From ace9429bb58fd418f0c81d4c2835699bddf6bde6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:27:49 +0200 Subject: Adding upstream version 6.6.15. Signed-off-by: Daniel Baumann --- drivers/firewire/core-iso.c | 379 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 379 insertions(+) create mode 100644 drivers/firewire/core-iso.c (limited to 'drivers/firewire/core-iso.c') diff --git a/drivers/firewire/core-iso.c b/drivers/firewire/core-iso.c new file mode 100644 index 0000000000..af70e74f9a --- /dev/null +++ b/drivers/firewire/core-iso.c @@ -0,0 +1,379 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Isochronous I/O functionality: + * - Isochronous DMA context management + * - Isochronous bus resource management (channels, bandwidth), client side + * + * Copyright (C) 2006 Kristian Hoegsberg + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +#include "core.h" + +/* + * Isochronous DMA context management + */ + +int fw_iso_buffer_alloc(struct fw_iso_buffer *buffer, int page_count) +{ + int i; + + buffer->page_count = 0; + buffer->page_count_mapped = 0; + buffer->pages = kmalloc_array(page_count, sizeof(buffer->pages[0]), + GFP_KERNEL); + if (buffer->pages == NULL) + return -ENOMEM; + + for (i = 0; i < page_count; i++) { + buffer->pages[i] = alloc_page(GFP_KERNEL | GFP_DMA32 | __GFP_ZERO); + if (buffer->pages[i] == NULL) + break; + } + buffer->page_count = i; + if (i < page_count) { + fw_iso_buffer_destroy(buffer, NULL); + return -ENOMEM; + } + + return 0; +} + +int fw_iso_buffer_map_dma(struct fw_iso_buffer *buffer, struct fw_card *card, + enum dma_data_direction direction) +{ + dma_addr_t address; + int i; + + buffer->direction = direction; + + for (i = 0; i < buffer->page_count; i++) { + address = dma_map_page(card->device, buffer->pages[i], + 0, PAGE_SIZE, direction); + if (dma_mapping_error(card->device, address)) + break; + + set_page_private(buffer->pages[i], address); + } + buffer->page_count_mapped = i; + if (i < buffer->page_count) + return -ENOMEM; + + return 0; +} + +int fw_iso_buffer_init(struct fw_iso_buffer *buffer, struct fw_card *card, + int page_count, enum dma_data_direction direction) +{ + int ret; + + ret = fw_iso_buffer_alloc(buffer, page_count); + if (ret < 0) + return ret; + + ret = fw_iso_buffer_map_dma(buffer, card, direction); + if (ret < 0) + fw_iso_buffer_destroy(buffer, card); + + return ret; +} +EXPORT_SYMBOL(fw_iso_buffer_init); + +void fw_iso_buffer_destroy(struct fw_iso_buffer *buffer, + struct fw_card *card) +{ + int i; + dma_addr_t address; + + for (i = 0; i < buffer->page_count_mapped; i++) { + address = page_private(buffer->pages[i]); + dma_unmap_page(card->device, address, + PAGE_SIZE, buffer->direction); + } + for (i = 0; i < buffer->page_count; i++) + __free_page(buffer->pages[i]); + + kfree(buffer->pages); + buffer->pages = NULL; + buffer->page_count = 0; + buffer->page_count_mapped = 0; +} +EXPORT_SYMBOL(fw_iso_buffer_destroy); + +/* Convert DMA address to offset into virtually contiguous buffer. */ +size_t fw_iso_buffer_lookup(struct fw_iso_buffer *buffer, dma_addr_t completed) +{ + size_t i; + dma_addr_t address; + ssize_t offset; + + for (i = 0; i < buffer->page_count; i++) { + address = page_private(buffer->pages[i]); + offset = (ssize_t)completed - (ssize_t)address; + if (offset > 0 && offset <= PAGE_SIZE) + return (i << PAGE_SHIFT) + offset; + } + + return 0; +} + +struct fw_iso_context *fw_iso_context_create(struct fw_card *card, + int type, int channel, int speed, size_t header_size, + fw_iso_callback_t callback, void *callback_data) +{ + struct fw_iso_context *ctx; + + ctx = card->driver->allocate_iso_context(card, + type, channel, header_size); + if (IS_ERR(ctx)) + return ctx; + + ctx->card = card; + ctx->type = type; + ctx->channel = channel; + ctx->speed = speed; + ctx->header_size = header_size; + ctx->callback.sc = callback; + ctx->callback_data = callback_data; + + return ctx; +} +EXPORT_SYMBOL(fw_iso_context_create); + +void fw_iso_context_destroy(struct fw_iso_context *ctx) +{ + ctx->card->driver->free_iso_context(ctx); +} +EXPORT_SYMBOL(fw_iso_context_destroy); + +int fw_iso_context_start(struct fw_iso_context *ctx, + int cycle, int sync, int tags) +{ + return ctx->card->driver->start_iso(ctx, cycle, sync, tags); +} +EXPORT_SYMBOL(fw_iso_context_start); + +int fw_iso_context_set_channels(struct fw_iso_context *ctx, u64 *channels) +{ + return ctx->card->driver->set_iso_channels(ctx, channels); +} + +int fw_iso_context_queue(struct fw_iso_context *ctx, + struct fw_iso_packet *packet, + struct fw_iso_buffer *buffer, + unsigned long payload) +{ + return ctx->card->driver->queue_iso(ctx, packet, buffer, payload); +} +EXPORT_SYMBOL(fw_iso_context_queue); + +void fw_iso_context_queue_flush(struct fw_iso_context *ctx) +{ + ctx->card->driver->flush_queue_iso(ctx); +} +EXPORT_SYMBOL(fw_iso_context_queue_flush); + +int fw_iso_context_flush_completions(struct fw_iso_context *ctx) +{ + return ctx->card->driver->flush_iso_completions(ctx); +} +EXPORT_SYMBOL(fw_iso_context_flush_completions); + +int fw_iso_context_stop(struct fw_iso_context *ctx) +{ + return ctx->card->driver->stop_iso(ctx); +} +EXPORT_SYMBOL(fw_iso_context_stop); + +/* + * Isochronous bus resource management (channels, bandwidth), client side + */ + +static int manage_bandwidth(struct fw_card *card, int irm_id, int generation, + int bandwidth, bool allocate) +{ + int try, new, old = allocate ? BANDWIDTH_AVAILABLE_INITIAL : 0; + __be32 data[2]; + + /* + * On a 1394a IRM with low contention, try < 1 is enough. + * On a 1394-1995 IRM, we need at least try < 2. + * Let's just do try < 5. + */ + for (try = 0; try < 5; try++) { + new = allocate ? old - bandwidth : old + bandwidth; + if (new < 0 || new > BANDWIDTH_AVAILABLE_INITIAL) + return -EBUSY; + + data[0] = cpu_to_be32(old); + data[1] = cpu_to_be32(new); + switch (fw_run_transaction(card, TCODE_LOCK_COMPARE_SWAP, + irm_id, generation, SCODE_100, + CSR_REGISTER_BASE + CSR_BANDWIDTH_AVAILABLE, + data, 8)) { + case RCODE_GENERATION: + /* A generation change frees all bandwidth. */ + return allocate ? -EAGAIN : bandwidth; + + case RCODE_COMPLETE: + if (be32_to_cpup(data) == old) + return bandwidth; + + old = be32_to_cpup(data); + /* Fall through. */ + } + } + + return -EIO; +} + +static int manage_channel(struct fw_card *card, int irm_id, int generation, + u32 channels_mask, u64 offset, bool allocate) +{ + __be32 bit, all, old; + __be32 data[2]; + int channel, ret = -EIO, retry = 5; + + old = all = allocate ? cpu_to_be32(~0) : 0; + + for (channel = 0; channel < 32; channel++) { + if (!(channels_mask & 1 << channel)) + continue; + + ret = -EBUSY; + + bit = cpu_to_be32(1 << (31 - channel)); + if ((old & bit) != (all & bit)) + continue; + + data[0] = old; + data[1] = old ^ bit; + switch (fw_run_transaction(card, TCODE_LOCK_COMPARE_SWAP, + irm_id, generation, SCODE_100, + offset, data, 8)) { + case RCODE_GENERATION: + /* A generation change frees all channels. */ + return allocate ? -EAGAIN : channel; + + case RCODE_COMPLETE: + if (data[0] == old) + return channel; + + old = data[0]; + + /* Is the IRM 1394a-2000 compliant? */ + if ((data[0] & bit) == (data[1] & bit)) + continue; + + fallthrough; /* It's a 1394-1995 IRM, retry */ + default: + if (retry) { + retry--; + channel--; + } else { + ret = -EIO; + } + } + } + + return ret; +} + +static void deallocate_channel(struct fw_card *card, int irm_id, + int generation, int channel) +{ + u32 mask; + u64 offset; + + mask = channel < 32 ? 1 << channel : 1 << (channel - 32); + offset = channel < 32 ? CSR_REGISTER_BASE + CSR_CHANNELS_AVAILABLE_HI : + CSR_REGISTER_BASE + CSR_CHANNELS_AVAILABLE_LO; + + manage_channel(card, irm_id, generation, mask, offset, false); +} + +/** + * fw_iso_resource_manage() - Allocate or deallocate a channel and/or bandwidth + * @card: card interface for this action + * @generation: bus generation + * @channels_mask: bitmask for channel allocation + * @channel: pointer for returning channel allocation result + * @bandwidth: pointer for returning bandwidth allocation result + * @allocate: whether to allocate (true) or deallocate (false) + * + * In parameters: card, generation, channels_mask, bandwidth, allocate + * Out parameters: channel, bandwidth + * + * This function blocks (sleeps) during communication with the IRM. + * + * Allocates or deallocates at most one channel out of channels_mask. + * channels_mask is a bitfield with MSB for channel 63 and LSB for channel 0. + * (Note, the IRM's CHANNELS_AVAILABLE is a big-endian bitfield with MSB for + * channel 0 and LSB for channel 63.) + * Allocates or deallocates as many bandwidth allocation units as specified. + * + * Returns channel < 0 if no channel was allocated or deallocated. + * Returns bandwidth = 0 if no bandwidth was allocated or deallocated. + * + * If generation is stale, deallocations succeed but allocations fail with + * channel = -EAGAIN. + * + * If channel allocation fails, no bandwidth will be allocated either. + * If bandwidth allocation fails, no channel will be allocated either. + * But deallocations of channel and bandwidth are tried independently + * of each other's success. + */ +void fw_iso_resource_manage(struct fw_card *card, int generation, + u64 channels_mask, int *channel, int *bandwidth, + bool allocate) +{ + u32 channels_hi = channels_mask; /* channels 31...0 */ + u32 channels_lo = channels_mask >> 32; /* channels 63...32 */ + int irm_id, ret, c = -EINVAL; + + spin_lock_irq(&card->lock); + irm_id = card->irm_node->node_id; + spin_unlock_irq(&card->lock); + + if (channels_hi) + c = manage_channel(card, irm_id, generation, channels_hi, + CSR_REGISTER_BASE + CSR_CHANNELS_AVAILABLE_HI, + allocate); + if (channels_lo && c < 0) { + c = manage_channel(card, irm_id, generation, channels_lo, + CSR_REGISTER_BASE + CSR_CHANNELS_AVAILABLE_LO, + allocate); + if (c >= 0) + c += 32; + } + *channel = c; + + if (allocate && channels_mask != 0 && c < 0) + *bandwidth = 0; + + if (*bandwidth == 0) + return; + + ret = manage_bandwidth(card, irm_id, generation, *bandwidth, allocate); + if (ret < 0) + *bandwidth = 0; + + if (allocate && ret < 0) { + if (c >= 0) + deallocate_channel(card, irm_id, generation, c); + *channel = ret; + } +} +EXPORT_SYMBOL(fw_iso_resource_manage); -- cgit v1.2.3