From mboxrd@z Thu Jan 1 00:00:00 1970 From: mporter@linaro.org (Matt Porter) Date: Thu, 15 May 2014 15:19:08 -0400 Subject: [PATCH v3 RESEND 2/5] ARM: add SMP support for Broadcom mobile SoCs In-Reply-To: <5375049C.40104@linaro.org> References: <1400176691-26058-1-git-send-email-elder@linaro.org> <1400176691-26058-3-git-send-email-elder@linaro.org> <5375049C.40104@linaro.org> Message-ID: <20140515191908.GO32082@beef> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, May 15, 2014 at 01:17:00PM -0500, Alex Elder wrote: > On 05/15/2014 01:03 PM, Florian Fainelli wrote: > > Hi Alex, > > > > 2014-05-15 10:58 GMT-07:00 Alex Elder : > >> This patch adds SMP support for BCM281XX and BCM21664 family SoCs. > >> > >> This feature is controlled with a distinct config option such that a > >> SMP-enabled multi-v7 binary can be configured to run these SoCs in > >> uniprocessor mode. Since this SMP functionality is used for > >> multiple Broadcom mobile chip families the config option is called > >> ARCH_BCM_MOBILE_SMP (for lack of a better name). > >> > >> On SoCs of this type, the secondary core is not held in reset on > >> power-on. Instead it loops in a ROM-based holding pen. To release > >> it, one must write into a special register a jump address whose > >> low-order bits have been replaced with a secondary core's id, then > >> trigger an event with SEV. On receipt of an event, the ROM code > >> will examine the register's contents, and if the low-order bits > >> match its cpu id, it will clear them and write the value back to the > >> register just prior to jumping to the address specified. > >> > >> The location of the special register is defined in the device tree > >> using a "secondary-boot-reg" property in a node whose "enable-method" > >> matches. > >> > >> Derived from code originally provided by Ray Jui > >> > >> Signed-off-by: Alex Elder > >> --- > >> arch/arm/mach-bcm/Kconfig | 18 +++- > >> arch/arm/mach-bcm/Makefile | 3 + > >> arch/arm/mach-bcm/platsmp.c | 201 ++++++++++++++++++++++++++++++++++++++++++++ > > > > Could we make that name a little bit more specific to the mobile SoCs? > > Sure. I thought about that but naming stuff here has been a sort > of ongoing struggle... "Kona" made some sense, in some cases, > but it's not perfect. Simlar with "mobile." > > I'll propose "kona_smp.c". OK with you? Unless I get a better > suggestion I'll plan to go with that next time around. Works for me. -Matt