }, +}; +MODULE_DEVICE_TABLE(of, pruss_intc_of_match); + +static struct platform_driver pruss_intc_driver = { + .driver = { + .name = "pruss-intc", + .of_match_table = pruss_intc_of_match, + .suppress_bind_attrs = true, + }, + .probe = pruss_intc_probe, + .remove = pruss_intc_remove, +}; +module_platform_driver(pruss_intc_driver); + +MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>"); +MODULE_AUTHOR("Suman Anna <s-anna@ti.com>"); +MODULE_AUTHOR("Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>"); +MODULE_DESCRIPTION("TI PRU-ICSS INTC Driver"); +MODULE_LICENSE("GPL v2"); |