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author | Robert Tivy <rtivy@ti.com> | 2013-04-09 21:20:21 (GMT) |
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committer | Ohad Ben-Cohen <ohad@wizery.com> | 2013-04-15 06:23:40 (GMT) |
commit | 13be5432d8721d89cadae105663761f45f427842 (patch) | |
tree | ee9468b54d7515f8db561079f2234e81e701a5fb /drivers/remoteproc/da8xx_remoteproc.c | |
parent | 8b4aec9ac7b59754df9c594569af9ae8f456ee07 (diff) | |
download | linux-fsl-qoriq-13be5432d8721d89cadae105663761f45f427842.tar.xz |
remoteproc/davinci: add a remoteproc driver for OMAP-L13x DSP
Adding a new remoteproc driver for OMAP-L13x DSP
Signed-off-by: Robert Tivy <rtivy@ti.com>
[removed 'EXPERIMENTAL' and fixed some indentation issues]
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Diffstat (limited to 'drivers/remoteproc/da8xx_remoteproc.c')
-rw-r--r-- | drivers/remoteproc/da8xx_remoteproc.c | 324 |
1 files changed, 324 insertions, 0 deletions
diff --git a/drivers/remoteproc/da8xx_remoteproc.c b/drivers/remoteproc/da8xx_remoteproc.c new file mode 100644 index 0000000..9b2e60a --- /dev/null +++ b/drivers/remoteproc/da8xx_remoteproc.c @@ -0,0 +1,324 @@ +/* + * 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, + "\n\t\tName 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; + + /* Interupt remote proc */ + writel(SYSCFG_CHIPSIG2, drproc->chipsig); +} + +static struct rproc_ops da8xx_rproc_ops = { + .start = da8xx_rproc_start, + .stop = da8xx_rproc_stop, + .kick = da8xx_rproc_kick, +}; + +static int reset_assert(struct device *dev) +{ + struct clk *dsp_clk; + + dsp_clk = clk_get(dev, NULL); + if (IS_ERR(dsp_clk)) { + dev_err(dev, "clk_get error: %ld\n", PTR_ERR(dsp_clk)); + return PTR_RET(dsp_clk); + } + + davinci_clk_reset_assert(dsp_clk); + clk_put(dsp_clk); + + return 0; +} + +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); + if (!bootreg_res) { + dev_err(dev, + "platform_get_resource(IORESOURCE_MEM, 0): NULL\n"); + return -EADDRNOTAVAIL; + } + + chipsig_res = platform_get_resource(pdev, IORESOURCE_MEM, 1); + if (!chipsig_res) { + dev_err(dev, + "platform_get_resource(IORESOURCE_MEM, 1): NULL\n"); + return -EADDRNOTAVAIL; + } + + bootreg = devm_ioremap_resource(dev, bootreg_res); + if (IS_ERR(bootreg)) + return PTR_ERR(bootreg); + + 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; + + 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 = reset_assert(dev); + 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; + drproc->dsp_clk = dsp_clk; + + ret = rproc_add(rproc); + if (ret) { + dev_err(dev, "rproc_add failed: %d\n", ret); + goto free_rproc; + } + + return 0; + +free_rproc: + rproc_put(rproc); + + return ret; +} + +static int da8xx_rproc_remove(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + 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. + */ + reset_assert(dev); + + /* + * 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); + + devm_clk_put(dev, drproc->dsp_clk); + + rproc_del(rproc); + rproc_put(rproc); + + return 0; +} + +static struct platform_driver da8xx_rproc_driver = { + .probe = da8xx_rproc_probe, + .remove = da8xx_rproc_remove, + .driver = { + .name = "davinci-rproc", + .owner = THIS_MODULE, + }, +}; + +module_platform_driver(da8xx_rproc_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("DA8XX Remote Processor control driver"); |