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| author | Clemens Ladisch <clemens@ladisch.de> | 2010-06-10 08:35:06 +0200 |
|---|---|---|
| committer | Clemens Ladisch <clemens@ladisch.de> | 2010-06-10 08:35:06 +0200 |
| commit | a1a1132bd83d0aea51d4f19be4b4a58a064a0131 (patch) | |
| tree | 93352d6aa9fd8eaa0521fbeb65853cd9f485666e /drivers/firewire/ohci.c | |
| parent | 27a2329f8235d6ce637463f5d83e98d760ef006e (diff) | |
| download | lwn-a1a1132bd83d0aea51d4f19be4b4a58a064a0131.tar.gz lwn-a1a1132bd83d0aea51d4f19be4b4a58a064a0131.zip | |
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 <clemens@ladisch.de>
Diffstat (limited to 'drivers/firewire/ohci.c')
| -rw-r--r-- | drivers/firewire/ohci.c | 27 |
1 files changed, 27 insertions, 0 deletions
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, |