drivers/remoteproc/keystone_remoteproc.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  * TI Keystone DSP remoteproc driver
0004  *
0005  * Copyright (C) 2015-2017 Texas Instruments Incorporated - http://www.ti.com/
0006  */
0007
0008 #include <linux/module.h>
0009 #include <linux/slab.h>
0010 #include <linux/io.h>
0011 #include <linux/interrupt.h>
0012 #include <linux/platform_device.h>
0013 #include <linux/pm_runtime.h>
0014 #include <linux/workqueue.h>
0015 #include <linux/of_address.h>
0016 #include <linux/of_reserved_mem.h>
0017 #include <linux/of_gpio.h>
0018 #include <linux/regmap.h>
0019 #include <linux/mfd/syscon.h>
0020 #include <linux/remoteproc.h>
0021 #include <linux/reset.h>
0022
0023 #include "remoteproc_internal.h"
0024
0025 #define KEYSTONE_RPROC_LOCAL_ADDRESS_MASK   (SZ_16M - 1)
0026
0027 /**
0028  * struct keystone_rproc_mem - internal memory structure
0029  * @cpu_addr: MPU virtual address of the memory region
0030  * @bus_addr: Bus address used to access the memory region
0031  * @dev_addr: Device address of the memory region from DSP view
0032  * @size: Size of the memory region
0033  */
0034 struct keystone_rproc_mem {
0035     void __iomem *cpu_addr;
0036     phys_addr_t bus_addr;
0037     u32 dev_addr;
0038     size_t size;
0039 };
0040
0041 /**
0042  * struct keystone_rproc - keystone remote processor driver structure
0043  * @dev: cached device pointer
0044  * @rproc: remoteproc device handle
0045  * @mem: internal memory regions data
0046  * @num_mems: number of internal memory regions
0047  * @dev_ctrl: device control regmap handle
0048  * @reset: reset control handle
0049  * @boot_offset: boot register offset in @dev_ctrl regmap
0050  * @irq_ring: irq entry for vring
0051  * @irq_fault: irq entry for exception
0052  * @kick_gpio: gpio used for virtio kicks
0053  * @workqueue: workqueue for processing virtio interrupts
0054  */
0055 struct keystone_rproc {
0056     struct device *dev;
0057     struct rproc *rproc;
0058     struct keystone_rproc_mem *mem;
0059     int num_mems;
0060     struct regmap *dev_ctrl;
0061     struct reset_control *reset;
0062     u32 boot_offset;
0063     int irq_ring;
0064     int irq_fault;
0065     int kick_gpio;
0066     struct work_struct workqueue;
0067 };
0068
0069 /* Put the DSP processor into reset */
0070 static void keystone_rproc_dsp_reset(struct keystone_rproc *ksproc)
0071 {
0072     reset_control_assert(ksproc->reset);
0073 }
0074
0075 /* Configure the boot address and boot the DSP processor */
0076 static int keystone_rproc_dsp_boot(struct keystone_rproc *ksproc, u32 boot_addr)
0077 {
0078     int ret;
0079
0080     if (boot_addr & (SZ_1K - 1)) {
0081         dev_err(ksproc->dev, "invalid boot address 0x%x, must be aligned on a 1KB boundary\n",
0082             boot_addr);
0083         return -EINVAL;
0084     }
0085
0086     ret = regmap_write(ksproc->dev_ctrl, ksproc->boot_offset, boot_addr);
0087     if (ret) {
0088         dev_err(ksproc->dev, "regmap_write of boot address failed, status = %d\n",
0089             ret);
0090         return ret;
0091     }
0092
0093     reset_control_deassert(ksproc->reset);
0094
0095     return 0;
0096 }
0097
0098 /*
0099  * Process the remoteproc exceptions
0100  *
0101  * The exception reporting on Keystone DSP remote processors is very simple
0102  * compared to the equivalent processors on the OMAP family, it is notified
0103  * through a software-designed specific interrupt source in the IPC interrupt
0104  * generation register.
0105  *
0106  * This function just invokes the rproc_report_crash to report the exception
0107  * to the remoteproc driver core, to trigger a recovery.
0108  */
0109 static irqreturn_t keystone_rproc_exception_interrupt(int irq, void *dev_id)
0110 {
0111     struct keystone_rproc *ksproc = dev_id;
0112
0113     rproc_report_crash(ksproc->rproc, RPROC_FATAL_ERROR);
0114
0115     return IRQ_HANDLED;
0116 }
0117
0118 /*
0119  * Main virtqueue message workqueue function
0120  *
0121  * This function is executed upon scheduling of the keystone remoteproc
0122  * driver's workqueue. The workqueue is scheduled by the vring ISR handler.
0123  *
0124  * There is no payload message indicating the virtqueue index as is the
0125  * case with mailbox-based implementations on OMAP family. As such, this
0126  * handler processes both the Tx and Rx virtqueue indices on every invocation.
0127  * The rproc_vq_interrupt function can detect if there are new unprocessed
0128  * messages or not (returns IRQ_NONE vs IRQ_HANDLED), but there is no need
0129  * to check for these return values. The index 0 triggering will process all
0130  * pending Rx buffers, and the index 1 triggering will process all newly
0131  * available Tx buffers and will wakeup any potentially blocked senders.
0132  *
0133  * NOTE:
0134  * 1. A payload could be added by using some of the source bits in the
0135  *    IPC interrupt generation registers, but this would need additional
0136  *    changes to the overall IPC stack, and currently there are no benefits
0137  *    of adapting that approach.
0138  * 2. The current logic is based on an inherent design assumption of supporting
0139  *    only 2 vrings, but this can be changed if needed.
0140  */
0141 static void handle_event(struct work_struct *work)
0142 {
0143     struct keystone_rproc *ksproc =
0144         container_of(work, struct keystone_rproc, workqueue);
0145
0146     rproc_vq_interrupt(ksproc->rproc, 0);
0147     rproc_vq_interrupt(ksproc->rproc, 1);
0148 }
0149
0150 /*
0151  * Interrupt handler for processing vring kicks from remote processor
0152  */
0153 static irqreturn_t keystone_rproc_vring_interrupt(int irq, void *dev_id)
0154 {
0155     struct keystone_rproc *ksproc = dev_id;
0156
0157     schedule_work(&ksproc->workqueue);
0158
0159     return IRQ_HANDLED;
0160 }
0161
0162 /*
0163  * Power up the DSP remote processor.
0164  *
0165  * This function will be invoked only after the firmware for this rproc
0166  * was loaded, parsed successfully, and all of its resource requirements
0167  * were met.
0168  */
0169 static int keystone_rproc_start(struct rproc *rproc)
0170 {
0171     struct keystone_rproc *ksproc = rproc->priv;
0172     int ret;
0173
0174     INIT_WORK(&ksproc->workqueue, handle_event);
0175
0176     ret = request_irq(ksproc->irq_ring, keystone_rproc_vring_interrupt, 0,
0177               dev_name(ksproc->dev), ksproc);
0178     if (ret) {
0179         dev_err(ksproc->dev, "failed to enable vring interrupt, ret = %d\n",
0180             ret);
0181         goto out;
0182     }
0183
0184     ret = request_irq(ksproc->irq_fault, keystone_rproc_exception_interrupt,
0185               0, dev_name(ksproc->dev), ksproc);
0186     if (ret) {
0187         dev_err(ksproc->dev, "failed to enable exception interrupt, ret = %d\n",
0188             ret);
0189         goto free_vring_irq;
0190     }
0191
0192     ret = keystone_rproc_dsp_boot(ksproc, rproc->bootaddr);
0193     if (ret)
0194         goto free_exc_irq;
0195
0196     return 0;
0197
0198 free_exc_irq:
0199     free_irq(ksproc->irq_fault, ksproc);
0200 free_vring_irq:
0201     free_irq(ksproc->irq_ring, ksproc);
0202     flush_work(&ksproc->workqueue);
0203 out:
0204     return ret;
0205 }
0206
0207 /*
0208  * Stop the DSP remote processor.
0209  *
0210  * This function puts the DSP processor into reset, and finishes processing
0211  * of any pending messages.
0212  */
0213 static int keystone_rproc_stop(struct rproc *rproc)
0214 {
0215     struct keystone_rproc *ksproc = rproc->priv;
0216
0217     keystone_rproc_dsp_reset(ksproc);
0218     free_irq(ksproc->irq_fault, ksproc);
0219     free_irq(ksproc->irq_ring, ksproc);
0220     flush_work(&ksproc->workqueue);
0221
0222     return 0;
0223 }
0224
0225 /*
0226  * Kick the remote processor to notify about pending unprocessed messages.
0227  * The vqid usage is not used and is inconsequential, as the kick is performed
0228  * through a simulated GPIO (a bit in an IPC interrupt-triggering register),
0229  * the remote processor is expected to process both its Tx and Rx virtqueues.
0230  */
0231 static void keystone_rproc_kick(struct rproc *rproc, int vqid)
0232 {
0233     struct keystone_rproc *ksproc = rproc->priv;
0234
0235     if (WARN_ON(ksproc->kick_gpio < 0))
0236         return;
0237
0238     gpio_set_value(ksproc->kick_gpio, 1);
0239 }
0240
0241 /*
0242  * Custom function to translate a DSP device address (internal RAMs only) to a
0243  * kernel virtual address.  The DSPs can access their RAMs at either an internal
0244  * address visible only from a DSP, or at the SoC-level bus address. Both these
0245  * addresses need to be looked through for translation. The translated addresses
0246  * can be used either by the remoteproc core for loading (when using kernel
0247  * remoteproc loader), or by any rpmsg bus drivers.
0248  */
0249 static void *keystone_rproc_da_to_va(struct rproc *rproc, u64 da, size_t len, bool *is_iomem)
0250 {
0251     struct keystone_rproc *ksproc = rproc->priv;
0252     void __iomem *va = NULL;
0253     phys_addr_t bus_addr;
0254     u32 dev_addr, offset;
0255     size_t size;
0256     int i;
0257
0258     if (len == 0)
0259         return NULL;
0260
0261     for (i = 0; i < ksproc->num_mems; i++) {
0262         bus_addr = ksproc->mem[i].bus_addr;
0263         dev_addr = ksproc->mem[i].dev_addr;
0264         size = ksproc->mem[i].size;
0265
0266         if (da < KEYSTONE_RPROC_LOCAL_ADDRESS_MASK) {
0267             /* handle DSP-view addresses */
0268             if ((da >= dev_addr) &&
0269                 ((da + len) <= (dev_addr + size))) {
0270                 offset = da - dev_addr;
0271                 va = ksproc->mem[i].cpu_addr + offset;
0272                 break;
0273             }
0274         } else {
0275             /* handle SoC-view addresses */
0276             if ((da >= bus_addr) &&
0277                 (da + len) <= (bus_addr + size)) {
0278                 offset = da - bus_addr;
0279                 va = ksproc->mem[i].cpu_addr + offset;
0280                 break;
0281             }
0282         }
0283     }
0284
0285     return (__force void *)va;
0286 }
0287
0288 static const struct rproc_ops keystone_rproc_ops = {
0289     .start      = keystone_rproc_start,
0290     .stop       = keystone_rproc_stop,
0291     .kick       = keystone_rproc_kick,
0292     .da_to_va   = keystone_rproc_da_to_va,
0293 };
0294
0295 static int keystone_rproc_of_get_memories(struct platform_device *pdev,
0296                       struct keystone_rproc *ksproc)
0297 {
0298     static const char * const mem_names[] = {"l2sram", "l1pram", "l1dram"};
0299     struct device *dev = &pdev->dev;
0300     struct resource *res;
0301     int num_mems = 0;
0302     int i;
0303
0304     num_mems = ARRAY_SIZE(mem_names);
0305     ksproc->mem = devm_kcalloc(ksproc->dev, num_mems,
0306                    sizeof(*ksproc->mem), GFP_KERNEL);
0307     if (!ksproc->mem)
0308         return -ENOMEM;
0309
0310     for (i = 0; i < num_mems; i++) {
0311         res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
0312                            mem_names[i]);
0313         ksproc->mem[i].cpu_addr = devm_ioremap_resource(dev, res);
0314         if (IS_ERR(ksproc->mem[i].cpu_addr)) {
0315             dev_err(dev, "failed to parse and map %s memory\n",
0316                 mem_names[i]);
0317             return PTR_ERR(ksproc->mem[i].cpu_addr);
0318         }
0319         ksproc->mem[i].bus_addr = res->start;
0320         ksproc->mem[i].dev_addr =
0321                 res->start & KEYSTONE_RPROC_LOCAL_ADDRESS_MASK;
0322         ksproc->mem[i].size = resource_size(res);
0323
0324         /* zero out memories to start in a pristine state */
0325         memset((__force void *)ksproc->mem[i].cpu_addr, 0,
0326                ksproc->mem[i].size);
0327     }
0328     ksproc->num_mems = num_mems;
0329
0330     return 0;
0331 }
0332
0333 static int keystone_rproc_of_get_dev_syscon(struct platform_device *pdev,
0334                         struct keystone_rproc *ksproc)
0335 {
0336     struct device_node *np = pdev->dev.of_node;
0337     struct device *dev = &pdev->dev;
0338     int ret;
0339
0340     if (!of_property_read_bool(np, "ti,syscon-dev")) {
0341         dev_err(dev, "ti,syscon-dev property is absent\n");
0342         return -EINVAL;
0343     }
0344
0345     ksproc->dev_ctrl =
0346         syscon_regmap_lookup_by_phandle(np, "ti,syscon-dev");
0347     if (IS_ERR(ksproc->dev_ctrl)) {
0348         ret = PTR_ERR(ksproc->dev_ctrl);
0349         return ret;
0350     }
0351
0352     if (of_property_read_u32_index(np, "ti,syscon-dev", 1,
0353                        &ksproc->boot_offset)) {
0354         dev_err(dev, "couldn't read the boot register offset\n");
0355         return -EINVAL;
0356     }
0357
0358     return 0;
0359 }
0360
0361 static int keystone_rproc_probe(struct platform_device *pdev)
0362 {
0363     struct device *dev = &pdev->dev;
0364     struct device_node *np = dev->of_node;
0365     struct keystone_rproc *ksproc;
0366     struct rproc *rproc;
0367     int dsp_id;
0368     char *fw_name = NULL;
0369     char *template = "keystone-dsp%d-fw";
0370     int name_len = 0;
0371     int ret = 0;
0372
0373     if (!np) {
0374         dev_err(dev, "only DT-based devices are supported\n");
0375         return -ENODEV;
0376     }
0377
0378     dsp_id = of_alias_get_id(np, "rproc");
0379     if (dsp_id < 0) {
0380         dev_warn(dev, "device does not have an alias id\n");
0381         return dsp_id;
0382     }
0383
0384     /* construct a custom default fw name - subject to change in future */
0385     name_len = strlen(template); /* assuming a single digit alias */
0386     fw_name = devm_kzalloc(dev, name_len, GFP_KERNEL);
0387     if (!fw_name)
0388         return -ENOMEM;
0389     snprintf(fw_name, name_len, template, dsp_id);
0390
0391     rproc = rproc_alloc(dev, dev_name(dev), &keystone_rproc_ops, fw_name,
0392                 sizeof(*ksproc));
0393     if (!rproc)
0394         return -ENOMEM;
0395
0396     rproc->has_iommu = false;
0397     ksproc = rproc->priv;
0398     ksproc->rproc = rproc;
0399     ksproc->dev = dev;
0400
0401     ret = keystone_rproc_of_get_dev_syscon(pdev, ksproc);
0402     if (ret)
0403         goto free_rproc;
0404
0405     ksproc->reset = devm_reset_control_get_exclusive(dev, NULL);
0406     if (IS_ERR(ksproc->reset)) {
0407         ret = PTR_ERR(ksproc->reset);
0408         goto free_rproc;
0409     }
0410
0411     /* enable clock for accessing DSP internal memories */
0412     pm_runtime_enable(dev);
0413     ret = pm_runtime_resume_and_get(dev);
0414     if (ret < 0) {
0415         dev_err(dev, "failed to enable clock, status = %d\n", ret);
0416         goto disable_rpm;
0417     }
0418
0419     ret = keystone_rproc_of_get_memories(pdev, ksproc);
0420     if (ret)
0421         goto disable_clk;
0422
0423     ksproc->irq_ring = platform_get_irq_byname(pdev, "vring");
0424     if (ksproc->irq_ring < 0) {
0425         ret = ksproc->irq_ring;
0426         goto disable_clk;
0427     }
0428
0429     ksproc->irq_fault = platform_get_irq_byname(pdev, "exception");
0430     if (ksproc->irq_fault < 0) {
0431         ret = ksproc->irq_fault;
0432         goto disable_clk;
0433     }
0434
0435     ksproc->kick_gpio = of_get_named_gpio_flags(np, "kick-gpios", 0, NULL);
0436     if (ksproc->kick_gpio < 0) {
0437         ret = ksproc->kick_gpio;
0438         dev_err(dev, "failed to get gpio for virtio kicks, status = %d\n",
0439             ret);
0440         goto disable_clk;
0441     }
0442
0443     if (of_reserved_mem_device_init(dev))
0444         dev_warn(dev, "device does not have specific CMA pool\n");
0445
0446     /* ensure the DSP is in reset before loading firmware */
0447     ret = reset_control_status(ksproc->reset);
0448     if (ret < 0) {
0449         dev_err(dev, "failed to get reset status, status = %d\n", ret);
0450         goto release_mem;
0451     } else if (ret == 0) {
0452         WARN(1, "device is not in reset\n");
0453         keystone_rproc_dsp_reset(ksproc);
0454     }
0455
0456     ret = rproc_add(rproc);
0457     if (ret) {
0458         dev_err(dev, "failed to add register device with remoteproc core, status = %d\n",
0459             ret);
0460         goto release_mem;
0461     }
0462
0463     platform_set_drvdata(pdev, ksproc);
0464
0465     return 0;
0466
0467 release_mem:
0468     of_reserved_mem_device_release(dev);
0469 disable_clk:
0470     pm_runtime_put_sync(dev);
0471 disable_rpm:
0472     pm_runtime_disable(dev);
0473 free_rproc:
0474     rproc_free(rproc);
0475     return ret;
0476 }
0477
0478 static int keystone_rproc_remove(struct platform_device *pdev)
0479 {
0480     struct keystone_rproc *ksproc = platform_get_drvdata(pdev);
0481
0482     rproc_del(ksproc->rproc);
0483     pm_runtime_put_sync(&pdev->dev);
0484     pm_runtime_disable(&pdev->dev);
0485     rproc_free(ksproc->rproc);
0486     of_reserved_mem_device_release(&pdev->dev);
0487
0488     return 0;
0489 }
0490
0491 static const struct of_device_id keystone_rproc_of_match[] = {
0492     { .compatible = "ti,k2hk-dsp", },
0493     { .compatible = "ti,k2l-dsp", },
0494     { .compatible = "ti,k2e-dsp", },
0495     { .compatible = "ti,k2g-dsp", },
0496     { /* sentinel */ },
0497 };
0498 MODULE_DEVICE_TABLE(of, keystone_rproc_of_match);
0499
0500 static struct platform_driver keystone_rproc_driver = {
0501     .probe  = keystone_rproc_probe,
0502     .remove = keystone_rproc_remove,
0503     .driver = {
0504         .name = "keystone-rproc",
0505         .of_match_table = keystone_rproc_of_match,
0506     },
0507 };
0508
0509 module_platform_driver(keystone_rproc_driver);
0510
0511 MODULE_AUTHOR("Suman Anna <s-anna@ti.com>");
0512 MODULE_LICENSE("GPL v2");
0513 MODULE_DESCRIPTION("TI Keystone DSP Remoteproc driver");