| /* |
| * Remote processor machine-specific module for DA8XX |
| * |
| * Copyright (C) 2013 Texas Instruments, Inc. |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * version 2 as published by the Free Software Foundation. |
| */ |
| |
| #include <linux/bitops.h> |
| #include <linux/clk.h> |
| #include <linux/err.h> |
| #include <linux/interrupt.h> |
| #include <linux/io.h> |
| #include <linux/irq.h> |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/platform_device.h> |
| #include <linux/remoteproc.h> |
| |
| #include <mach/clock.h> /* for davinci_clk_reset_assert/deassert() */ |
| |
| #include "remoteproc_internal.h" |
| |
| static char *da8xx_fw_name; |
| module_param(da8xx_fw_name, charp, S_IRUGO); |
| MODULE_PARM_DESC(da8xx_fw_name, |
| "Name of DSP firmware file in /lib/firmware (if not specified defaults to 'rproc-dsp-fw')"); |
| |
| /* |
| * OMAP-L138 Technical References: |
| * http://www.ti.com/product/omap-l138 |
| */ |
| #define SYSCFG_CHIPSIG0 BIT(0) |
| #define SYSCFG_CHIPSIG1 BIT(1) |
| #define SYSCFG_CHIPSIG2 BIT(2) |
| #define SYSCFG_CHIPSIG3 BIT(3) |
| #define SYSCFG_CHIPSIG4 BIT(4) |
| |
| /** |
| * struct da8xx_rproc - da8xx remote processor instance state |
| * @rproc: rproc handle |
| * @dsp_clk: placeholder for platform's DSP clk |
| * @ack_fxn: chip-specific ack function for ack'ing irq |
| * @irq_data: ack_fxn function parameter |
| * @chipsig: virt ptr to DSP interrupt registers (CHIPSIG & CHIPSIG_CLR) |
| * @bootreg: virt ptr to DSP boot address register (HOST1CFG) |
| * @irq: irq # used by this instance |
| */ |
| struct da8xx_rproc { |
| struct rproc *rproc; |
| struct clk *dsp_clk; |
| void (*ack_fxn)(struct irq_data *data); |
| struct irq_data *irq_data; |
| void __iomem *chipsig; |
| void __iomem *bootreg; |
| int irq; |
| }; |
| |
| /** |
| * handle_event() - inbound virtqueue message workqueue function |
| * |
| * This function is registered as a kernel thread and is scheduled by the |
| * kernel handler. |
| */ |
| static irqreturn_t handle_event(int irq, void *p) |
| { |
| struct rproc *rproc = (struct rproc *)p; |
| |
| /* Process incoming buffers on all our vrings */ |
| rproc_vq_interrupt(rproc, 0); |
| rproc_vq_interrupt(rproc, 1); |
| |
| return IRQ_HANDLED; |
| } |
| |
| /** |
| * da8xx_rproc_callback() - inbound virtqueue message handler |
| * |
| * This handler is invoked directly by the kernel whenever the remote |
| * core (DSP) has modified the state of a virtqueue. There is no |
| * "payload" message indicating the virtqueue index as is the case with |
| * mailbox-based implementations on OMAP4. As such, this handler "polls" |
| * each known virtqueue index for every invocation. |
| */ |
| static irqreturn_t da8xx_rproc_callback(int irq, void *p) |
| { |
| struct rproc *rproc = (struct rproc *)p; |
| struct da8xx_rproc *drproc = (struct da8xx_rproc *)rproc->priv; |
| u32 chipsig; |
| |
| chipsig = readl(drproc->chipsig); |
| if (chipsig & SYSCFG_CHIPSIG0) { |
| /* Clear interrupt level source */ |
| writel(SYSCFG_CHIPSIG0, drproc->chipsig + 4); |
| |
| /* |
| * ACK intr to AINTC. |
| * |
| * It has already been ack'ed by the kernel before calling |
| * this function, but since the ARM<->DSP interrupts in the |
| * CHIPSIG register are "level" instead of "pulse" variety, |
| * we need to ack it after taking down the level else we'll |
| * be called again immediately after returning. |
| */ |
| drproc->ack_fxn(drproc->irq_data); |
| |
| return IRQ_WAKE_THREAD; |
| } |
| |
| return IRQ_HANDLED; |
| } |
| |
| static int da8xx_rproc_start(struct rproc *rproc) |
| { |
| struct device *dev = rproc->dev.parent; |
| struct da8xx_rproc *drproc = (struct da8xx_rproc *)rproc->priv; |
| struct clk *dsp_clk = drproc->dsp_clk; |
| |
| /* hw requires the start (boot) address be on 1KB boundary */ |
| if (rproc->bootaddr & 0x3ff) { |
| dev_err(dev, "invalid boot address: must be aligned to 1KB\n"); |
| |
| return -EINVAL; |
| } |
| |
| writel(rproc->bootaddr, drproc->bootreg); |
| |
| clk_enable(dsp_clk); |
| davinci_clk_reset_deassert(dsp_clk); |
| |
| return 0; |
| } |
| |
| static int da8xx_rproc_stop(struct rproc *rproc) |
| { |
| struct da8xx_rproc *drproc = rproc->priv; |
| |
| clk_disable(drproc->dsp_clk); |
| |
| return 0; |
| } |
| |
| /* kick a virtqueue */ |
| static void da8xx_rproc_kick(struct rproc *rproc, int vqid) |
| { |
| struct da8xx_rproc *drproc = (struct da8xx_rproc *)rproc->priv; |
| |
| /* Interrupt remote proc */ |
| writel(SYSCFG_CHIPSIG2, drproc->chipsig); |
| } |
| |
| static const struct rproc_ops da8xx_rproc_ops = { |
| .start = da8xx_rproc_start, |
| .stop = da8xx_rproc_stop, |
| .kick = da8xx_rproc_kick, |
| }; |
| |
| static int da8xx_rproc_probe(struct platform_device *pdev) |
| { |
| struct device *dev = &pdev->dev; |
| struct da8xx_rproc *drproc; |
| struct rproc *rproc; |
| struct irq_data *irq_data; |
| struct resource *bootreg_res; |
| struct resource *chipsig_res; |
| struct clk *dsp_clk; |
| void __iomem *chipsig; |
| void __iomem *bootreg; |
| int irq; |
| int ret; |
| |
| irq = platform_get_irq(pdev, 0); |
| if (irq < 0) { |
| dev_err(dev, "platform_get_irq(pdev, 0) error: %d\n", irq); |
| return irq; |
| } |
| |
| irq_data = irq_get_irq_data(irq); |
| if (!irq_data) { |
| dev_err(dev, "irq_get_irq_data(%d): NULL\n", irq); |
| return -EINVAL; |
| } |
| |
| bootreg_res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| bootreg = devm_ioremap_resource(dev, bootreg_res); |
| if (IS_ERR(bootreg)) |
| return PTR_ERR(bootreg); |
| |
| chipsig_res = platform_get_resource(pdev, IORESOURCE_MEM, 1); |
| chipsig = devm_ioremap_resource(dev, chipsig_res); |
| if (IS_ERR(chipsig)) |
| return PTR_ERR(chipsig); |
| |
| dsp_clk = devm_clk_get(dev, NULL); |
| if (IS_ERR(dsp_clk)) { |
| dev_err(dev, "clk_get error: %ld\n", PTR_ERR(dsp_clk)); |
| |
| return PTR_ERR(dsp_clk); |
| } |
| |
| rproc = rproc_alloc(dev, "dsp", &da8xx_rproc_ops, da8xx_fw_name, |
| sizeof(*drproc)); |
| if (!rproc) |
| return -ENOMEM; |
| |
| drproc = rproc->priv; |
| drproc->rproc = rproc; |
| drproc->dsp_clk = dsp_clk; |
| rproc->has_iommu = false; |
| |
| platform_set_drvdata(pdev, rproc); |
| |
| /* everything the ISR needs is now setup, so hook it up */ |
| ret = devm_request_threaded_irq(dev, irq, da8xx_rproc_callback, |
| handle_event, 0, "da8xx-remoteproc", |
| rproc); |
| if (ret) { |
| dev_err(dev, "devm_request_threaded_irq error: %d\n", ret); |
| goto free_rproc; |
| } |
| |
| /* |
| * rproc_add() can end up enabling the DSP's clk with the DSP |
| * *not* in reset, but da8xx_rproc_start() needs the DSP to be |
| * held in reset at the time it is called. |
| */ |
| ret = davinci_clk_reset_assert(drproc->dsp_clk); |
| if (ret) |
| goto free_rproc; |
| |
| drproc->chipsig = chipsig; |
| drproc->bootreg = bootreg; |
| drproc->ack_fxn = irq_data->chip->irq_ack; |
| drproc->irq_data = irq_data; |
| drproc->irq = irq; |
| |
| ret = rproc_add(rproc); |
| if (ret) { |
| dev_err(dev, "rproc_add failed: %d\n", ret); |
| goto free_rproc; |
| } |
| |
| return 0; |
| |
| free_rproc: |
| rproc_free(rproc); |
| |
| return ret; |
| } |
| |
| static int da8xx_rproc_remove(struct platform_device *pdev) |
| { |
| struct rproc *rproc = platform_get_drvdata(pdev); |
| struct da8xx_rproc *drproc = (struct da8xx_rproc *)rproc->priv; |
| |
| /* |
| * It's important to place the DSP in reset before going away, |
| * since a subsequent insmod of this module may enable the DSP's |
| * clock before its program/boot-address has been loaded and |
| * before this module's probe has had a chance to reset the DSP. |
| * Without the reset, the DSP can lockup permanently when it |
| * begins executing garbage. |
| */ |
| davinci_clk_reset_assert(drproc->dsp_clk); |
| |
| /* |
| * The devm subsystem might end up releasing things before |
| * freeing the irq, thus allowing an interrupt to sneak in while |
| * the device is being removed. This should prevent that. |
| */ |
| disable_irq(drproc->irq); |
| |
| rproc_del(rproc); |
| rproc_free(rproc); |
| |
| return 0; |
| } |
| |
| static struct platform_driver da8xx_rproc_driver = { |
| .probe = da8xx_rproc_probe, |
| .remove = da8xx_rproc_remove, |
| .driver = { |
| .name = "davinci-rproc", |
| }, |
| }; |
| |
| module_platform_driver(da8xx_rproc_driver); |
| |
| MODULE_LICENSE("GPL v2"); |
| MODULE_DESCRIPTION("DA8XX Remote Processor control driver"); |