[deliverable/linux.git] / drivers / video / via / via-core.c

/*
 * Copyright 1998-2009 VIA Technologies, Inc. All Rights Reserved.
 * Copyright 2001-2008 S3 Graphics, Inc. All Rights Reserved.
 * Copyright 2009 Jonathan Corbet <corbet@lwn.net>
 */

/*
 * Core code for the Via multifunction framebuffer device.
 */
#include <linux/via-core.h>
#include <linux/via_i2c.h>
#include <linux/via-gpio.h>
#include "global.h"

#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>

/*
 * The default port config.
 */
static struct via_port_cfg adap_configs[] = {
        [VIA_PORT_26]   = { VIA_PORT_I2C,  VIA_MODE_OFF, VIASR, 0x26 },
        [VIA_PORT_31]   = { VIA_PORT_I2C,  VIA_MODE_I2C, VIASR, 0x31 },
        [VIA_PORT_25]   = { VIA_PORT_GPIO, VIA_MODE_GPIO, VIASR, 0x25 },
        [VIA_PORT_2C]   = { VIA_PORT_GPIO, VIA_MODE_I2C, VIASR, 0x2c },
        [VIA_PORT_3D]   = { VIA_PORT_GPIO, VIA_MODE_GPIO, VIASR, 0x3d },
        { 0, 0, 0, 0 }
};

/*
 * We currently only support one viafb device (will there ever be
 * more than one?), so just declare it globally here.
 */
static struct viafb_dev global_dev;


/*
 * Basic register access; spinlock required.
 */
static inline void viafb_mmio_write(int reg, u32 v)
{
        iowrite32(v, global_dev.engine_mmio + reg);
}

static inline int viafb_mmio_read(int reg)
{
        return ioread32(global_dev.engine_mmio + reg);
}

/* ---------------------------------------------------------------------- */
/*
 * Interrupt management.  We have a single IRQ line for a lot of
 * different functions, so we need to share it.  The design here
 * is that we don't want to reimplement the shared IRQ code here;
 * we also want to avoid having contention for a single handler thread.
 * So each subdev driver which needs interrupts just requests
 * them directly from the kernel.  We just have what's needed for
 * overall access to the interrupt control register.
 */

/*
 * Which interrupts are enabled now?
 */
static u32 viafb_enabled_ints;

static void __devinit viafb_int_init(void)
{
        viafb_enabled_ints = 0;

        viafb_mmio_write(VDE_INTERRUPT, 0);
}

/*
 * Allow subdevs to ask for specific interrupts to be enabled.  These
 * functions must be called with reg_lock held
 */
void viafb_irq_enable(u32 mask)
{
        viafb_enabled_ints |= mask;
        viafb_mmio_write(VDE_INTERRUPT, viafb_enabled_ints | VDE_I_ENABLE);
}
EXPORT_SYMBOL_GPL(viafb_irq_enable);

void viafb_irq_disable(u32 mask)
{
        viafb_enabled_ints &= ~mask;
        if (viafb_enabled_ints == 0)
                viafb_mmio_write(VDE_INTERRUPT, 0);  /* Disable entirely */
        else
                viafb_mmio_write(VDE_INTERRUPT,
                                viafb_enabled_ints | VDE_I_ENABLE);
}
EXPORT_SYMBOL_GPL(viafb_irq_disable);

/* ---------------------------------------------------------------------- */
/*
 * Currently, the camera driver is the only user of the DMA code, so we
 * only compile it in if the camera driver is being built.  Chances are,
 * most viafb systems will not need to have this extra code for a while.
 * As soon as another user comes long, the ifdef can be removed.
 */
#if defined(CONFIG_VIDEO_VIA_CAMERA) || defined(CONFIG_VIDEO_VIA_CAMERA_MODULE)
/*
 * Access to the DMA engine.  This currently provides what the camera
 * driver needs (i.e. outgoing only) but is easily expandable if need
 * be.
 */

/*
 * There are four DMA channels in the vx855.  For now, we only
 * use one of them, though.  Most of the time, the DMA channel
 * will be idle, so we keep the IRQ handler unregistered except
 * when some subsystem has indicated an interest.
 */
static int viafb_dma_users;
static DECLARE_COMPLETION(viafb_dma_completion);
/*
 * This mutex protects viafb_dma_users and our global interrupt
 * registration state; it also serializes access to the DMA
 * engine.
 */
static DEFINE_MUTEX(viafb_dma_lock);

/*
 * The VX855 DMA descriptor (used for s/g transfers) looks
 * like this.
 */
struct viafb_vx855_dma_descr {
        u32     addr_low;       /* Low part of phys addr */
        u32     addr_high;      /* High 12 bits of addr */
        u32     fb_offset;      /* Offset into FB memory */
        u32     seg_size;       /* Size, 16-byte units */
        u32     tile_mode;      /* "tile mode" setting */
        u32     next_desc_low;  /* Next descriptor addr */
        u32     next_desc_high;
        u32     pad;            /* Fill out to 64 bytes */
};

/*
 * Flags added to the "next descriptor low" pointers
 */
#define VIAFB_DMA_MAGIC         0x01  /* ??? Just has to be there */
#define VIAFB_DMA_FINAL_SEGMENT 0x02  /* Final segment */

/*
 * The completion IRQ handler.
 */
static irqreturn_t viafb_dma_irq(int irq, void *data)
{
        int csr;
        irqreturn_t ret = IRQ_NONE;

        spin_lock(&global_dev.reg_lock);
        csr = viafb_mmio_read(VDMA_CSR0);
        if (csr & VDMA_C_DONE) {
                viafb_mmio_write(VDMA_CSR0, VDMA_C_DONE);
                complete(&viafb_dma_completion);
                ret = IRQ_HANDLED;
        }
        spin_unlock(&global_dev.reg_lock);
        return ret;
}

/*
 * Indicate a need for DMA functionality.
 */
int viafb_request_dma(void)
{
        int ret = 0;

        /*
         * Only VX855 is supported currently.
         */
        if (global_dev.chip_type != UNICHROME_VX855)
                return -ENODEV;
        /*
         * Note the new user and set up our interrupt handler
         * if need be.
         */
        mutex_lock(&viafb_dma_lock);
        viafb_dma_users++;
        if (viafb_dma_users == 1) {
                ret = request_irq(global_dev.pdev->irq, viafb_dma_irq,
                                IRQF_SHARED, "via-dma", &viafb_dma_users);
                if (ret)
                        viafb_dma_users--;
                else
                        viafb_irq_enable(VDE_I_DMA0TDEN);
        }
        mutex_unlock(&viafb_dma_lock);
        return ret;
}
EXPORT_SYMBOL_GPL(viafb_request_dma);

void viafb_release_dma(void)
{
        mutex_lock(&viafb_dma_lock);
        viafb_dma_users--;
        if (viafb_dma_users == 0) {
                viafb_irq_disable(VDE_I_DMA0TDEN);
                free_irq(global_dev.pdev->irq, &viafb_dma_users);
        }
        mutex_unlock(&viafb_dma_lock);
}
EXPORT_SYMBOL_GPL(viafb_release_dma);


#if 0
/*
 * Copy a single buffer from FB memory, synchronously.  This code works
 * but is not currently used.
 */
void viafb_dma_copy_out(unsigned int offset, dma_addr_t paddr, int len)
{
        unsigned long flags;
        int csr;

        mutex_lock(&viafb_dma_lock);
        init_completion(&viafb_dma_completion);
        /*
         * Program the controller.
         */
        spin_lock_irqsave(&global_dev.reg_lock, flags);
        viafb_mmio_write(VDMA_CSR0, VDMA_C_ENABLE|VDMA_C_DONE);
        /* Enable ints; must happen after CSR0 write! */
        viafb_mmio_write(VDMA_MR0, VDMA_MR_TDIE);
        viafb_mmio_write(VDMA_MARL0, (int) (paddr & 0xfffffff0));
        viafb_mmio_write(VDMA_MARH0, (int) ((paddr >> 28) & 0xfff));
        /* Data sheet suggests DAR0 should be <<4, but it lies */
        viafb_mmio_write(VDMA_DAR0, offset);
        viafb_mmio_write(VDMA_DQWCR0, len >> 4);
        viafb_mmio_write(VDMA_TMR0, 0);
        viafb_mmio_write(VDMA_DPRL0, 0);
        viafb_mmio_write(VDMA_DPRH0, 0);
        viafb_mmio_write(VDMA_PMR0, 0);
        csr = viafb_mmio_read(VDMA_CSR0);
        viafb_mmio_write(VDMA_CSR0, VDMA_C_ENABLE|VDMA_C_START);
        spin_unlock_irqrestore(&global_dev.reg_lock, flags);
        /*
         * Now we just wait until the interrupt handler says
         * we're done.
         */
        wait_for_completion_interruptible(&viafb_dma_completion);
        viafb_mmio_write(VDMA_MR0, 0); /* Reset int enable */
        mutex_unlock(&viafb_dma_lock);
}
EXPORT_SYMBOL_GPL(viafb_dma_copy_out);
#endif

/*
 * Do a scatter/gather DMA copy from FB memory.  You must have done
 * a successful call to viafb_request_dma() first.
 */
int viafb_dma_copy_out_sg(unsigned int offset, struct scatterlist *sg, int nsg)
{
        struct viafb_vx855_dma_descr *descr;
        void *descrpages;
        dma_addr_t descr_handle;
        unsigned long flags;
        int i;
        struct scatterlist *sgentry;
        dma_addr_t nextdesc;

        /*
         * Get a place to put the descriptors.
         */
        descrpages = dma_alloc_coherent(&global_dev.pdev->dev,
                        nsg*sizeof(struct viafb_vx855_dma_descr),
                        &descr_handle, GFP_KERNEL);
        if (descrpages == NULL) {
                dev_err(&global_dev.pdev->dev, "Unable to get descr page.\n");
                return -ENOMEM;
        }
        mutex_lock(&viafb_dma_lock);
        /*
         * Fill them in.
         */
        descr = descrpages;
        nextdesc = descr_handle + sizeof(struct viafb_vx855_dma_descr);
        for_each_sg(sg, sgentry, nsg, i) {
                dma_addr_t paddr = sg_dma_address(sgentry);
                descr->addr_low = paddr & 0xfffffff0;
                descr->addr_high = ((u64) paddr >> 32) & 0x0fff;
                descr->fb_offset = offset;
                descr->seg_size = sg_dma_len(sgentry) >> 4;
                descr->tile_mode = 0;
                descr->next_desc_low = (nextdesc&0xfffffff0) | VIAFB_DMA_MAGIC;
                descr->next_desc_high = ((u64) nextdesc >> 32) & 0x0fff;
                descr->pad = 0xffffffff;  /* VIA driver does this */
                offset += sg_dma_len(sgentry);
                nextdesc += sizeof(struct viafb_vx855_dma_descr);
                descr++;
        }
        descr[-1].next_desc_low = VIAFB_DMA_FINAL_SEGMENT|VIAFB_DMA_MAGIC;
        /*
         * Program the engine.
         */
        spin_lock_irqsave(&global_dev.reg_lock, flags);
        init_completion(&viafb_dma_completion);
        viafb_mmio_write(VDMA_DQWCR0, 0);
        viafb_mmio_write(VDMA_CSR0, VDMA_C_ENABLE|VDMA_C_DONE);
        viafb_mmio_write(VDMA_MR0, VDMA_MR_TDIE | VDMA_MR_CHAIN);
        viafb_mmio_write(VDMA_DPRL0, descr_handle | VIAFB_DMA_MAGIC);
        viafb_mmio_write(VDMA_DPRH0,
                        (((u64)descr_handle >> 32) & 0x0fff) | 0xf0000);
        (void) viafb_mmio_read(VDMA_CSR0);
        viafb_mmio_write(VDMA_CSR0, VDMA_C_ENABLE|VDMA_C_START);
        spin_unlock_irqrestore(&global_dev.reg_lock, flags);
        /*
         * Now we just wait until the interrupt handler says
         * we're done.  Except that, actually, we need to wait a little
         * longer: the interrupts seem to jump the gun a little and we
         * get corrupted frames sometimes.
         */
        wait_for_completion_timeout(&viafb_dma_completion, 1);
        msleep(1);
        if ((viafb_mmio_read(VDMA_CSR0)&VDMA_C_DONE) == 0)
                printk(KERN_ERR "VIA DMA timeout!\n");
        /*
         * Clean up and we're done.
         */
        viafb_mmio_write(VDMA_CSR0, VDMA_C_DONE);
        viafb_mmio_write(VDMA_MR0, 0); /* Reset int enable */
        mutex_unlock(&viafb_dma_lock);
        dma_free_coherent(&global_dev.pdev->dev,
                        nsg*sizeof(struct viafb_vx855_dma_descr), descrpages,
                        descr_handle);
        return 0;
}
EXPORT_SYMBOL_GPL(viafb_dma_copy_out_sg);
#endif /* CONFIG_VIDEO_VIA_CAMERA */

/* ---------------------------------------------------------------------- */
/*
 * Figure out how big our framebuffer memory is.  Kind of ugly,
 * but evidently we can't trust the information found in the
 * fbdev configuration area.
 */
static u16 via_function3[] = {
        CLE266_FUNCTION3, KM400_FUNCTION3, CN400_FUNCTION3, CN700_FUNCTION3,
        CX700_FUNCTION3, KM800_FUNCTION3, KM890_FUNCTION3, P4M890_FUNCTION3,
        P4M900_FUNCTION3, VX800_FUNCTION3, VX855_FUNCTION3,
};

/* Get the BIOS-configured framebuffer size from PCI configuration space
 * of function 3 in the respective chipset */
static int viafb_get_fb_size_from_pci(int chip_type)
{
        int i;
        u8 offset = 0;
        u32 FBSize;
        u32 VideoMemSize;

        /* search for the "FUNCTION3" device in this chipset */
        for (i = 0; i < ARRAY_SIZE(via_function3); i++) {
                struct pci_dev *pdev;

                pdev = pci_get_device(PCI_VENDOR_ID_VIA, via_function3[i],
                                      NULL);
                if (!pdev)
                        continue;

                DEBUG_MSG(KERN_INFO "Device ID = %x\n", pdev->device);

                switch (pdev->device) {
                case CLE266_FUNCTION3:
                case KM400_FUNCTION3:
                        offset = 0xE0;
                        break;
                case CN400_FUNCTION3:
                case CN700_FUNCTION3:
                case CX700_FUNCTION3:
                case KM800_FUNCTION3:
                case KM890_FUNCTION3:
                case P4M890_FUNCTION3:
                case P4M900_FUNCTION3:
                case VX800_FUNCTION3:
                case VX855_FUNCTION3:
                /*case CN750_FUNCTION3: */
                        offset = 0xA0;
                        break;
                }

                if (!offset)
                        break;

                pci_read_config_dword(pdev, offset, &FBSize);
                pci_dev_put(pdev);
        }

        if (!offset) {
                printk(KERN_ERR "cannot determine framebuffer size\n");
                return -EIO;
        }

        FBSize = FBSize & 0x00007000;
        DEBUG_MSG(KERN_INFO "FB Size = %x\n", FBSize);

        if (chip_type < UNICHROME_CX700) {
                switch (FBSize) {
                case 0x00004000:
                        VideoMemSize = (16 << 20);      /*16M */
                        break;

                case 0x00005000:
                        VideoMemSize = (32 << 20);      /*32M */
                        break;

                case 0x00006000:
                        VideoMemSize = (64 << 20);      /*64M */
                        break;

                default:
                        VideoMemSize = (32 << 20);      /*32M */
                        break;
                }
        } else {
                switch (FBSize) {
                case 0x00001000:
                        VideoMemSize = (8 << 20);       /*8M */
                        break;

                case 0x00002000:
                        VideoMemSize = (16 << 20);      /*16M */
                        break;

                case 0x00003000:
                        VideoMemSize = (32 << 20);      /*32M */
                        break;

                case 0x00004000:
                        VideoMemSize = (64 << 20);      /*64M */
                        break;

                case 0x00005000:
                        VideoMemSize = (128 << 20);     /*128M */
                        break;

                case 0x00006000:
                        VideoMemSize = (256 << 20);     /*256M */
                        break;

                case 0x00007000:        /* Only on VX855/875 */
                        VideoMemSize = (512 << 20);     /*512M */
                        break;

                default:
                        VideoMemSize = (32 << 20);      /*32M */
                        break;
                }
        }

        return VideoMemSize;
}


/*
 * Figure out and map our MMIO regions.
 */
static int __devinit via_pci_setup_mmio(struct viafb_dev *vdev)
{
        int ret;
        /*
         * Hook up to the device registers.  Note that we soldier
         * on if it fails; the framebuffer can operate (without
         * acceleration) without this region.
         */
        vdev->engine_start = pci_resource_start(vdev->pdev, 1);
        vdev->engine_len = pci_resource_len(vdev->pdev, 1);
        vdev->engine_mmio = ioremap_nocache(vdev->engine_start,
                        vdev->engine_len);
        if (vdev->engine_mmio == NULL)
                dev_err(&vdev->pdev->dev,
                                "Unable to map engine MMIO; operation will be "
                                "slow and crippled.\n");
        /*
         * Map in framebuffer memory.  For now, failure here is
         * fatal.  Unfortunately, in the absence of significant
         * vmalloc space, failure here is also entirely plausible.
         * Eventually we want to move away from mapping this
         * entire region.
         */
        vdev->fbmem_start = pci_resource_start(vdev->pdev, 0);
        ret = vdev->fbmem_len = viafb_get_fb_size_from_pci(vdev->chip_type);
        if (ret < 0)
                goto out_unmap;
        vdev->fbmem = ioremap_nocache(vdev->fbmem_start, vdev->fbmem_len);
        if (vdev->fbmem == NULL) {
                ret = -ENOMEM;
                goto out_unmap;
        }
        return 0;
out_unmap:
        iounmap(vdev->engine_mmio);
        return ret;
}

static void via_pci_teardown_mmio(struct viafb_dev *vdev)
{
        iounmap(vdev->fbmem);
        iounmap(vdev->engine_mmio);
}

/*
 * Create our subsidiary devices.
 */
static struct viafb_subdev_info {
        char *name;
        struct platform_device *platdev;
} viafb_subdevs[] = {
        {
                .name = "viafb-gpio",
        },
        {
                .name = "viafb-i2c",
        },
#if defined(CONFIG_VIDEO_VIA_CAMERA) || defined(CONFIG_VIDEO_VIA_CAMERA_MODULE)
        {
                .name = "viafb-camera",
        },
#endif
};
#define N_SUBDEVS ARRAY_SIZE(viafb_subdevs)

static int __devinit via_create_subdev(struct viafb_dev *vdev,
                struct viafb_subdev_info *info)
{
        int ret;

        info->platdev = platform_device_alloc(info->name, -1);
        if (!info->platdev) {
                dev_err(&vdev->pdev->dev, "Unable to allocate pdev %s\n",
                        info->name);
                return -ENOMEM;
        }
        info->platdev->dev.parent = &vdev->pdev->dev;
        info->platdev->dev.platform_data = vdev;
        ret = platform_device_add(info->platdev);
        if (ret) {
                dev_err(&vdev->pdev->dev, "Unable to add pdev %s\n",
                                info->name);
                platform_device_put(info->platdev);
                info->platdev = NULL;
        }
        return ret;
}

static int __devinit via_setup_subdevs(struct viafb_dev *vdev)
{
        int i;

        /*
         * Ignore return values.  Even if some of the devices
         * fail to be created, we'll still be able to use some
         * of the rest.
         */
        for (i = 0; i < N_SUBDEVS; i++)
                via_create_subdev(vdev, viafb_subdevs + i);
        return 0;
}

static void via_teardown_subdevs(void)
{
        int i;

        for (i = 0; i < N_SUBDEVS; i++)
                if (viafb_subdevs[i].platdev) {
                        viafb_subdevs[i].platdev->dev.platform_data = NULL;
                        platform_device_unregister(viafb_subdevs[i].platdev);
                }
}


static int __devinit via_pci_probe(struct pci_dev *pdev,
                const struct pci_device_id *ent)
{
        int ret;

        ret = pci_enable_device(pdev);
        if (ret)
                return ret;
        /*
         * Global device initialization.
         */
        memset(&global_dev, 0, sizeof(global_dev));
        global_dev.pdev = pdev;
        global_dev.chip_type = ent->driver_data;
        global_dev.port_cfg = adap_configs;
        spin_lock_init(&global_dev.reg_lock);
        ret = via_pci_setup_mmio(&global_dev);
        if (ret)
                goto out_disable;
        /*
         * Set up interrupts and create our subdevices.  Continue even if
         * some things fail.
         */
        viafb_int_init();
        via_setup_subdevs(&global_dev);
        /*
         * Set up the framebuffer device
         */
        ret = via_fb_pci_probe(&global_dev);
        if (ret)
                goto out_subdevs;
        return 0;

out_subdevs:
        via_teardown_subdevs();
        via_pci_teardown_mmio(&global_dev);
out_disable:
        pci_disable_device(pdev);
        return ret;
}

static void __devexit via_pci_remove(struct pci_dev *pdev)
{
        via_teardown_subdevs();
        via_fb_pci_remove(pdev);
        via_pci_teardown_mmio(&global_dev);
        pci_disable_device(pdev);
}


static struct pci_device_id via_pci_table[] __devinitdata = {
        { PCI_DEVICE(PCI_VENDOR_ID_VIA, UNICHROME_CLE266_DID),
          .driver_data = UNICHROME_CLE266 },
        { PCI_DEVICE(PCI_VENDOR_ID_VIA, UNICHROME_K400_DID),
          .driver_data = UNICHROME_K400 },
        { PCI_DEVICE(PCI_VENDOR_ID_VIA, UNICHROME_K800_DID),
          .driver_data = UNICHROME_K800 },
        { PCI_DEVICE(PCI_VENDOR_ID_VIA, UNICHROME_PM800_DID),
          .driver_data = UNICHROME_PM800 },
        { PCI_DEVICE(PCI_VENDOR_ID_VIA, UNICHROME_CN700_DID),
          .driver_data = UNICHROME_CN700 },
        { PCI_DEVICE(PCI_VENDOR_ID_VIA, UNICHROME_CX700_DID),
          .driver_data = UNICHROME_CX700 },
        { PCI_DEVICE(PCI_VENDOR_ID_VIA, UNICHROME_CN750_DID),
          .driver_data = UNICHROME_CN750 },
        { PCI_DEVICE(PCI_VENDOR_ID_VIA, UNICHROME_K8M890_DID),
          .driver_data = UNICHROME_K8M890 },
        { PCI_DEVICE(PCI_VENDOR_ID_VIA, UNICHROME_P4M890_DID),
          .driver_data = UNICHROME_P4M890 },
        { PCI_DEVICE(PCI_VENDOR_ID_VIA, UNICHROME_P4M900_DID),
          .driver_data = UNICHROME_P4M900 },
        { PCI_DEVICE(PCI_VENDOR_ID_VIA, UNICHROME_VX800_DID),
          .driver_data = UNICHROME_VX800 },
        { PCI_DEVICE(PCI_VENDOR_ID_VIA, UNICHROME_VX855_DID),
          .driver_data = UNICHROME_VX855 },
        { }
};
MODULE_DEVICE_TABLE(pci, via_pci_table);

static struct pci_driver via_driver = {
        .name           = "viafb",
        .id_table       = via_pci_table,
        .probe          = via_pci_probe,
        .remove         = __devexit_p(via_pci_remove),
};

static int __init via_core_init(void)
{
        int ret;

        ret = viafb_init();
        if (ret)
                return ret;
        viafb_i2c_init();
        viafb_gpio_init();
        return pci_register_driver(&via_driver);
}

static void __exit via_core_exit(void)
{
        pci_unregister_driver(&via_driver);
        viafb_gpio_exit();
        viafb_i2c_exit();
        viafb_exit();
}

module_init(via_core_init);
module_exit(via_core_exit);