From 2608203daf5f87311c6e5d36e5de5efcb14aab24 Mon Sep 17 00:00:00 2001 From: Clemens Ladisch Date: Mon, 12 Apr 2010 10:35:30 +0200 Subject: firewire: ohci: prevent aliasing of locally handled register addresses We must compute the offset from the CSR register base with the full 48 address bits to prevent matching with addresses whose lower 32 bits happen to be equal with one of the specially handled registers. Signed-off-by: Clemens Ladisch Signed-off-by: Stefan Richter --- drivers/firewire/ohci.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'drivers/firewire/ohci.c') diff --git a/drivers/firewire/ohci.c b/drivers/firewire/ohci.c index e33917bf97d2..82fb2e7e99ef 100644 --- a/drivers/firewire/ohci.c +++ b/drivers/firewire/ohci.c @@ -1198,8 +1198,7 @@ static void handle_local_lock(struct fw_ohci *ohci, static void handle_local_request(struct context *ctx, struct fw_packet *packet) { - u64 offset; - u32 csr; + u64 offset, csr; if (ctx == &ctx->ohci->at_request_ctx) { packet->ack = ACK_PENDING; -- cgit v1.2.3 From e1393667be574807a13bfaf1bb471f5fd1a5287b Mon Sep 17 00:00:00 2001 From: Clemens Ladisch Date: Mon, 12 Apr 2010 10:35:44 +0200 Subject: firewire: ohci: wait for local CSR lock access to finish Add a loop to wait for the controller to finish a locally-initiated CSR lock operation. Google shows some occurrences of the "swap not done yet" message which might indicate that some OHCI controllers are not fast enough to do the lock/swap in the time needed for one PCI access. This also correctly handles the case where the lock operation did not finish, instead of silently returning an uninitialized value. Signed-off-by: Clemens Ladisch Signed-off-by: Stefan Richter --- drivers/firewire/ohci.c | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-) (limited to 'drivers/firewire/ohci.c') diff --git a/drivers/firewire/ohci.c b/drivers/firewire/ohci.c index 82fb2e7e99ef..6e95f8fb56db 100644 --- a/drivers/firewire/ohci.c +++ b/drivers/firewire/ohci.c @@ -1158,7 +1158,7 @@ static void handle_local_lock(struct fw_ohci *ohci, struct fw_packet *packet, u32 csr) { struct fw_packet response; - int tcode, length, ext_tcode, sel; + int tcode, length, ext_tcode, sel, try; __be32 *payload, lock_old; u32 lock_arg, lock_data; @@ -1185,13 +1185,19 @@ static void handle_local_lock(struct fw_ohci *ohci, reg_write(ohci, OHCI1394_CSRCompareData, lock_arg); reg_write(ohci, OHCI1394_CSRControl, sel); - if (reg_read(ohci, OHCI1394_CSRControl) & 0x80000000) - lock_old = cpu_to_be32(reg_read(ohci, OHCI1394_CSRData)); - else - fw_notify("swap not done yet\n"); + for (try = 0; try < 20; try++) + if (reg_read(ohci, OHCI1394_CSRControl) & 0x80000000) { + lock_old = cpu_to_be32(reg_read(ohci, + OHCI1394_CSRData)); + fw_fill_response(&response, packet->header, + RCODE_COMPLETE, + &lock_old, sizeof(lock_old)); + goto out; + } + + fw_error("swap not done (CSR lock timeout)\n"); + fw_fill_response(&response, packet->header, RCODE_BUSY, NULL, 0); - fw_fill_response(&response, packet->header, - RCODE_COMPLETE, &lock_old, sizeof(lock_old)); out: fw_core_handle_response(&ohci->card, &response); } -- cgit v1.2.3