drivers/remoteproc/da8xx_remoteproc.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Remote processor machine-specific module for DA8XX
   4  *
   5  * Copyright (C) 2013 Texas Instruments, Inc.
   6  */
   7
   8 #include <linux/bitops.h>
   9 #include <linux/clk.h>
  10 #include <linux/reset.h>
  11 #include <linux/err.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/io.h>
  14 #include <linux/irq.h>
  15 #include <linux/kernel.h>
  16 #include <linux/module.h>
  17 #include <linux/of_reserved_mem.h>
  18 #include <linux/platform_device.h>
  19 #include <linux/remoteproc.h>
  20
  21 #include "remoteproc_internal.h"
  22
  23 static char *da8xx_fw_name;
  24 module_param(da8xx_fw_name, charp, 0444);
  25 MODULE_PARM_DESC(da8xx_fw_name,
  26                  "Name of DSP firmware file in /lib/firmware (if not specified defaults to 'rproc-dsp-fw')");
  27
  28 /*
  29  * OMAP-L138 Technical References:
  30  * http://www.ti.com/product/omap-l138
  31  */
  32 #define SYSCFG_CHIPSIG0 BIT(0)
  33 #define SYSCFG_CHIPSIG1 BIT(1)
  34 #define SYSCFG_CHIPSIG2 BIT(2)
  35 #define SYSCFG_CHIPSIG3 BIT(3)
  36 #define SYSCFG_CHIPSIG4 BIT(4)
  37
  38 #define DA8XX_RPROC_LOCAL_ADDRESS_MASK  (SZ_16M - 1)
  39
  40 /**
  41  * struct da8xx_rproc_mem - internal memory structure
  42  * @cpu_addr: MPU virtual address of the memory region
  43  * @bus_addr: Bus address used to access the memory region
  44  * @dev_addr: Device address of the memory region from DSP view
  45  * @size: Size of the memory region
  46  */
  47 struct da8xx_rproc_mem {
  48         void __iomem *cpu_addr;
  49         phys_addr_t bus_addr;
  50         u32 dev_addr;
  51         size_t size;
  52 };
  53
  54 /**
  55  * struct da8xx_rproc - da8xx remote processor instance state
  56  * @rproc: rproc handle
  57  * @mem: internal memory regions data
  58  * @num_mems: number of internal memory regions
  59  * @dsp_clk: placeholder for platform's DSP clk
  60  * @ack_fxn: chip-specific ack function for ack'ing irq
  61  * @irq_data: ack_fxn function parameter
  62  * @chipsig: virt ptr to DSP interrupt registers (CHIPSIG & CHIPSIG_CLR)
  63  * @bootreg: virt ptr to DSP boot address register (HOST1CFG)
  64  * @irq: irq # used by this instance
  65  */
  66 struct da8xx_rproc {
  67         struct rproc *rproc;
  68         struct da8xx_rproc_mem *mem;
  69         int num_mems;
  70         struct clk *dsp_clk;
  71         struct reset_control *dsp_reset;
  72         void (*ack_fxn)(struct irq_data *data);
  73         struct irq_data *irq_data;
  74         void __iomem *chipsig;
  75         void __iomem *bootreg;
  76         int irq;
  77 };
  78
  79 /**
  80  * handle_event() - inbound virtqueue message workqueue function
  81  *
  82  * This function is registered as a kernel thread and is scheduled by the
  83  * kernel handler.
  84  */
  85 static irqreturn_t handle_event(int irq, void *p)
  86 {
  87         struct rproc *rproc = p;
  88
  89         /* Process incoming buffers on all our vrings */
  90         rproc_vq_interrupt(rproc, 0);
  91         rproc_vq_interrupt(rproc, 1);
  92
  93         return IRQ_HANDLED;
  94 }
  95
  96 /**
  97  * da8xx_rproc_callback() - inbound virtqueue message handler
  98  *
  99  * This handler is invoked directly by the kernel whenever the remote
 100  * core (DSP) has modified the state of a virtqueue.  There is no
 101  * "payload" message indicating the virtqueue index as is the case with
 102  * mailbox-based implementations on OMAP4.  As such, this handler "polls"
 103  * each known virtqueue index for every invocation.
 104  */
 105 static irqreturn_t da8xx_rproc_callback(int irq, void *p)
 106 {
 107         struct rproc *rproc = p;
 108         struct da8xx_rproc *drproc = rproc->priv;
 109         u32 chipsig;
 110
 111         chipsig = readl(drproc->chipsig);
 112         if (chipsig & SYSCFG_CHIPSIG0) {
 113                 /* Clear interrupt level source */
 114                 writel(SYSCFG_CHIPSIG0, drproc->chipsig + 4);
 115
 116                 /*
 117                  * ACK intr to AINTC.
 118                  *
 119                  * It has already been ack'ed by the kernel before calling
 120                  * this function, but since the ARM<->DSP interrupts in the
 121                  * CHIPSIG register are "level" instead of "pulse" variety,
 122                  * we need to ack it after taking down the level else we'll
 123                  * be called again immediately after returning.
 124                  */
 125                 drproc->ack_fxn(drproc->irq_data);
 126
 127                 return IRQ_WAKE_THREAD;
 128         }
 129
 130         return IRQ_HANDLED;
 131 }
 132
 133 static int da8xx_rproc_start(struct rproc *rproc)
 134 {
 135         struct device *dev = rproc->dev.parent;
 136         struct da8xx_rproc *drproc = rproc->priv;
 137         struct clk *dsp_clk = drproc->dsp_clk;
 138         struct reset_control *dsp_reset = drproc->dsp_reset;
 139         int ret;
 140
 141         /* hw requires the start (boot) address be on 1KB boundary */
 142         if (rproc->bootaddr & 0x3ff) {
 143                 dev_err(dev, "invalid boot address: must be aligned to 1KB\n");
 144
 145                 return -EINVAL;
 146         }
 147
 148         writel(rproc->bootaddr, drproc->bootreg);
 149
 150         ret = clk_prepare_enable(dsp_clk);
 151         if (ret) {
 152                 dev_err(dev, "clk_prepare_enable() failed: %d\n", ret);
 153                 return ret;
 154         }
 155
 156         ret = reset_control_deassert(dsp_reset);
 157         if (ret) {
 158                 dev_err(dev, "reset_control_deassert() failed: %d\n", ret);
 159                 clk_disable_unprepare(dsp_clk);
 160                 return ret;
 161         }
 162
 163         return 0;
 164 }
 165
 166 static int da8xx_rproc_stop(struct rproc *rproc)
 167 {
 168         struct da8xx_rproc *drproc = rproc->priv;
 169         struct device *dev = rproc->dev.parent;
 170         int ret;
 171
 172         ret = reset_control_assert(drproc->dsp_reset);
 173         if (ret) {
 174                 dev_err(dev, "reset_control_assert() failed: %d\n", ret);
 175                 return ret;
 176         }
 177
 178         clk_disable_unprepare(drproc->dsp_clk);
 179
 180         return 0;
 181 }
 182
 183 /* kick a virtqueue */
 184 static void da8xx_rproc_kick(struct rproc *rproc, int vqid)
 185 {
 186         struct da8xx_rproc *drproc = rproc->priv;
 187
 188         /* Interrupt remote proc */
 189         writel(SYSCFG_CHIPSIG2, drproc->chipsig);
 190 }
 191
 192 static const struct rproc_ops da8xx_rproc_ops = {
 193         .start = da8xx_rproc_start,
 194         .stop = da8xx_rproc_stop,
 195         .kick = da8xx_rproc_kick,
 196 };
 197
 198 static int da8xx_rproc_get_internal_memories(struct platform_device *pdev,
 199                                              struct da8xx_rproc *drproc)
 200 {
 201         static const char * const mem_names[] = {"l2sram", "l1pram", "l1dram"};
 202         int num_mems = ARRAY_SIZE(mem_names);
 203         struct device *dev = &pdev->dev;
 204         struct resource *res;
 205         int i;
 206
 207         drproc->mem = devm_kcalloc(dev, num_mems, sizeof(*drproc->mem),
 208                                    GFP_KERNEL);
 209         if (!drproc->mem)
 210                 return -ENOMEM;
 211
 212         for (i = 0; i < num_mems; i++) {
 213                 res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
 214                                                    mem_names[i]);
 215                 drproc->mem[i].cpu_addr = devm_ioremap_resource(dev, res);
 216                 if (IS_ERR(drproc->mem[i].cpu_addr)) {
 217                         dev_err(dev, "failed to parse and map %s memory\n",
 218                                 mem_names[i]);
 219                         return PTR_ERR(drproc->mem[i].cpu_addr);
 220                 }
 221                 drproc->mem[i].bus_addr = res->start;
 222                 drproc->mem[i].dev_addr =
 223                                 res->start & DA8XX_RPROC_LOCAL_ADDRESS_MASK;
 224                 drproc->mem[i].size = resource_size(res);
 225
 226                 dev_dbg(dev, "memory %8s: bus addr %pa size 0x%zx va %p da 0x%x\n",
 227                         mem_names[i], &drproc->mem[i].bus_addr,
 228                         drproc->mem[i].size, drproc->mem[i].cpu_addr,
 229                         drproc->mem[i].dev_addr);
 230         }
 231         drproc->num_mems = num_mems;
 232
 233         return 0;
 234 }
 235
 236 static int da8xx_rproc_probe(struct platform_device *pdev)
 237 {
 238         struct device *dev = &pdev->dev;
 239         struct da8xx_rproc *drproc;
 240         struct rproc *rproc;
 241         struct irq_data *irq_data;
 242         struct clk *dsp_clk;
 243         struct reset_control *dsp_reset;
 244         void __iomem *chipsig;
 245         void __iomem *bootreg;
 246         int irq;
 247         int ret;
 248
 249         irq = platform_get_irq(pdev, 0);
 250         if (irq < 0)
 251                 return irq;
 252
 253         irq_data = irq_get_irq_data(irq);
 254         if (!irq_data)
 255                 return dev_err_probe(dev, -EINVAL, "irq_get_irq_data(%d): NULL\n", irq);
 256
 257         bootreg = devm_platform_ioremap_resource_byname(pdev, "host1cfg");
 258         if (IS_ERR(bootreg))
 259                 return PTR_ERR(bootreg);
 260
 261         chipsig = devm_platform_ioremap_resource_byname(pdev, "chipsig");
 262         if (IS_ERR(chipsig))
 263                 return PTR_ERR(chipsig);
 264
 265         dsp_clk = devm_clk_get(dev, NULL);
 266         if (IS_ERR(dsp_clk))
 267                 return dev_err_probe(dev, PTR_ERR(dsp_clk), "clk_get error\n");
 268
 269         dsp_reset = devm_reset_control_get_exclusive(dev, NULL);
 270         if (IS_ERR(dsp_reset))
 271                 return dev_err_probe(dev, PTR_ERR(dsp_reset), "unable to get reset control\n");
 272
 273         if (dev->of_node) {
 274                 ret = of_reserved_mem_device_init(dev);
 275                 if (ret)
 276                         return dev_err_probe(dev, ret, "device does not have specific CMA pool\n");
 277         }
 278
 279         rproc = rproc_alloc(dev, "dsp", &da8xx_rproc_ops, da8xx_fw_name,
 280                 sizeof(*drproc));
 281         if (!rproc) {
 282                 ret = -ENOMEM;
 283                 goto free_mem;
 284         }
 285
 286         /* error recovery is not supported at present */
 287         rproc->recovery_disabled = true;
 288
 289         drproc = rproc->priv;
 290         drproc->rproc = rproc;
 291         drproc->dsp_clk = dsp_clk;
 292         drproc->dsp_reset = dsp_reset;
 293         rproc->has_iommu = false;
 294
 295         ret = da8xx_rproc_get_internal_memories(pdev, drproc);
 296         if (ret)
 297                 goto free_rproc;
 298
 299         platform_set_drvdata(pdev, rproc);
 300
 301         /* everything the ISR needs is now setup, so hook it up */
 302         ret = devm_request_threaded_irq(dev, irq, da8xx_rproc_callback,
 303                                         handle_event, 0, "da8xx-remoteproc",
 304                                         rproc);
 305         if (ret) {
 306                 dev_err(dev, "devm_request_threaded_irq error: %d\n", ret);
 307                 goto free_rproc;
 308         }
 309
 310         /*
 311          * rproc_add() can end up enabling the DSP's clk with the DSP
 312          * *not* in reset, but da8xx_rproc_start() needs the DSP to be
 313          * held in reset at the time it is called.
 314          */
 315         ret = reset_control_assert(dsp_reset);
 316         if (ret)
 317                 goto free_rproc;
 318
 319         drproc->chipsig = chipsig;
 320         drproc->bootreg = bootreg;
 321         drproc->ack_fxn = irq_data->chip->irq_ack;
 322         drproc->irq_data = irq_data;
 323         drproc->irq = irq;
 324
 325         ret = rproc_add(rproc);
 326         if (ret) {
 327                 dev_err(dev, "rproc_add failed: %d\n", ret);
 328                 goto free_rproc;
 329         }
 330
 331         return 0;
 332
 333 free_rproc:
 334         rproc_free(rproc);
 335 free_mem:
 336         if (dev->of_node)
 337                 of_reserved_mem_device_release(dev);
 338         return ret;
 339 }
 340
 341 static void da8xx_rproc_remove(struct platform_device *pdev)
 342 {
 343         struct rproc *rproc = platform_get_drvdata(pdev);
 344         struct da8xx_rproc *drproc = rproc->priv;
 345         struct device *dev = &pdev->dev;
 346
 347         /*
 348          * The devm subsystem might end up releasing things before
 349          * freeing the irq, thus allowing an interrupt to sneak in while
 350          * the device is being removed.  This should prevent that.
 351          */
 352         disable_irq(drproc->irq);
 353
 354         rproc_del(rproc);
 355         rproc_free(rproc);
 356         if (dev->of_node)
 357                 of_reserved_mem_device_release(dev);
 358 }
 359
 360 static const struct of_device_id davinci_rproc_of_match[] __maybe_unused = {
 361         { .compatible = "ti,da850-dsp", },
 362         { /* sentinel */ },
 363 };
 364 MODULE_DEVICE_TABLE(of, davinci_rproc_of_match);
 365
 366 static struct platform_driver da8xx_rproc_driver = {
 367         .probe = da8xx_rproc_probe,
 368         .remove = da8xx_rproc_remove,
 369         .driver = {
 370                 .name = "davinci-rproc",
 371                 .of_match_table = of_match_ptr(davinci_rproc_of_match),
 372         },
 373 };
 374
 375 module_platform_driver(da8xx_rproc_driver);
 376
 377 MODULE_LICENSE("GPL v2");
 378 MODULE_DESCRIPTION("DA8XX Remote Processor control driver");