From mboxrd@z Thu Jan 1 00:00:00 1970 From: sudeep.holla@arm.com (Sudeep Holla) Date: Wed, 10 Sep 2014 14:45:21 +0100 Subject: ARM bigendian cpuhotplug In-Reply-To: References: Message-ID: <541055F1.2060604@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 10/09/14 13:59, Hemanth Kumar wrote: >> Are you referring to ARM Vexpress platform with TC2/CA15_A7 card ? >> If yes, idle doesn't work with CONFIG_MTD_CFI irrespective of >> endianness, it's platform limitation. > >> Regards, >> Sudeep > > > Thanks for the reply what is the hardware limitation for this card (VE > CA-15_A7) when we enable CONFIG_MTD_CFI > The cpu resume path should ideal be on some sram or on-chip memory, but on TC2 we use the NOR flash @0x0. When you enable NOR flash in Linux, you can't expect it to be in read-mode always as other cpus might put the NOR device is any mode based on its interaction. As a result when a suspended cpu resumes it might not find the resume code if NOR was not in read mode resulting in unpredicted behaviour. As I said before it's purely a platform firmware limitation. Regards, Sudeep