diff options
Diffstat (limited to 'drivers/video/fbdev/pxa3xx-gcu.c')
| -rw-r--r-- | drivers/video/fbdev/pxa3xx-gcu.c | 717 |
1 files changed, 717 insertions, 0 deletions
diff --git a/drivers/video/fbdev/pxa3xx-gcu.c b/drivers/video/fbdev/pxa3xx-gcu.c new file mode 100644 index 000000000..c3cd1e1cc --- /dev/null +++ b/drivers/video/fbdev/pxa3xx-gcu.c @@ -0,0 +1,717 @@ +// 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 <daniel@caiaq.de> + * Copyright (c) 2009 Janine Kropp <nin@directfb.org> + * Copyright (c) 2009 Denis Oliver Kropp <dok@directfb.org> + */ + +/* + * 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 <linux/module.h> +#include <linux/platform_device.h> +#include <linux/dma-mapping.h> +#include <linux/miscdevice.h> +#include <linux/interrupt.h> +#include <linux/spinlock.h> +#include <linux/uaccess.h> +#include <linux/ioctl.h> +#include <linux/delay.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/clk.h> +#include <linux/fs.h> +#include <linux/io.h> +#include <linux/of.h> + +#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 */ + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + priv->mmio_base = devm_ioremap_resource(dev, 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 int 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); + + return 0; +} + +#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 <nin@directfb.org>, " + "Denis Oliver Kropp <dok@directfb.org>, " + "Daniel Mack <daniel@caiaq.de>"); |