From a1a1132bd83d0aea51d4f19be4b4a58a064a0131 Mon Sep 17 00:00:00 2001 From: Clemens Ladisch Date: Thu, 10 Jun 2010 08:35:06 +0200 Subject: [PATCH] firewire: add CSR PRIORITY_BUDGET support If supported by the OHCI controller, implement the PRIORITY_BUDGET register, which is required for nodes that can use asynchronous priority arbitration. To allow the core to determine what features the lowlevel device supports, add a new card driver callback. Signed-off-by: Clemens Ladisch --- drivers/firewire/core-transaction.c | 14 ++++++++++++++ drivers/firewire/core.h | 4 ++++ drivers/firewire/ohci.c | 27 +++++++++++++++++++++++++++ include/linux/firewire.h | 1 + 4 files changed, 46 insertions(+) diff --git a/drivers/firewire/core-transaction.c b/drivers/firewire/core-transaction.c index 8146133818dc..a61eb3fb9573 100644 --- a/drivers/firewire/core-transaction.c +++ b/drivers/firewire/core-transaction.c @@ -1126,6 +1126,20 @@ static void handle_registers(struct fw_card *card, struct fw_request *request, rcode = RCODE_TYPE_ERROR; break; + case CSR_PRIORITY_BUDGET: + if (!(card->driver->get_features(card) & + FEATURE_PRIORITY_BUDGET)) + rcode = RCODE_ADDRESS_ERROR; + else if (tcode == TCODE_READ_QUADLET_REQUEST) + *data = cpu_to_be32(card->driver-> + read_csr_reg(card, CSR_PRIORITY_BUDGET)); + else if (tcode == TCODE_WRITE_QUADLET_REQUEST) + card->driver->write_csr_reg(card, CSR_PRIORITY_BUDGET, + be32_to_cpu(*data)); + else + rcode = RCODE_TYPE_ERROR; + break; + case CSR_BROADCAST_CHANNEL: if (tcode == TCODE_READ_QUADLET_REQUEST) *data = cpu_to_be32(card->broadcast_channel); diff --git a/drivers/firewire/core.h b/drivers/firewire/core.h index efcdeb2e31e6..3b8c0f042f49 100644 --- a/drivers/firewire/core.h +++ b/drivers/firewire/core.h @@ -38,6 +38,8 @@ struct fw_packet; #define BROADCAST_CHANNEL_INITIAL (1 << 31 | 31) #define BROADCAST_CHANNEL_VALID (1 << 30) +#define FEATURE_PRIORITY_BUDGET 0x01 + struct fw_card_driver { /* * Enable the given card with the given initial config rom. @@ -78,6 +80,8 @@ struct fw_card_driver { u32 (*read_csr_reg)(struct fw_card *card, int csr_offset); void (*write_csr_reg)(struct fw_card *card, int csr_offset, u32 value); + unsigned int (*get_features)(struct fw_card *card); + struct fw_iso_context * (*allocate_iso_context)(struct fw_card *card, int type, int channel, size_t header_size); diff --git a/drivers/firewire/ohci.c b/drivers/firewire/ohci.c index 9c588fd01250..0e5413531785 100644 --- a/drivers/firewire/ohci.c +++ b/drivers/firewire/ohci.c @@ -170,6 +170,7 @@ struct fw_ohci { int generation; int request_generation; /* for timestamping incoming requests */ unsigned quirks; + unsigned int pri_req_max; u32 bus_time; /* @@ -1738,6 +1739,11 @@ static int ohci_enable(struct fw_card *card, reg_write(ohci, OHCI1394_IsochronousCycleTimer, seconds << 25); ohci->bus_time = seconds & ~0x3f; + /* Get implemented bits of the priority arbitration request counter. */ + reg_write(ohci, OHCI1394_FairnessControl, 0x3f); + ohci->pri_req_max = reg_read(ohci, OHCI1394_FairnessControl) & 0x3f; + reg_write(ohci, OHCI1394_FairnessControl, 0); + ar_context_run(&ohci->ar_request_ctx); ar_context_run(&ohci->ar_response_ctx); @@ -2028,6 +2034,10 @@ static u32 ohci_read_csr_reg(struct fw_card *card, int csr_offset) value = reg_read(ohci, OHCI1394_ATRetries); return (value >> 4) & 0x0ffff00f; + case CSR_PRIORITY_BUDGET: + return (reg_read(ohci, OHCI1394_FairnessControl) & 0x3f) | + (ohci->pri_req_max << 8); + default: WARN_ON(1); return 0; @@ -2065,12 +2075,28 @@ static void ohci_write_csr_reg(struct fw_card *card, int csr_offset, u32 value) flush_writes(ohci); break; + case CSR_PRIORITY_BUDGET: + reg_write(ohci, OHCI1394_FairnessControl, value & 0x3f); + flush_writes(ohci); + break; + default: WARN_ON(1); break; } } +static unsigned int ohci_get_features(struct fw_card *card) +{ + struct fw_ohci *ohci = fw_ohci(card); + unsigned int features = 0; + + if (ohci->pri_req_max != 0) + features |= FEATURE_PRIORITY_BUDGET; + + return features; +} + static void copy_iso_headers(struct iso_context *ctx, void *p) { int i = ctx->header_length; @@ -2510,6 +2536,7 @@ static const struct fw_card_driver ohci_driver = { .enable_phys_dma = ohci_enable_phys_dma, .read_csr_reg = ohci_read_csr_reg, .write_csr_reg = ohci_write_csr_reg, + .get_features = ohci_get_features, .allocate_iso_context = ohci_allocate_iso_context, .free_iso_context = ohci_free_iso_context, diff --git a/include/linux/firewire.h b/include/linux/firewire.h index cdf8213c68ca..a50377d91254 100644 --- a/include/linux/firewire.h +++ b/include/linux/firewire.h @@ -32,6 +32,7 @@ #define CSR_CYCLE_TIME 0x200 #define CSR_BUS_TIME 0x204 #define CSR_BUSY_TIMEOUT 0x210 +#define CSR_PRIORITY_BUDGET 0x218 #define CSR_BUS_MANAGER_ID 0x21c #define CSR_BANDWIDTH_AVAILABLE 0x220 #define CSR_CHANNELS_AVAILABLE 0x224 -- 2.30.2