[linux-2.6-block.git] / drivers / remoteproc / da8xx_remoteproc.c

/*
 * 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");
Commit	Line	Data
13be5432 RT	1	/*
	2	* Remote processor machine-specific module for DA8XX
	3	*
	4	* Copyright (C) 2013 Texas Instruments, Inc.
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU General Public License
	8	* version 2 as published by the Free Software Foundation.
	9	*/
	10
	11	#include <linux/bitops.h>
	12	#include <linux/clk.h>
	13	#include <linux/err.h>
	14	#include <linux/interrupt.h>
	15	#include <linux/io.h>
	16	#include <linux/irq.h>
	17	#include <linux/kernel.h>
	18	#include <linux/module.h>
	19	#include <linux/platform_device.h>
	20	#include <linux/remoteproc.h>
	21
	22	#include <mach/clock.h> /* for davinci_clk_reset_assert/deassert() */
	23
	24	#include "remoteproc_internal.h"
	25
	26	static char *da8xx_fw_name;
	27	module_param(da8xx_fw_name, charp, S_IRUGO);
	28	MODULE_PARM_DESC(da8xx_fw_name,
e17aee37	29	"Name of DSP firmware file in /lib/firmware (if not specified defaults to 'rproc-dsp-fw')");
13be5432 RT	30
	31	/*
	32	* OMAP-L138 Technical References:
	33	* http://www.ti.com/product/omap-l138
	34	*/
	35	#define SYSCFG_CHIPSIG0 BIT(0)
	36	#define SYSCFG_CHIPSIG1 BIT(1)
	37	#define SYSCFG_CHIPSIG2 BIT(2)
	38	#define SYSCFG_CHIPSIG3 BIT(3)
	39	#define SYSCFG_CHIPSIG4 BIT(4)
	40
	41	/**
	42	* struct da8xx_rproc - da8xx remote processor instance state
	43	* @rproc: rproc handle
	44	* @dsp_clk: placeholder for platform's DSP clk
	45	* @ack_fxn: chip-specific ack function for ack'ing irq
	46	* @irq_data: ack_fxn function parameter
	47	* @chipsig: virt ptr to DSP interrupt registers (CHIPSIG & CHIPSIG_CLR)
	48	* @bootreg: virt ptr to DSP boot address register (HOST1CFG)
	49	* @irq: irq # used by this instance
	50	*/
	51	struct da8xx_rproc {
	52	struct rproc *rproc;
	53	struct clk *dsp_clk;
	54	void (ack_fxn)(struct irq_data data);
	55	struct irq_data *irq_data;
	56	void __iomem *chipsig;
	57	void __iomem *bootreg;
	58	int irq;
	59	};
	60
	61	/**
	62	* handle_event() - inbound virtqueue message workqueue function
	63	*
	64	* This function is registered as a kernel thread and is scheduled by the
	65	* kernel handler.
	66	*/
	67	static irqreturn_t handle_event(int irq, void *p)
	68	{
	69	struct rproc rproc = (struct rproc )p;
	70
	71	/* Process incoming buffers on all our vrings */
	72	rproc_vq_interrupt(rproc, 0);
	73	rproc_vq_interrupt(rproc, 1);
	74
	75	return IRQ_HANDLED;
	76	}
	77
	78	/**
	79	* da8xx_rproc_callback() - inbound virtqueue message handler
	80	*
	81	* This handler is invoked directly by the kernel whenever the remote
	82	* core (DSP) has modified the state of a virtqueue. There is no
	83	* "payload" message indicating the virtqueue index as is the case with
	84	* mailbox-based implementations on OMAP4. As such, this handler "polls"
	85	* each known virtqueue index for every invocation.
	86	*/
	87	static irqreturn_t da8xx_rproc_callback(int irq, void *p)
	88	{
	89	struct rproc rproc = (struct rproc )p;
	90	struct da8xx_rproc drproc = (struct da8xx_rproc )rproc->priv;
	91	u32 chipsig;
	92
	93	chipsig = readl(drproc->chipsig);
94	if (chipsig & SYSCFG_CHIPSIG0) {
95	/* Clear interrupt level source */
96	writel(SYSCFG_CHIPSIG0, drproc->chipsig + 4);
97
98	/*
99	* ACK intr to AINTC.
100	*
101	* It has already been ack'ed by the kernel before calling
102	* this function, but since the ARM<->DSP interrupts in the
103	* CHIPSIG register are "level" instead of "pulse" variety,
104	* we need to ack it after taking down the level else we'll
105	* be called again immediately after returning.
106	*/
107	drproc->ack_fxn(drproc->irq_data);
108
109	return IRQ_WAKE_THREAD;
110	}
111
112	return IRQ_HANDLED;
113	}
114
115	static int da8xx_rproc_start(struct rproc *rproc)
116	{
117	struct device *dev = rproc->dev.parent;
118	struct da8xx_rproc drproc = (struct da8xx_rproc )rproc->priv;
119	struct clk *dsp_clk = drproc->dsp_clk;
120
121	/* hw requires the start (boot) address be on 1KB boundary */
122	if (rproc->bootaddr & 0x3ff) {
123	dev_err(dev, "invalid boot address: must be aligned to 1KB\n");
124
125	return -EINVAL;
126	}
127
128	writel(rproc->bootaddr, drproc->bootreg);
129
130	clk_enable(dsp_clk);
131	davinci_clk_reset_deassert(dsp_clk);
132
133	return 0;
134	}
135
136	static int da8xx_rproc_stop(struct rproc *rproc)
137	{
138	struct da8xx_rproc *drproc = rproc->priv;
139
140	clk_disable(drproc->dsp_clk);
141
142	return 0;
143	}
144
145	/* kick a virtqueue */
146	static void da8xx_rproc_kick(struct rproc *rproc, int vqid)
147	{
148	struct da8xx_rproc drproc = (struct da8xx_rproc )rproc->priv;
149
56324d7a	150	/* Interrupt remote proc */
13be5432 RT	151	writel(SYSCFG_CHIPSIG2, drproc->chipsig);
	152	}
	153
c008fad2	154	static const struct rproc_ops da8xx_rproc_ops = {
13be5432 RT	155	.start = da8xx_rproc_start,
	156	.stop = da8xx_rproc_stop,
	157	.kick = da8xx_rproc_kick,
	158	};
	159
13be5432 RT	160	static int da8xx_rproc_probe(struct platform_device *pdev)
	161	{
	162	struct device *dev = &pdev->dev;
	163	struct da8xx_rproc *drproc;
	164	struct rproc *rproc;
	165	struct irq_data *irq_data;
	166	struct resource *bootreg_res;
	167	struct resource *chipsig_res;
	168	struct clk *dsp_clk;
	169	void __iomem *chipsig;
	170	void __iomem *bootreg;
	171	int irq;
	172	int ret;
	173
	174	irq = platform_get_irq(pdev, 0);
	175	if (irq < 0) {
	176	dev_err(dev, "platform_get_irq(pdev, 0) error: %d\n", irq);
	177	return irq;
	178	}
	179
	180	irq_data = irq_get_irq_data(irq);
	181	if (!irq_data) {
	182	dev_err(dev, "irq_get_irq_data(%d): NULL\n", irq);
	183	return -EINVAL;
	184	}
	185
	186	bootreg_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
13be5432 RT	187	bootreg = devm_ioremap_resource(dev, bootreg_res);
	188	if (IS_ERR(bootreg))
	189	return PTR_ERR(bootreg);
	190
0ddc5ec1	191	chipsig_res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
13be5432 RT	192	chipsig = devm_ioremap_resource(dev, chipsig_res);
	193	if (IS_ERR(chipsig))
	194	return PTR_ERR(chipsig);
	195
	196	dsp_clk = devm_clk_get(dev, NULL);
	197	if (IS_ERR(dsp_clk)) {
	198	dev_err(dev, "clk_get error: %ld\n", PTR_ERR(dsp_clk));
	199
	200	return PTR_ERR(dsp_clk);
	201	}
	202
	203	rproc = rproc_alloc(dev, "dsp", &da8xx_rproc_ops, da8xx_fw_name,
	204	sizeof(*drproc));
	205	if (!rproc)
	206	return -ENOMEM;
	207
	208	drproc = rproc->priv;
	209	drproc->rproc = rproc;
470ac62f	210	drproc->dsp_clk = dsp_clk;
315491e5	211	rproc->has_iommu = false;
13be5432 RT	212
	213	platform_set_drvdata(pdev, rproc);
	214
	215	/* everything the ISR needs is now setup, so hook it up */
	216	ret = devm_request_threaded_irq(dev, irq, da8xx_rproc_callback,
	217	handle_event, 0, "da8xx-remoteproc",
	218	rproc);
	219	if (ret) {
	220	dev_err(dev, "devm_request_threaded_irq error: %d\n", ret);
	221	goto free_rproc;
	222	}
	223
	224	/*
	225	* rproc_add() can end up enabling the DSP's clk with the DSP
	226	* not in reset, but da8xx_rproc_start() needs the DSP to be
	227	* held in reset at the time it is called.
	228	*/
470ac62f	229	ret = davinci_clk_reset_assert(drproc->dsp_clk);
13be5432 RT	230	if (ret)
	231	goto free_rproc;
	232
	233	drproc->chipsig = chipsig;
	234	drproc->bootreg = bootreg;
	235	drproc->ack_fxn = irq_data->chip->irq_ack;
	236	drproc->irq_data = irq_data;
	237	drproc->irq = irq;
13be5432 RT	238
	239	ret = rproc_add(rproc);
	240	if (ret) {
	241	dev_err(dev, "rproc_add failed: %d\n", ret);
	242	goto free_rproc;
	243	}
	244
	245	return 0;
	246
	247	free_rproc:
433c0e04	248	rproc_free(rproc);
13be5432 RT	249
	250	return ret;
	251	}
	252
	253	static int da8xx_rproc_remove(struct platform_device *pdev)
	254	{
13be5432 RT	255	struct rproc *rproc = platform_get_drvdata(pdev);
	256	struct da8xx_rproc drproc = (struct da8xx_rproc )rproc->priv;
	257
	258	/*
	259	* It's important to place the DSP in reset before going away,
	260	* since a subsequent insmod of this module may enable the DSP's
	261	* clock before its program/boot-address has been loaded and
	262	* before this module's probe has had a chance to reset the DSP.
	263	* Without the reset, the DSP can lockup permanently when it
	264	* begins executing garbage.
	265	*/
470ac62f	266	davinci_clk_reset_assert(drproc->dsp_clk);
13be5432 RT	267
	268	/*
	269	* The devm subsystem might end up releasing things before
	270	* freeing the irq, thus allowing an interrupt to sneak in while
	271	* the device is being removed. This should prevent that.
	272	*/
	273	disable_irq(drproc->irq);
	274
13be5432	275	rproc_del(rproc);
433c0e04	276	rproc_free(rproc);
13be5432 RT	277
	278	return 0;
	279	}
	280
	281	static struct platform_driver da8xx_rproc_driver = {
	282	.probe = da8xx_rproc_probe,
	283	.remove = da8xx_rproc_remove,
	284	.driver = {
	285	.name = "davinci-rproc",
13be5432 RT	286	},
	287	};
	288
	289	module_platform_driver(da8xx_rproc_driver);
	290
	291	MODULE_LICENSE("GPL v2");
	292	MODULE_DESCRIPTION("DA8XX Remote Processor control driver");