diff options
Diffstat (limited to 'arch/mips/kernel/rtlx-mt.c')
-rw-r--r-- | arch/mips/kernel/rtlx-mt.c | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/arch/mips/kernel/rtlx-mt.c b/arch/mips/kernel/rtlx-mt.c new file mode 100644 index 0000000000..38c6925a1b --- /dev/null +++ b/arch/mips/kernel/rtlx-mt.c @@ -0,0 +1,147 @@ +/* + * 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) 2005 MIPS Technologies, Inc. All rights reserved. + * Copyright (C) 2013 Imagination Technologies Ltd. + */ +#include <linux/device.h> +#include <linux/fs.h> +#include <linux/err.h> +#include <linux/wait.h> +#include <linux/sched.h> +#include <linux/interrupt.h> +#include <linux/irq.h> + +#include <asm/mips_mt.h> +#include <asm/vpe.h> +#include <asm/rtlx.h> + +static int major; + +static void rtlx_dispatch(void) +{ + if (read_c0_cause() & read_c0_status() & C_SW0) + do_IRQ(MIPS_CPU_IRQ_BASE + MIPS_CPU_RTLX_IRQ); +} + +/* + * Interrupt handler may be called before rtlx_init has otherwise had + * a chance to run. + */ +static irqreturn_t rtlx_interrupt(int irq, void *dev_id) +{ + unsigned int vpeflags; + unsigned long flags; + int i; + + local_irq_save(flags); + vpeflags = dvpe(); + set_c0_status(0x100 << MIPS_CPU_RTLX_IRQ); + irq_enable_hazard(); + evpe(vpeflags); + local_irq_restore(flags); + + for (i = 0; i < RTLX_CHANNELS; i++) { + wake_up(&channel_wqs[i].lx_queue); + wake_up(&channel_wqs[i].rt_queue); + } + + return IRQ_HANDLED; +} + +static int rtlx_irq_num = MIPS_CPU_IRQ_BASE + MIPS_CPU_RTLX_IRQ; + +void _interrupt_sp(void) +{ + unsigned long flags; + + local_irq_save(flags); + dvpe(); + settc(1); + write_vpe_c0_cause(read_vpe_c0_cause() | C_SW0); + evpe(EVPE_ENABLE); + local_irq_restore(flags); +} + +int __init rtlx_module_init(void) +{ + struct device *dev; + int i, err; + + if (!cpu_has_mipsmt) { + pr_warn("VPE loader: not a MIPS MT capable processor\n"); + return -ENODEV; + } + + if (aprp_cpu_index() == 0) { + pr_warn("No TCs reserved for AP/SP, not initializing RTLX.\n" + "Pass maxtcs=<n> argument as kernel argument\n"); + + return -ENODEV; + } + + major = register_chrdev(0, RTLX_MODULE_NAME, &rtlx_fops); + if (major < 0) { + pr_err("rtlx_module_init: unable to register device\n"); + return major; + } + + /* initialise the wait queues */ + for (i = 0; i < RTLX_CHANNELS; i++) { + init_waitqueue_head(&channel_wqs[i].rt_queue); + init_waitqueue_head(&channel_wqs[i].lx_queue); + atomic_set(&channel_wqs[i].in_open, 0); + mutex_init(&channel_wqs[i].mutex); + + dev = device_create(mt_class, NULL, MKDEV(major, i), NULL, + "%s%d", RTLX_MODULE_NAME, i); + if (IS_ERR(dev)) { + while (i--) + device_destroy(mt_class, MKDEV(major, i)); + + err = PTR_ERR(dev); + goto out_chrdev; + } + } + + /* set up notifiers */ + rtlx_notify.start = rtlx_starting; + rtlx_notify.stop = rtlx_stopping; + vpe_notify(aprp_cpu_index(), &rtlx_notify); + + if (cpu_has_vint) { + aprp_hook = rtlx_dispatch; + } else { + pr_err("APRP RTLX init on non-vectored-interrupt processor\n"); + err = -ENODEV; + goto out_class; + } + + err = request_irq(rtlx_irq_num, rtlx_interrupt, 0, "RTLX", rtlx); + if (err) + goto out_class; + + return 0; + +out_class: + for (i = 0; i < RTLX_CHANNELS; i++) + device_destroy(mt_class, MKDEV(major, i)); +out_chrdev: + unregister_chrdev(major, RTLX_MODULE_NAME); + + return err; +} + +void __exit rtlx_module_exit(void) +{ + int i; + + for (i = 0; i < RTLX_CHANNELS; i++) + device_destroy(mt_class, MKDEV(major, i)); + + unregister_chrdev(major, RTLX_MODULE_NAME); + + aprp_hook = NULL; +} |