From 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 Mon Sep 17 00:00:00 2001 From: Yunhong Jiang Date: Tue, 4 Aug 2015 12:17:53 -0700 Subject: Add the rt linux 4.1.3-rt3 as base Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang --- kernel/drivers/bcma/README | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) create mode 100644 kernel/drivers/bcma/README (limited to 'kernel/drivers/bcma/README') diff --git a/kernel/drivers/bcma/README b/kernel/drivers/bcma/README new file mode 100644 index 000000000..f7e7ce46c --- /dev/null +++ b/kernel/drivers/bcma/README @@ -0,0 +1,19 @@ +Broadcom introduced new bus as replacement for older SSB. It is based on AMBA, +however from programming point of view there is nothing AMBA specific we use. + +Standard AMBA drivers are platform specific, have hardcoded addresses and use +AMBA standard fields like CID and PID. + +In case of Broadcom's cards every device consists of: +1) Broadcom specific AMBA device. It is put on AMBA bus, but can not be treated + as standard AMBA device. Reading it's CID or PID can cause machine lockup. +2) AMBA standard devices called ports or wrappers. They have CIDs (AMBA_CID) + and PIDs (0x103BB369), but we do not use that info for anything. One of that + devices is used for managing Broadcom specific core. + +Addresses of AMBA devices are not hardcoded in driver and have to be read from +EPROM. + +In this situation we decided to introduce separated bus. It can contain up to +16 devices identified by Broadcom specific fields: manufacturer, id, revision +and class. -- cgit 1.2.3-korg