Hi Geert, On Tue, Sep 27, 2016 at 9:37 PM, Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote: > Hi Simon, Magnus, > > On Mon, Aug 22, 2016 at 4:44 PM, Geert Uytterhoeven > <geert+renesas@xxxxxxxxx> wrote: >> This patch series is an attempt to allow booting secondary CPU cores on >> R-Car Gen2 when hardware debug mode is enabled. In this mode, reset >> requests derived from power-shutoff to the AP-system CPU cores must be >> enabled before the AP-system cores first resume from power-shutoff. Else >> resume may fail, causing the system to hang during boot. Currently we >> avoid the hang by prohibiting booting secondary CPU cores when hardware >> debug mode is enabled. >> >> On all R-Car Gen2 SoCs, hardware debug mode is enabled by setting >> MD21=1. On both Koelsch and Lager, this is done by setting mode switch >> SW8-4 to OFF. >> >> Unfortunately the hang is not easy to reproduce: I only saw it (on >> Koelsch) during real cold boot (power off during the night), and even >> then it's not guaranteed to trigger. Pressing the reset button >> afterwards recovers the system, and a subsequent boot will succeed >> (incl. secondary CPU core boot). >> >> This series configures the reset requests as documented in the R-Car >> Gen2 datasheet, and removes the check for MD21 during secondary CPU >> bringup. It was inspired by CPU-specific patches in the BSP by >> Nakamura-san. >> >> This series has been boot-tested on r8a7791/koelsch (both debug mode and >> normal mode), on r8a7790/lager and r8a7793/gose (normal mode only), and >> on r8a7794/alt (normal mode UP only). > > Any comments? > Any objection to applying this series? > > I've been running my Koelsch with MD21=1 since I posted this series, > and it has been included in renesas-drivers since the beginning of September. > > My main motivation to push this is that it removes two more users of > rcar_gen2_read_mode_pins(). After this, the only remaining user is the > clock driver, invoked from rcar_gen2_timer_init(). I have no objections, but I'm curious if the series received enough testing (with debug mode enabled) on earlier R-Car Gen2 platforms like r8a7790/lager? Cheers, / magnus
