// SPDX-License-Identifier: GPL-2.0-or-later /* * pxa3xx-gcu.c - Linux kernel module for PXA3xx graphics controllers * * This driver needs a DirectFB counterpart in user space, communication * is handled via mmap()ed memory areas and an ioctl. * * Copyright (c) 2009 Daniel Mack * Copyright (c) 2009 Janine Kropp * Copyright (c) 2009 Denis Oliver Kropp */ /* * WARNING: This controller is attached to System Bus 2 of the PXA which * needs its arbiter to be enabled explicitly (CKENB & 1<<9). * There is currently no way to do this from Linux, so you need to teach * your bootloader for now. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "pxa3xx-gcu.h" #define DRV_NAME "pxa3xx-gcu" #define REG_GCCR 0x00 #define GCCR_SYNC_CLR (1 << 9) #define GCCR_BP_RST (1 << 8) #define GCCR_ABORT (1 << 6) #define GCCR_STOP (1 << 4) #define REG_GCISCR 0x04 #define REG_GCIECR 0x08 #define REG_GCRBBR 0x20 #define REG_GCRBLR 0x24 #define REG_GCRBHR 0x28 #define REG_GCRBTR 0x2C #define REG_GCRBEXHR 0x30 #define IE_EOB (1 << 0) #define IE_EEOB (1 << 5) #define IE_ALL 0xff #define SHARED_SIZE PAGE_ALIGN(sizeof(struct pxa3xx_gcu_shared)) /* #define PXA3XX_GCU_DEBUG */ /* #define PXA3XX_GCU_DEBUG_TIMER */ #ifdef PXA3XX_GCU_DEBUG #define QDUMP(msg) \ do { \ QPRINT(priv, KERN_DEBUG, msg); \ } while (0) #else #define QDUMP(msg) do {} while (0) #endif #define QERROR(msg) \ do { \ QPRINT(priv, KERN_ERR, msg); \ } while (0) struct pxa3xx_gcu_batch { struct pxa3xx_gcu_batch *next; u32 *ptr; dma_addr_t phys; unsigned long length; }; struct pxa3xx_gcu_priv { struct device *dev; void __iomem *mmio_base; struct clk *clk; struct pxa3xx_gcu_shared *shared; dma_addr_t shared_phys; struct resource *resource_mem; struct miscdevice misc_dev; wait_queue_head_t wait_idle; wait_queue_head_t wait_free; spinlock_t spinlock; struct timespec64 base_time; struct pxa3xx_gcu_batch *free; struct pxa3xx_gcu_batch *ready; struct pxa3xx_gcu_batch *ready_last; struct pxa3xx_gcu_batch *running; }; static inline unsigned long gc_readl(struct pxa3xx_gcu_priv *priv, unsigned int off) { return __raw_readl(priv->mmio_base + off); } static inline void gc_writel(struct pxa3xx_gcu_priv *priv, unsigned int off, unsigned long val) { __raw_writel(val, priv->mmio_base + off); } #define QPRINT(priv, level, msg) \ do { \ struct timespec64 ts; \ struct pxa3xx_gcu_shared *shared = priv->shared; \ u32 base = gc_readl(priv, REG_GCRBBR); \ \ ktime_get_ts64(&ts); \ ts = timespec64_sub(ts, priv->base_time); \ \ printk(level "%lld.%03ld.%03ld - %-17s: %-21s (%s, " \ "STATUS " \ "0x%02lx, B 0x%08lx [%ld], E %5ld, H %5ld, " \ "T %5ld)\n", \ (s64)(ts.tv_sec), \ ts.tv_nsec / NSEC_PER_MSEC, \ (ts.tv_nsec % NSEC_PER_MSEC) / USEC_PER_MSEC, \ __func__, msg, \ shared->hw_running ? "running" : " idle", \ gc_readl(priv, REG_GCISCR), \ gc_readl(priv, REG_GCRBBR), \ gc_readl(priv, REG_GCRBLR), \ (gc_readl(priv, REG_GCRBEXHR) - base) / 4, \ (gc_readl(priv, REG_GCRBHR) - base) / 4, \ (gc_readl(priv, REG_GCRBTR) - base) / 4); \ } while (0) static void pxa3xx_gcu_reset(struct pxa3xx_gcu_priv *priv) { QDUMP("RESET"); /* disable interrupts */ gc_writel(priv, REG_GCIECR, 0); /* reset hardware */ gc_writel(priv, REG_GCCR, GCCR_ABORT); gc_writel(priv, REG_GCCR, 0); memset(priv->shared, 0, SHARED_SIZE); priv->shared->buffer_phys = priv->shared_phys; priv->shared->magic = PXA3XX_GCU_SHARED_MAGIC; ktime_get_ts64(&priv->base_time); /* set up the ring buffer pointers */ gc_writel(priv, REG_GCRBLR, 0); gc_writel(priv, REG_GCRBBR, priv->shared_phys); gc_writel(priv, REG_GCRBTR, priv->shared_phys); /* enable all IRQs except EOB */ gc_writel(priv, REG_GCIECR, IE_ALL & ~IE_EOB); } static void dump_whole_state(struct pxa3xx_gcu_priv *priv) { struct pxa3xx_gcu_shared *sh = priv->shared; u32 base = gc_readl(priv, REG_GCRBBR); QDUMP("DUMP"); printk(KERN_DEBUG "== PXA3XX-GCU DUMP ==\n" "%s, STATUS 0x%02lx, B 0x%08lx [%ld], E %5ld, H %5ld, T %5ld\n", sh->hw_running ? "running" : "idle ", gc_readl(priv, REG_GCISCR), gc_readl(priv, REG_GCRBBR), gc_readl(priv, REG_GCRBLR), (gc_readl(priv, REG_GCRBEXHR) - base) / 4, (gc_readl(priv, REG_GCRBHR) - base) / 4, (gc_readl(priv, REG_GCRBTR) - base) / 4); } static void flush_running(struct pxa3xx_gcu_priv *priv) { struct pxa3xx_gcu_batch *running = priv->running; struct pxa3xx_gcu_batch *next; while (running) { next = running->next; running->next = priv->free; priv->free = running; running = next; } priv->running = NULL; } static void run_ready(struct pxa3xx_gcu_priv *priv) { unsigned int num = 0; struct pxa3xx_gcu_shared *shared = priv->shared; struct pxa3xx_gcu_batch *ready = priv->ready; QDUMP("Start"); BUG_ON(!ready); shared->buffer[num++] = 0x05000000; while (ready) { shared->buffer[num++] = 0x00000001; shared->buffer[num++] = ready->phys; ready = ready->next; } shared->buffer[num++] = 0x05000000; priv->running = priv->ready; priv->ready = priv->ready_last = NULL; gc_writel(priv, REG_GCRBLR, 0); shared->hw_running = 1; /* ring base address */ gc_writel(priv, REG_GCRBBR, shared->buffer_phys); /* ring tail address */ gc_writel(priv, REG_GCRBTR, shared->buffer_phys + num * 4); /* ring length */ gc_writel(priv, REG_GCRBLR, ((num + 63) & ~63) * 4); } static irqreturn_t pxa3xx_gcu_handle_irq(int irq, void *ctx) { struct pxa3xx_gcu_priv *priv = ctx; struct pxa3xx_gcu_shared *shared = priv->shared; u32 status = gc_readl(priv, REG_GCISCR) & IE_ALL; QDUMP("-Interrupt"); if (!status) return IRQ_NONE; spin_lock(&priv->spinlock); shared->num_interrupts++; if (status & IE_EEOB) { QDUMP(" [EEOB]"); flush_running(priv); wake_up_all(&priv->wait_free); if (priv->ready) { run_ready(priv); } else { /* There is no more data prepared by the userspace. * Set hw_running = 0 and wait for the next userspace * kick-off */ shared->num_idle++; shared->hw_running = 0; QDUMP(" '-> Idle."); /* set ring buffer length to zero */ gc_writel(priv, REG_GCRBLR, 0); wake_up_all(&priv->wait_idle); } shared->num_done++; } else { QERROR(" [???]"); dump_whole_state(priv); } /* Clear the interrupt */ gc_writel(priv, REG_GCISCR, status); spin_unlock(&priv->spinlock); return IRQ_HANDLED; } static int pxa3xx_gcu_wait_idle(struct pxa3xx_gcu_priv *priv) { int ret = 0; QDUMP("Waiting for idle..."); /* Does not need to be atomic. There's a lock in user space, * but anyhow, this is just for statistics. */ priv->shared->num_wait_idle++; while (priv->shared->hw_running) { int num = priv->shared->num_interrupts; u32 rbexhr = gc_readl(priv, REG_GCRBEXHR); ret = wait_event_interruptible_timeout(priv->wait_idle, !priv->shared->hw_running, HZ*4); if (ret != 0) break; if (gc_readl(priv, REG_GCRBEXHR) == rbexhr && priv->shared->num_interrupts == num) { QERROR("TIMEOUT"); ret = -ETIMEDOUT; break; } } QDUMP("done"); return ret; } static int pxa3xx_gcu_wait_free(struct pxa3xx_gcu_priv *priv) { int ret = 0; QDUMP("Waiting for free..."); /* Does not need to be atomic. There's a lock in user space, * but anyhow, this is just for statistics. */ priv->shared->num_wait_free++; while (!priv->free) { u32 rbexhr = gc_readl(priv, REG_GCRBEXHR); ret = wait_event_interruptible_timeout(priv->wait_free, priv->free, HZ*4); if (ret < 0) break; if (ret > 0) continue; if (gc_readl(priv, REG_GCRBEXHR) == rbexhr) { QERROR("TIMEOUT"); ret = -ETIMEDOUT; break; } } QDUMP("done"); return ret; } /* Misc device layer */ static inline struct pxa3xx_gcu_priv *to_pxa3xx_gcu_priv(struct file *file) { struct miscdevice *dev = file->private_data; return container_of(dev, struct pxa3xx_gcu_priv, misc_dev); } /* * provide an empty .open callback, so the core sets file->private_data * for us. */ static int pxa3xx_gcu_open(struct inode *inode, struct file *file) { return 0; } static ssize_t pxa3xx_gcu_write(struct file *file, const char *buff, size_t count, loff_t *offp) { int ret; unsigned long flags; struct pxa3xx_gcu_batch *buffer; struct pxa3xx_gcu_priv *priv = to_pxa3xx_gcu_priv(file); size_t words = count / 4; /* Does not need to be atomic. There's a lock in user space, * but anyhow, this is just for statistics. */ priv->shared->num_writes++; priv->shared->num_words += words; /* Last word reserved for batch buffer end command */ if (words >= PXA3XX_GCU_BATCH_WORDS) return -E2BIG; /* Wait for a free buffer */ if (!priv->free) { ret = pxa3xx_gcu_wait_free(priv); if (ret < 0) return ret; } /* * Get buffer from free list */ spin_lock_irqsave(&priv->spinlock, flags); buffer = priv->free; priv->free = buffer->next; spin_unlock_irqrestore(&priv->spinlock, flags); /* Copy data from user into buffer */ ret = copy_from_user(buffer->ptr, buff, words * 4); if (ret) { spin_lock_irqsave(&priv->spinlock, flags); buffer->next = priv->free; priv->free = buffer; spin_unlock_irqrestore(&priv->spinlock, flags); return -EFAULT; } buffer->length = words; /* Append batch buffer end command */ buffer->ptr[words] = 0x01000000; /* * Add buffer to ready list */ spin_lock_irqsave(&priv->spinlock, flags); buffer->next = NULL; if (priv->ready) { BUG_ON(priv->ready_last == NULL); priv->ready_last->next = buffer; } else priv->ready = buffer; priv->ready_last = buffer; if (!priv->shared->hw_running) run_ready(priv); spin_unlock_irqrestore(&priv->spinlock, flags); return words * 4; } static long pxa3xx_gcu_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { unsigned long flags; struct pxa3xx_gcu_priv *priv = to_pxa3xx_gcu_priv(file); switch (cmd) { case PXA3XX_GCU_IOCTL_RESET: spin_lock_irqsave(&priv->spinlock, flags); pxa3xx_gcu_reset(priv); spin_unlock_irqrestore(&priv->spinlock, flags); return 0; case PXA3XX_GCU_IOCTL_WAIT_IDLE: return pxa3xx_gcu_wait_idle(priv); } return -ENOSYS; } static int pxa3xx_gcu_mmap(struct file *file, struct vm_area_struct *vma) { unsigned int size = vma->vm_end - vma->vm_start; struct pxa3xx_gcu_priv *priv = to_pxa3xx_gcu_priv(file); switch (vma->vm_pgoff) { case 0: /* hand out the shared data area */ if (size != SHARED_SIZE) return -EINVAL; return dma_mmap_coherent(priv->dev, vma, priv->shared, priv->shared_phys, size); case SHARED_SIZE >> PAGE_SHIFT: /* hand out the MMIO base for direct register access * from userspace */ if (size != resource_size(priv->resource_mem)) return -EINVAL; vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); return io_remap_pfn_range(vma, vma->vm_start, priv->resource_mem->start >> PAGE_SHIFT, size, vma->vm_page_prot); } return -EINVAL; } #ifdef PXA3XX_GCU_DEBUG_TIMER static struct timer_list pxa3xx_gcu_debug_timer; static struct pxa3xx_gcu_priv *debug_timer_priv; static void pxa3xx_gcu_debug_timedout(struct timer_list *unused) { struct pxa3xx_gcu_priv *priv = debug_timer_priv; QERROR("Timer DUMP"); mod_timer(&pxa3xx_gcu_debug_timer, jiffies + 5 * HZ); } static void pxa3xx_gcu_init_debug_timer(struct pxa3xx_gcu_priv *priv) { /* init the timer structure */ debug_timer_priv = priv; timer_setup(&pxa3xx_gcu_debug_timer, pxa3xx_gcu_debug_timedout, 0); pxa3xx_gcu_debug_timedout(NULL); } #else static inline void pxa3xx_gcu_init_debug_timer(struct pxa3xx_gcu_priv *priv) {} #endif static int pxa3xx_gcu_add_buffer(struct device *dev, struct pxa3xx_gcu_priv *priv) { struct pxa3xx_gcu_batch *buffer; buffer = kzalloc(sizeof(struct pxa3xx_gcu_batch), GFP_KERNEL); if (!buffer) return -ENOMEM; buffer->ptr = dma_alloc_coherent(dev, PXA3XX_GCU_BATCH_WORDS * 4, &buffer->phys, GFP_KERNEL); if (!buffer->ptr) { kfree(buffer); return -ENOMEM; } buffer->next = priv->free; priv->free = buffer; return 0; } static void pxa3xx_gcu_free_buffers(struct device *dev, struct pxa3xx_gcu_priv *priv) { struct pxa3xx_gcu_batch *next, *buffer = priv->free; while (buffer) { next = buffer->next; dma_free_coherent(dev, PXA3XX_GCU_BATCH_WORDS * 4, buffer->ptr, buffer->phys); kfree(buffer); buffer = next; } priv->free = NULL; } static const struct file_operations pxa3xx_gcu_miscdev_fops = { .owner = THIS_MODULE, .open = pxa3xx_gcu_open, .write = pxa3xx_gcu_write, .unlocked_ioctl = pxa3xx_gcu_ioctl, .mmap = pxa3xx_gcu_mmap, }; static int pxa3xx_gcu_probe(struct platform_device *pdev) { int i, ret, irq; struct resource *r; struct pxa3xx_gcu_priv *priv; struct device *dev = &pdev->dev; priv = devm_kzalloc(dev, sizeof(struct pxa3xx_gcu_priv), GFP_KERNEL); if (!priv) return -ENOMEM; init_waitqueue_head(&priv->wait_idle); init_waitqueue_head(&priv->wait_free); spin_lock_init(&priv->spinlock); /* we allocate the misc device structure as part of our own allocation, * so we can get a pointer to our priv structure later on with * container_of(). This isn't really necessary as we have a fixed minor * number anyway, but this is to avoid statics. */ priv->misc_dev.minor = PXA3XX_GCU_MINOR; priv->misc_dev.name = DRV_NAME; priv->misc_dev.fops = &pxa3xx_gcu_miscdev_fops; /* handle IO resources */ priv->mmio_base = devm_platform_get_and_ioremap_resource(pdev, 0, &r); if (IS_ERR(priv->mmio_base)) return PTR_ERR(priv->mmio_base); /* enable the clock */ priv->clk = devm_clk_get(dev, NULL); if (IS_ERR(priv->clk)) return dev_err_probe(dev, PTR_ERR(priv->clk), "failed to get clock\n"); /* request the IRQ */ irq = platform_get_irq(pdev, 0); if (irq < 0) return irq; ret = devm_request_irq(dev, irq, pxa3xx_gcu_handle_irq, 0, DRV_NAME, priv); if (ret < 0) { dev_err(dev, "request_irq failed\n"); return ret; } /* allocate dma memory */ priv->shared = dma_alloc_coherent(dev, SHARED_SIZE, &priv->shared_phys, GFP_KERNEL); if (!priv->shared) { dev_err(dev, "failed to allocate DMA memory\n"); return -ENOMEM; } /* register misc device */ ret = misc_register(&priv->misc_dev); if (ret < 0) { dev_err(dev, "misc_register() for minor %d failed\n", PXA3XX_GCU_MINOR); goto err_free_dma; } ret = clk_prepare_enable(priv->clk); if (ret < 0) { dev_err(dev, "failed to enable clock\n"); goto err_misc_deregister; } for (i = 0; i < 8; i++) { ret = pxa3xx_gcu_add_buffer(dev, priv); if (ret) { pxa3xx_gcu_free_buffers(dev, priv); dev_err(dev, "failed to allocate DMA memory\n"); goto err_disable_clk; } } platform_set_drvdata(pdev, priv); priv->resource_mem = r; priv->dev = dev; pxa3xx_gcu_reset(priv); pxa3xx_gcu_init_debug_timer(priv); dev_info(dev, "registered @0x%p, DMA 0x%p (%d bytes), IRQ %d\n", (void *) r->start, (void *) priv->shared_phys, SHARED_SIZE, irq); return 0; err_disable_clk: clk_disable_unprepare(priv->clk); err_misc_deregister: misc_deregister(&priv->misc_dev); err_free_dma: dma_free_coherent(dev, SHARED_SIZE, priv->shared, priv->shared_phys); return ret; } static void pxa3xx_gcu_remove(struct platform_device *pdev) { struct pxa3xx_gcu_priv *priv = platform_get_drvdata(pdev); struct device *dev = &pdev->dev; pxa3xx_gcu_wait_idle(priv); misc_deregister(&priv->misc_dev); dma_free_coherent(dev, SHARED_SIZE, priv->shared, priv->shared_phys); clk_disable_unprepare(priv->clk); pxa3xx_gcu_free_buffers(dev, priv); } #ifdef CONFIG_OF static const struct of_device_id pxa3xx_gcu_of_match[] = { { .compatible = "marvell,pxa300-gcu", }, { } }; MODULE_DEVICE_TABLE(of, pxa3xx_gcu_of_match); #endif static struct platform_driver pxa3xx_gcu_driver = { .probe = pxa3xx_gcu_probe, .remove = pxa3xx_gcu_remove, .driver = { .name = DRV_NAME, .of_match_table = of_match_ptr(pxa3xx_gcu_of_match), }, }; module_platform_driver(pxa3xx_gcu_driver); MODULE_DESCRIPTION("PXA3xx graphics controller unit driver"); MODULE_LICENSE("GPL"); MODULE_ALIAS_MISCDEV(PXA3XX_GCU_MINOR); MODULE_AUTHOR("Janine Kropp , " "Denis Oliver Kropp , " "Daniel Mack ");