diff options
Diffstat (limited to 'drivers/media/pci/cobalt/cobalt-omnitek.c')
| -rw-r--r-- | drivers/media/pci/cobalt/cobalt-omnitek.c | 329 |
1 files changed, 329 insertions, 0 deletions
diff --git a/drivers/media/pci/cobalt/cobalt-omnitek.c b/drivers/media/pci/cobalt/cobalt-omnitek.c new file mode 100644 index 000000000..4c137453e --- /dev/null +++ b/drivers/media/pci/cobalt/cobalt-omnitek.c @@ -0,0 +1,329 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Omnitek Scatter-Gather DMA Controller + * + * Copyright 2012-2015 Cisco Systems, Inc. and/or its affiliates. + * All rights reserved. + */ + +#include <linux/string.h> +#include <linux/io.h> +#include <linux/pci_regs.h> +#include <linux/spinlock.h> + +#include "cobalt-driver.h" +#include "cobalt-omnitek.h" + +/* descriptor */ +#define END_OF_CHAIN (1 << 1) +#define INTERRUPT_ENABLE (1 << 2) +#define WRITE_TO_PCI (1 << 3) +#define READ_FROM_PCI (0 << 3) +#define DESCRIPTOR_FLAG_MSK (END_OF_CHAIN | INTERRUPT_ENABLE | WRITE_TO_PCI) +#define NEXT_ADRS_MSK 0xffffffe0 + +/* control/status register */ +#define ENABLE (1 << 0) +#define START (1 << 1) +#define ABORT (1 << 2) +#define DONE (1 << 4) +#define SG_INTERRUPT (1 << 5) +#define EVENT_INTERRUPT (1 << 6) +#define SCATTER_GATHER_MODE (1 << 8) +#define DISABLE_VIDEO_RESYNC (1 << 9) +#define EVENT_INTERRUPT_ENABLE (1 << 10) +#define DIRECTIONAL_MSK (3 << 16) +#define INPUT_ONLY (0 << 16) +#define OUTPUT_ONLY (1 << 16) +#define BIDIRECTIONAL (2 << 16) +#define DMA_TYPE_MEMORY (0 << 18) +#define DMA_TYPE_FIFO (1 << 18) + +#define BASE (cobalt->bar0) +#define CAPABILITY_HEADER (BASE) +#define CAPABILITY_REGISTER (BASE + 0x04) +#define PCI_64BIT (1 << 8) +#define LOCAL_64BIT (1 << 9) +#define INTERRUPT_STATUS (BASE + 0x08) +#define PCI(c) (BASE + 0x40 + ((c) * 0x40)) +#define SIZE(c) (BASE + 0x58 + ((c) * 0x40)) +#define DESCRIPTOR(c) (BASE + 0x50 + ((c) * 0x40)) +#define CS_REG(c) (BASE + 0x60 + ((c) * 0x40)) +#define BYTES_TRANSFERRED(c) (BASE + 0x64 + ((c) * 0x40)) + + +static char *get_dma_direction(u32 status) +{ + switch (status & DIRECTIONAL_MSK) { + case INPUT_ONLY: return "Input"; + case OUTPUT_ONLY: return "Output"; + case BIDIRECTIONAL: return "Bidirectional"; + } + return ""; +} + +static void show_dma_capability(struct cobalt *cobalt) +{ + u32 header = ioread32(CAPABILITY_HEADER); + u32 capa = ioread32(CAPABILITY_REGISTER); + u32 i; + + cobalt_info("Omnitek DMA capability: ID 0x%02x Version 0x%02x Next 0x%x Size 0x%x\n", + header & 0xff, (header >> 8) & 0xff, + (header >> 16) & 0xffff, (capa >> 24) & 0xff); + + switch ((capa >> 8) & 0x3) { + case 0: + cobalt_info("Omnitek DMA: 32 bits PCIe and Local\n"); + break; + case 1: + cobalt_info("Omnitek DMA: 64 bits PCIe, 32 bits Local\n"); + break; + case 3: + cobalt_info("Omnitek DMA: 64 bits PCIe and Local\n"); + break; + } + + for (i = 0; i < (capa & 0xf); i++) { + u32 status = ioread32(CS_REG(i)); + + cobalt_info("Omnitek DMA channel #%d: %s %s\n", i, + status & DMA_TYPE_FIFO ? "FIFO" : "MEMORY", + get_dma_direction(status)); + } +} + +void omni_sg_dma_start(struct cobalt_stream *s, struct sg_dma_desc_info *desc) +{ + struct cobalt *cobalt = s->cobalt; + + iowrite32((u32)((u64)desc->bus >> 32), DESCRIPTOR(s->dma_channel) + 4); + iowrite32((u32)desc->bus & NEXT_ADRS_MSK, DESCRIPTOR(s->dma_channel)); + iowrite32(ENABLE | SCATTER_GATHER_MODE | START, CS_REG(s->dma_channel)); +} + +bool is_dma_done(struct cobalt_stream *s) +{ + struct cobalt *cobalt = s->cobalt; + + if (ioread32(CS_REG(s->dma_channel)) & DONE) + return true; + + return false; +} + +void omni_sg_dma_abort_channel(struct cobalt_stream *s) +{ + struct cobalt *cobalt = s->cobalt; + + if (is_dma_done(s) == false) + iowrite32(ABORT, CS_REG(s->dma_channel)); +} + +int omni_sg_dma_init(struct cobalt *cobalt) +{ + u32 capa = ioread32(CAPABILITY_REGISTER); + int i; + + cobalt->first_fifo_channel = 0; + cobalt->dma_channels = capa & 0xf; + if (capa & PCI_64BIT) + cobalt->pci_32_bit = false; + else + cobalt->pci_32_bit = true; + + for (i = 0; i < cobalt->dma_channels; i++) { + u32 status = ioread32(CS_REG(i)); + u32 ctrl = ioread32(CS_REG(i)); + + if (!(ctrl & DONE)) + iowrite32(ABORT, CS_REG(i)); + + if (!(status & DMA_TYPE_FIFO)) + cobalt->first_fifo_channel++; + } + show_dma_capability(cobalt); + return 0; +} + +int descriptor_list_create(struct cobalt *cobalt, + struct scatterlist *scatter_list, bool to_pci, unsigned sglen, + unsigned size, unsigned width, unsigned stride, + struct sg_dma_desc_info *desc) +{ + struct sg_dma_descriptor *d = (struct sg_dma_descriptor *)desc->virt; + dma_addr_t next = desc->bus; + unsigned offset = 0; + unsigned copy_bytes = width; + unsigned copied = 0; + bool first = true; + + /* Must be 4-byte aligned */ + WARN_ON(sg_dma_address(scatter_list) & 3); + WARN_ON(size & 3); + WARN_ON(next & 3); + WARN_ON(stride & 3); + WARN_ON(stride < width); + if (width >= stride) + copy_bytes = stride = size; + + while (size) { + dma_addr_t addr = sg_dma_address(scatter_list) + offset; + unsigned bytes; + + if (addr == 0) + return -EFAULT; + if (cobalt->pci_32_bit) { + WARN_ON((u64)addr >> 32); + if ((u64)addr >> 32) + return -EFAULT; + } + + /* PCIe address */ + d->pci_l = addr & 0xffffffff; + /* If dma_addr_t is 32 bits, then addr >> 32 is actually the + equivalent of addr >> 0 in gcc. So must cast to u64. */ + d->pci_h = (u64)addr >> 32; + + /* Sync to start of streaming frame */ + d->local = 0; + d->reserved0 = 0; + + /* Transfer bytes */ + bytes = min(sg_dma_len(scatter_list) - offset, + copy_bytes - copied); + + if (first) { + if (to_pci) + d->local = 0x11111111; + first = false; + if (sglen == 1) { + /* Make sure there are always at least two + * descriptors */ + d->bytes = (bytes / 2) & ~3; + d->reserved1 = 0; + size -= d->bytes; + copied += d->bytes; + offset += d->bytes; + addr += d->bytes; + next += sizeof(struct sg_dma_descriptor); + d->next_h = (u32)((u64)next >> 32); + d->next_l = (u32)next | + (to_pci ? WRITE_TO_PCI : 0); + bytes -= d->bytes; + d++; + /* PCIe address */ + d->pci_l = addr & 0xffffffff; + /* If dma_addr_t is 32 bits, then addr >> 32 + * is actually the equivalent of addr >> 0 in + * gcc. So must cast to u64. */ + d->pci_h = (u64)addr >> 32; + + /* Sync to start of streaming frame */ + d->local = 0; + d->reserved0 = 0; + } + } + + d->bytes = bytes; + d->reserved1 = 0; + size -= bytes; + copied += bytes; + offset += bytes; + + if (copied == copy_bytes) { + while (copied < stride) { + bytes = min(sg_dma_len(scatter_list) - offset, + stride - copied); + copied += bytes; + offset += bytes; + size -= bytes; + if (sg_dma_len(scatter_list) == offset) { + offset = 0; + scatter_list = sg_next(scatter_list); + } + } + copied = 0; + } else { + offset = 0; + scatter_list = sg_next(scatter_list); + } + + /* Next descriptor + control bits */ + next += sizeof(struct sg_dma_descriptor); + if (size == 0) { + /* Loopback to the first descriptor */ + d->next_h = (u32)((u64)desc->bus >> 32); + d->next_l = (u32)desc->bus | + (to_pci ? WRITE_TO_PCI : 0) | INTERRUPT_ENABLE; + if (!to_pci) + d->local = 0x22222222; + desc->last_desc_virt = d; + } else { + d->next_h = (u32)((u64)next >> 32); + d->next_l = (u32)next | (to_pci ? WRITE_TO_PCI : 0); + } + d++; + } + return 0; +} + +void descriptor_list_chain(struct sg_dma_desc_info *this, + struct sg_dma_desc_info *next) +{ + struct sg_dma_descriptor *d = this->last_desc_virt; + u32 direction = d->next_l & WRITE_TO_PCI; + + if (next == NULL) { + d->next_h = 0; + d->next_l = direction | INTERRUPT_ENABLE | END_OF_CHAIN; + } else { + d->next_h = (u32)((u64)next->bus >> 32); + d->next_l = (u32)next->bus | direction | INTERRUPT_ENABLE; + } +} + +void *descriptor_list_allocate(struct sg_dma_desc_info *desc, size_t bytes) +{ + desc->size = bytes; + desc->virt = dma_alloc_coherent(desc->dev, bytes, + &desc->bus, GFP_KERNEL); + return desc->virt; +} + +void descriptor_list_free(struct sg_dma_desc_info *desc) +{ + if (desc->virt) + dma_free_coherent(desc->dev, desc->size, + desc->virt, desc->bus); + desc->virt = NULL; +} + +void descriptor_list_interrupt_enable(struct sg_dma_desc_info *desc) +{ + struct sg_dma_descriptor *d = desc->last_desc_virt; + + d->next_l |= INTERRUPT_ENABLE; +} + +void descriptor_list_interrupt_disable(struct sg_dma_desc_info *desc) +{ + struct sg_dma_descriptor *d = desc->last_desc_virt; + + d->next_l &= ~INTERRUPT_ENABLE; +} + +void descriptor_list_loopback(struct sg_dma_desc_info *desc) +{ + struct sg_dma_descriptor *d = desc->last_desc_virt; + + d->next_h = (u32)((u64)desc->bus >> 32); + d->next_l = (u32)desc->bus | (d->next_l & DESCRIPTOR_FLAG_MSK); +} + +void descriptor_list_end_of_chain(struct sg_dma_desc_info *desc) +{ + struct sg_dma_descriptor *d = desc->last_desc_virt; + + d->next_l |= END_OF_CHAIN; +} |