From 7889b60ee71eafaf50699a154a2455424bb92daa Mon Sep 17 00:00:00 2001 From: Stefan Richter Date: Tue, 10 Mar 2009 21:09:28 +0100 Subject: firewire: core: optimize propagation of BROADCAST_CHANNEL Cache the test result of whether a device implements BROADCAST_CHANNEL. This minimizes traffic on the bus after each bus reset. A majority of devices does not implement BROADCAST_CHANNEL. Remove busy retries; just rely on the hardware to retry requests to busy responders. Remove unnecessary log messages. Rename the flag is_irm to broadcast_channel_allocated to better reflect its meaning. Reset the flag earlier in fw_core_handle_bus_reset. Pass the generation down as a call parameter; that way generation can't be newer than card->broadcast_channel_allocated and device->node_id. Signed-off-by: Stefan Richter --- drivers/firewire/fw-card.c | 85 +++------------------------------------------- 1 file changed, 5 insertions(+), 80 deletions(-) (limited to 'drivers/firewire/fw-card.c') diff --git a/drivers/firewire/fw-card.c b/drivers/firewire/fw-card.c index d63d0ed9e04..8b8c8c22f0f 100644 --- a/drivers/firewire/fw-card.c +++ b/drivers/firewire/fw-card.c @@ -181,83 +181,9 @@ void fw_core_remove_descriptor(struct fw_descriptor *desc) mutex_unlock(&card_mutex); } -#define IRM_RETRIES 2 - -/* - * The abi is set by device_for_each_child(), even though we have no use - * for data, nor do we have a meaningful return value. - */ -int fw_irm_set_broadcast_channel_register(struct device *dev, void *data) +static int set_broadcast_channel(struct device *dev, void *data) { - struct fw_device *d; - int rcode; - int node_id; - int max_speed; - int retries; - int generation; - __be32 regval; - struct fw_card *card; - - d = fw_device(dev); - /* FIXME: do we need locking here? */ - generation = d->generation; - smp_rmb(); /* Ensure generation is at least as old as node_id */ - node_id = d->node_id; - max_speed = d->max_speed; - retries = IRM_RETRIES; - card = d->card; -tryagain_r: - rcode = fw_run_transaction(card, TCODE_READ_QUADLET_REQUEST, - node_id, generation, max_speed, - CSR_REGISTER_BASE + CSR_BROADCAST_CHANNEL, - ®val, 4); - switch (rcode) { - case RCODE_BUSY: - if (retries--) - goto tryagain_r; - fw_notify("node %x read broadcast channel busy\n", - node_id); - return 0; - - default: - fw_notify("node %x read broadcast channel failed %x\n", - node_id, rcode); - return 0; - - case RCODE_COMPLETE: - /* - * Paranoid reporting of nonstandard broadcast channel - * contents goes here - */ - if (regval != cpu_to_be32(BROADCAST_CHANNEL_INITIAL)) - return 0; - break; - } - retries = IRM_RETRIES; - regval = cpu_to_be32(BROADCAST_CHANNEL_INITIAL | - BROADCAST_CHANNEL_VALID); -tryagain_w: - rcode = fw_run_transaction(card, - TCODE_WRITE_QUADLET_REQUEST, node_id, - generation, max_speed, - CSR_REGISTER_BASE + CSR_BROADCAST_CHANNEL, - ®val, 4); - switch (rcode) { - case RCODE_BUSY: - if (retries--) - goto tryagain_w; - fw_notify("node %x write broadcast channel busy\n", - node_id); - return 0; - - default: - fw_notify("node %x write broadcast channel failed %x\n", - node_id, rcode); - return 0; - - case RCODE_COMPLETE: - return 0; - } + fw_device_set_broadcast_channel(fw_device(dev), (long)data); return 0; } @@ -268,9 +194,9 @@ static void allocate_broadcast_channel(struct fw_card *card, int generation) fw_iso_resource_manage(card, generation, 1ULL << 31, &channel, &bandwidth, true); if (channel == 31) { - card->is_irm = true; - device_for_each_child(card->device, NULL, - fw_irm_set_broadcast_channel_register); + card->broadcast_channel_allocated = true; + device_for_each_child(card->device, (void *)(long)generation, + set_broadcast_channel); } } @@ -302,7 +228,6 @@ static void fw_card_bm_work(struct work_struct *work) __be32 lock_data[2]; spin_lock_irqsave(&card->lock, flags); - card->is_irm = false; if (card->local_node == NULL) { spin_unlock_irqrestore(&card->lock, flags); -- cgit v1.2.3