From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by bombadil.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux)) id 1dCkYL-0004va-BD for barebox@lists.infradead.org; Mon, 22 May 2017 10:27:07 +0000 Date: Mon, 22 May 2017 12:26:43 +0200 From: Sascha Hauer Message-ID: <20170522102643.outnjbd4ymnrph5f@pengutronix.de> References: <20170522084930.6072-1-jbe@pengutronix.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20170522084930.6072-1-jbe@pengutronix.de> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: [PATCH] PPC: request a consistent memory layout (part II) To: Juergen Borleis Cc: barebox@lists.infradead.org On Mon, May 22, 2017 at 10:49:30AM +0200, Juergen Borleis wrote: > Using the memory test command will crash barebox, because it may tests the > area where the vector table is located for the PPC architecture. > > On the e300 PPC core the vectors are programmable in their location. > This change checks the used location at run-time and requests the area > to prevent the memory test from overwriting it. > > Signed-off-by: Juergen Borleis > --- > arch/ppc/include/asm/common.h | 1 + > arch/ppc/mach-mpc5xxx/cpu.c | 17 +++++++++++++++++ > arch/ppc/mach-mpc5xxx/start.S | 5 +++++ > 3 files changed, 23 insertions(+) > > diff --git a/arch/ppc/include/asm/common.h b/arch/ppc/include/asm/common.h > index 045817bed..7ea5dacdb 100644 > --- a/arch/ppc/include/asm/common.h > +++ b/arch/ppc/include/asm/common.h > @@ -11,6 +11,7 @@ int cpu_init (void); > > uint get_pvr (void); > uint get_svr (void); > +uint get_msr (void); > > void trap_init (ulong); > > diff --git a/arch/ppc/mach-mpc5xxx/cpu.c b/arch/ppc/mach-mpc5xxx/cpu.c > index ab58967aa..75bb7b9e8 100644 > --- a/arch/ppc/mach-mpc5xxx/cpu.c > +++ b/arch/ppc/mach-mpc5xxx/cpu.c > @@ -61,10 +61,27 @@ int checkcpu (void) > } > > /* ------------------------------------------------------------------------- */ > +static unsigned mpc5125_get_CPU_exception_vector_begin(void) > +{ > + unsigned msr = get_msr(); > + > + if (msr & MSR_IP) > + return 0xfff00000; > + return 0x00000000; > +} > > static int mpc5xxx_reserve_region(void) > { > struct resource *r; > + unsigned exception_vector; > + > + exception_vector = mpc5125_get_CPU_exception_vector_begin(); > + r = request_sdram_region("vector_table", exception_vector, exception_vector + 0x2fff); > + if (r == NULL) { > + pr_err("Failed to request vector_table region at: 0x%08x/0x%08x\n", > + exception_vector, exception_vector + 0x2fff); > + return -EBUSY; > + } I have the feeling that we should actively put the vector table to one of the two locations, so we should implicitly know where it is and not have to test the MSR_IP bit. Also there is no SDRAM at 0xfff00000, right? Requesting SDRAM there will fail every time for a good reason. Sascha -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox