drivers/remoteproc/da8xx_remoteproc.c

   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/reset.h>
  14 #include <linux/err.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/io.h>
  17 #include <linux/irq.h>
  18 #include <linux/kernel.h>
  19 #include <linux/module.h>
  20 #include <linux/of_reserved_mem.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/remoteproc.h>
  23
  24 #include "remoteproc_internal.h"
  25
  26 static char *da8xx_fw_name;
  27 module_param(da8xx_fw_name, charp, 0444);
  28 MODULE_PARM_DESC(da8xx_fw_name,
  29                  "Name of DSP firmware file in /lib/firmware (if not specified defaults to 'rproc-dsp-fw')");
  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 #define DA8XX_RPROC_LOCAL_ADDRESS_MASK  (SZ_16M - 1)
  42
  43 /**
  44  * struct da8xx_rproc_mem - internal memory structure
  45  * @cpu_addr: MPU virtual address of the memory region
  46  * @bus_addr: Bus address used to access the memory region
  47  * @dev_addr: Device address of the memory region from DSP view
  48  * @size: Size of the memory region
  49  */
  50 struct da8xx_rproc_mem {
  51         void __iomem *cpu_addr;
  52         phys_addr_t bus_addr;
  53         u32 dev_addr;
  54         size_t size;
  55 };
  56
  57 /**
  58  * struct da8xx_rproc - da8xx remote processor instance state
  59  * @rproc: rproc handle
  60  * @mem: internal memory regions data
  61  * @num_mems: number of internal memory regions
  62  * @dsp_clk: placeholder for platform's DSP clk
  63  * @ack_fxn: chip-specific ack function for ack'ing irq
  64  * @irq_data: ack_fxn function parameter
  65  * @chipsig: virt ptr to DSP interrupt registers (CHIPSIG & CHIPSIG_CLR)
  66  * @bootreg: virt ptr to DSP boot address register (HOST1CFG)
  67  * @irq: irq # used by this instance
  68  */
  69 struct da8xx_rproc {
  70         struct rproc *rproc;
  71         struct da8xx_rproc_mem *mem;
  72         int num_mems;
  73         struct clk *dsp_clk;
  74         struct reset_control *dsp_reset;
  75         void (*ack_fxn)(struct irq_data *data);
  76         struct irq_data *irq_data;
  77         void __iomem *chipsig;
  78         void __iomem *bootreg;
  79         int irq;
  80 };
  81
  82 /**
  83  * handle_event() - inbound virtqueue message workqueue function
  84  *
  85  * This function is registered as a kernel thread and is scheduled by the
  86  * kernel handler.
  87  */
  88 static irqreturn_t handle_event(int irq, void *p)
  89 {
  90         struct rproc *rproc = (struct rproc *)p;
  91
  92         /* Process incoming buffers on all our vrings */
  93         rproc_vq_interrupt(rproc, 0);
  94         rproc_vq_interrupt(rproc, 1);
  95
  96         return IRQ_HANDLED;
  97 }
  98
  99 /**
 100  * da8xx_rproc_callback() - inbound virtqueue message handler
 101  *
 102  * This handler is invoked directly by the kernel whenever the remote
 103  * core (DSP) has modified the state of a virtqueue.  There is no
 104  * "payload" message indicating the virtqueue index as is the case with
 105  * mailbox-based implementations on OMAP4.  As such, this handler "polls"
 106  * each known virtqueue index for every invocation.
 107  */
 108 static irqreturn_t da8xx_rproc_callback(int irq, void *p)
 109 {
 110         struct rproc *rproc = (struct rproc *)p;
 111         struct da8xx_rproc *drproc = (struct da8xx_rproc *)rproc->priv;
 112         u32 chipsig;
 113
 114         chipsig = readl(drproc->chipsig);
 115         if (chipsig & SYSCFG_CHIPSIG0) {
 116                 /* Clear interrupt level source */
 117                 writel(SYSCFG_CHIPSIG0, drproc->chipsig + 4);
 118
 119                 /*
 120                  * ACK intr to AINTC.
 121                  *
 122                  * It has already been ack'ed by the kernel before calling
 123                  * this function, but since the ARM<->DSP interrupts in the
 124                  * CHIPSIG register are "level" instead of "pulse" variety,
 125                  * we need to ack it after taking down the level else we'll
 126                  * be called again immediately after returning.
 127                  */
 128                 drproc->ack_fxn(drproc->irq_data);
 129
 130                 return IRQ_WAKE_THREAD;
 131         }
 132
 133         return IRQ_HANDLED;
 134 }
 135
 136 static int da8xx_rproc_start(struct rproc *rproc)
 137 {
 138         struct device *dev = rproc->dev.parent;
 139         struct da8xx_rproc *drproc = (struct da8xx_rproc *)rproc->priv;
 140         struct clk *dsp_clk = drproc->dsp_clk;
 141         struct reset_control *dsp_reset = drproc->dsp_reset;
 142         int ret;
 143
 144         /* hw requires the start (boot) address be on 1KB boundary */
 145         if (rproc->bootaddr & 0x3ff) {
 146                 dev_err(dev, "invalid boot address: must be aligned to 1KB\n");
 147
 148                 return -EINVAL;
 149         }
 150
 151         writel(rproc->bootaddr, drproc->bootreg);
 152
 153         ret = clk_prepare_enable(dsp_clk);
 154         if (ret) {
 155                 dev_err(dev, "clk_prepare_enable() failed: %d\n", ret);
 156                 return ret;
 157         }
 158
 159         ret = reset_control_deassert(dsp_reset);
 160         if (ret) {
 161                 dev_err(dev, "reset_control_deassert() failed: %d\n", ret);
 162                 clk_disable_unprepare(dsp_clk);
 163                 return ret;
 164         }
 165
 166         return 0;
 167 }
 168
 169 static int da8xx_rproc_stop(struct rproc *rproc)
 170 {
 171         struct da8xx_rproc *drproc = rproc->priv;
 172         struct device *dev = rproc->dev.parent;
 173         int ret;
 174
 175         ret = reset_control_assert(drproc->dsp_reset);
 176         if (ret) {
 177                 dev_err(dev, "reset_control_assert() failed: %d\n", ret);
 178                 return ret;
 179         }
 180
 181         clk_disable_unprepare(drproc->dsp_clk);
 182
 183         return 0;
 184 }
 185
 186 /* kick a virtqueue */
 187 static void da8xx_rproc_kick(struct rproc *rproc, int vqid)
 188 {
 189         struct da8xx_rproc *drproc = (struct da8xx_rproc *)rproc->priv;
 190
 191         /* Interrupt remote proc */
 192         writel(SYSCFG_CHIPSIG2, drproc->chipsig);
 193 }
 194
 195 static const struct rproc_ops da8xx_rproc_ops = {
 196         .start = da8xx_rproc_start,
 197         .stop = da8xx_rproc_stop,
 198         .kick = da8xx_rproc_kick,
 199 };
 200
 201 static int da8xx_rproc_get_internal_memories(struct platform_device *pdev,
 202                                              struct da8xx_rproc *drproc)
 203 {
 204         static const char * const mem_names[] = {"l2sram", "l1pram", "l1dram"};
 205         int num_mems = ARRAY_SIZE(mem_names);
 206         struct device *dev = &pdev->dev;
 207         struct resource *res;
 208         int i;
 209
 210         drproc->mem = devm_kcalloc(dev, num_mems, sizeof(*drproc->mem),
 211                                    GFP_KERNEL);
 212         if (!drproc->mem)
 213                 return -ENOMEM;
 214
 215         for (i = 0; i < num_mems; i++) {
 216                 res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
 217                                                    mem_names[i]);
 218                 drproc->mem[i].cpu_addr = devm_ioremap_resource(dev, res);
 219                 if (IS_ERR(drproc->mem[i].cpu_addr)) {
 220                         dev_err(dev, "failed to parse and map %s memory\n",
 221                                 mem_names[i]);
 222                         return PTR_ERR(drproc->mem[i].cpu_addr);
 223                 }
 224                 drproc->mem[i].bus_addr = res->start;
 225                 drproc->mem[i].dev_addr =
 226                                 res->start & DA8XX_RPROC_LOCAL_ADDRESS_MASK;
 227                 drproc->mem[i].size = resource_size(res);
 228
 229                 dev_dbg(dev, "memory %8s: bus addr %pa size 0x%zx va %p da 0x%x\n",
 230                         mem_names[i], &drproc->mem[i].bus_addr,
 231                         drproc->mem[i].size, drproc->mem[i].cpu_addr,
 232                         drproc->mem[i].dev_addr);
 233         }
 234         drproc->num_mems = num_mems;
 235
 236         return 0;
 237 }
 238
 239 static int da8xx_rproc_probe(struct platform_device *pdev)
 240 {
 241         struct device *dev = &pdev->dev;
 242         struct da8xx_rproc *drproc;
 243         struct rproc *rproc;
 244         struct irq_data *irq_data;
 245         struct resource *bootreg_res;
 246         struct resource *chipsig_res;
 247         struct clk *dsp_clk;
 248         struct reset_control *dsp_reset;
 249         void __iomem *chipsig;
 250         void __iomem *bootreg;
 251         int irq;
 252         int ret;
 253
 254         irq = platform_get_irq(pdev, 0);
 255         if (irq < 0) {
 256                 dev_err(dev, "platform_get_irq(pdev, 0) error: %d\n", irq);
 257                 return irq;
 258         }
 259
 260         irq_data = irq_get_irq_data(irq);
 261         if (!irq_data) {
 262                 dev_err(dev, "irq_get_irq_data(%d): NULL\n", irq);
 263                 return -EINVAL;
 264         }
 265
 266         bootreg_res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
 267                                                    "host1cfg");
 268         bootreg = devm_ioremap_resource(dev, bootreg_res);
 269         if (IS_ERR(bootreg))
 270                 return PTR_ERR(bootreg);
 271
 272         chipsig_res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
 273                                                    "chipsig");
 274         chipsig = devm_ioremap_resource(dev, chipsig_res);
 275         if (IS_ERR(chipsig))
 276                 return PTR_ERR(chipsig);
 277
 278         dsp_clk = devm_clk_get(dev, NULL);
 279         if (IS_ERR(dsp_clk)) {
 280                 dev_err(dev, "clk_get error: %ld\n", PTR_ERR(dsp_clk));
 281
 282                 return PTR_ERR(dsp_clk);
 283         }
 284
 285         dsp_reset = devm_reset_control_get_exclusive(dev, NULL);
 286         if (IS_ERR(dsp_reset)) {
 287                 if (PTR_ERR(dsp_reset) != -EPROBE_DEFER)
 288                         dev_err(dev, "unable to get reset control: %ld\n",
 289                                 PTR_ERR(dsp_reset));
 290
 291                 return PTR_ERR(dsp_reset);
 292         }
 293
 294         if (dev->of_node) {
 295                 ret = of_reserved_mem_device_init(dev);
 296                 if (ret) {
 297                         dev_err(dev, "device does not have specific CMA pool: %d\n",
 298                                 ret);
 299                         return ret;
 300                 }
 301         }
 302
 303         rproc = rproc_alloc(dev, "dsp", &da8xx_rproc_ops, da8xx_fw_name,
 304                 sizeof(*drproc));
 305         if (!rproc) {
 306                 ret = -ENOMEM;
 307                 goto free_mem;
 308         }
 309
 310         /* error recovery is not supported at present */
 311         rproc->recovery_disabled = true;
 312
 313         drproc = rproc->priv;
 314         drproc->rproc = rproc;
 315         drproc->dsp_clk = dsp_clk;
 316         drproc->dsp_reset = dsp_reset;
 317         rproc->has_iommu = false;
 318
 319         ret = da8xx_rproc_get_internal_memories(pdev, drproc);
 320         if (ret)
 321                 goto free_rproc;
 322
 323         platform_set_drvdata(pdev, rproc);
 324
 325         /* everything the ISR needs is now setup, so hook it up */
 326         ret = devm_request_threaded_irq(dev, irq, da8xx_rproc_callback,
 327                                         handle_event, 0, "da8xx-remoteproc",
 328                                         rproc);
 329         if (ret) {
 330                 dev_err(dev, "devm_request_threaded_irq error: %d\n", ret);
 331                 goto free_rproc;
 332         }
 333
 334         /*
 335          * rproc_add() can end up enabling the DSP's clk with the DSP
 336          * *not* in reset, but da8xx_rproc_start() needs the DSP to be
 337          * held in reset at the time it is called.
 338          */
 339         ret = reset_control_assert(dsp_reset);
 340         if (ret)
 341                 goto free_rproc;
 342
 343         drproc->chipsig = chipsig;
 344         drproc->bootreg = bootreg;
 345         drproc->ack_fxn = irq_data->chip->irq_ack;
 346         drproc->irq_data = irq_data;
 347         drproc->irq = irq;
 348
 349         ret = rproc_add(rproc);
 350         if (ret) {
 351                 dev_err(dev, "rproc_add failed: %d\n", ret);
 352                 goto free_rproc;
 353         }
 354
 355         return 0;
 356
 357 free_rproc:
 358         rproc_free(rproc);
 359 free_mem:
 360         if (dev->of_node)
 361                 of_reserved_mem_device_release(dev);
 362         return ret;
 363 }
 364
 365 static int da8xx_rproc_remove(struct platform_device *pdev)
 366 {
 367         struct rproc *rproc = platform_get_drvdata(pdev);
 368         struct da8xx_rproc *drproc = (struct da8xx_rproc *)rproc->priv;
 369         struct device *dev = &pdev->dev;
 370
 371         /*
 372          * The devm subsystem might end up releasing things before
 373          * freeing the irq, thus allowing an interrupt to sneak in while
 374          * the device is being removed.  This should prevent that.
 375          */
 376         disable_irq(drproc->irq);
 377
 378         rproc_del(rproc);
 379         rproc_free(rproc);
 380         if (dev->of_node)
 381                 of_reserved_mem_device_release(dev);
 382
 383         return 0;
 384 }
 385
 386 static const struct of_device_id davinci_rproc_of_match[] __maybe_unused = {
 387         { .compatible = "ti,da850-dsp", },
 388         { /* sentinel */ },
 389 };
 390 MODULE_DEVICE_TABLE(of, davinci_rproc_of_match);
 391
 392 static struct platform_driver da8xx_rproc_driver = {
 393         .probe = da8xx_rproc_probe,
 394         .remove = da8xx_rproc_remove,
 395         .driver = {
 396                 .name = "davinci-rproc",
 397                 .of_match_table = of_match_ptr(davinci_rproc_of_match),
 398         },
 399 };
 400
 401 module_platform_driver(da8xx_rproc_driver);
 402
 403 MODULE_LICENSE("GPL v2");
 404 MODULE_DESCRIPTION("DA8XX Remote Processor control driver");