From mboxrd@z Thu Jan 1 00:00:00 1970 From: marc.zyngier@arm.com (Marc Zyngier) Date: Wed, 24 Apr 2013 14:52:35 +0100 Subject: [PATCH v3 31/32] arm64: KVM: userspace API documentation In-Reply-To: <20130423230252.GO20569@gmail.com> References: <1365437854-30214-1-git-send-email-marc.zyngier@arm.com> <1365437854-30214-32-git-send-email-marc.zyngier@arm.com> <20130423230252.GO20569@gmail.com> Message-ID: <5177E3A3.4000600@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 24/04/13 00:02, Christoffer Dall wrote: > On Mon, Apr 08, 2013 at 05:17:33PM +0100, Marc Zyngier wrote: >> Unsurprisingly, the arm64 userspace API is extremely similar to >> the 32bit one, the only significant difference being the ONE_REG >> register mapping. >> >> Signed-off-by: Marc Zyngier [...] >> + >> +arm64 registers are mapped using the lower 32 bits. The upper 16 of >> +that is the register group type, or coprocessor number: >> + >> +arm64 core/FP-SIMD registers have the following id bit patterns: >> + 0x6002 0000 0010 >> + >> +arm64 CCSIDR registers are demultiplexed by CSSELR value: >> + 0x6002 0000 0011 00 >> + >> +arm64 system registers have the following id bit patterns: >> + 0x6002 0000 0013 >> + > > I think these size encodings are 4 bits off, and not accurate for for > the core registers, which have variable sizes, which should be indicated > here (unless you decide for a separate category as per my other > comment). Indeed you're right, they're completely wrong. I realized that after your 32bit patch fixing the same thing... Thanks, M. -- Jazz is not dead. It just smells funny...