From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([209.51.188.92]:34464) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gyx1s-0007XU-W5 for qemu-devel@nongnu.org; Wed, 27 Feb 2019 06:05:38 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gyx1r-0008No-3e for qemu-devel@nongnu.org; Wed, 27 Feb 2019 06:05:36 -0500 Received: from mail-wm1-x344.google.com ([2a00:1450:4864:20::344]:40712) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1gyx1q-0007qc-TW for qemu-devel@nongnu.org; Wed, 27 Feb 2019 06:05:35 -0500 Received: by mail-wm1-x344.google.com with SMTP id g20so4411020wmh.5 for ; Wed, 27 Feb 2019 03:04:53 -0800 (PST) References: <20190226193408.23862-1-armbru@redhat.com> <20190226193408.23862-7-armbru@redhat.com> From: Alex =?utf-8?Q?Benn=C3=A9e?= In-reply-to: <20190226193408.23862-7-armbru@redhat.com> Date: Wed, 27 Feb 2019 11:04:50 +0000 Message-ID: <87tvgplcfh.fsf@zen.linaroharston> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH v2 06/11] sam460ex: Don't size flash memory to match backing image List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Markus Armbruster Cc: qemu-devel@nongnu.org, lersek@redhat.com, kwolf@redhat.com, mreitz@redhat.com, qemu-block@nongnu.org, qemu-ppc@nongnu.org, BALATON Zoltan Markus Armbruster writes: > Machine "sam460ex" maps its flash memory at address 0xFFF00000. When > no image is supplied, its size is 1MiB (0x100000), and 512KiB of ROM > get mapped on top of its second half. Else, it's the size of the > image rounded up to the next multiple of 64KiB. > > The rounding is actually useless: pflash_cfi01_realize() fails with > "failed to read the initial flash content" unless it's a no-op. > > I have no idea what happens when the pflash's size exceeds 1MiB. > Useful outcomes seem unlikely. > > I guess memory at the end of the address space remains unmapped when > it's smaller than 1MiB. Again, useful outcomes seem unlikely. > > The physical hardware appears to have 512KiB of flash memory: > https://eu.mouser.com/datasheet/2/268/atmel_AT49BV040B-1180330.pdf > > For now, just set the flash memory size to 1MiB regardless of image > size, and document the mess. > > Cc: BALATON Zoltan > Signed-off-by: Markus Armbruster Reviewed-by: Alex Benn=C3=A9e > --- > hw/ppc/sam460ex.c | 41 ++++++++++++++++++++++++++--------------- > 1 file changed, 26 insertions(+), 15 deletions(-) > > diff --git a/hw/ppc/sam460ex.c b/hw/ppc/sam460ex.c > index 75250d49e4..0c919529f8 100644 > --- a/hw/ppc/sam460ex.c > +++ b/hw/ppc/sam460ex.c > @@ -91,32 +91,43 @@ struct boot_info { > > static int sam460ex_load_uboot(void) > { > + /* > + * This first creates 1MiB of flash memory mapped at the end of > + * the 32-bit address space (0xFFF00000..0xFFFFFFFF). > + * > + * If_PFLASH unit 0 is defined, the flash memory is initialized > + * from that block backend. > + * > + * Else, it's initialized to zero. And then 512KiB of ROM get > + * mapped on top of its second half (0xFFF80000..0xFFFFFFFF), > + * initialized from u-boot-sam460-20100605.bin. > + * > + * This doesn't smell right. > + * > + * The physical hardware appears to have 512KiB flash memory. > + * > + * TODO Figure out what we really need here, and clean this up. > + */ > + > DriveInfo *dinfo; > - BlockBackend *blk =3D NULL; > - hwaddr base =3D FLASH_BASE | ((hwaddr)FLASH_BASE_H << 32); > - long bios_size =3D FLASH_SIZE; > - int fl_sectors; > > dinfo =3D drive_get(IF_PFLASH, 0, 0); > - if (dinfo) { > - blk =3D blk_by_legacy_dinfo(dinfo); > - bios_size =3D blk_getlength(blk); > - } > - fl_sectors =3D (bios_size + 65535) >> 16; > - > - if (!pflash_cfi01_register(base, NULL, "sam460ex.flash", bios_size, > - blk, 64 * KiB, fl_sectors, > + if (!pflash_cfi01_register(FLASH_BASE | ((hwaddr)FLASH_BASE_H << 32), > + NULL, "sam460ex.flash", FLASH_SIZE, > + dinfo ? blk_by_legacy_dinfo(dinfo) : NULL, > + 64 * KiB, FLASH_SIZE / (64 * KiB), > 1, 0x89, 0x18, 0x0000, 0x0, 1)) { > error_report("Error registering flash memory"); > /* XXX: return an error instead? */ > exit(1); > } > > - if (!blk) { > + if (!dinfo) { > /*error_report("No flash image given with the 'pflash' parameter= ," > " using default u-boot image");*/ > - base =3D UBOOT_LOAD_BASE | ((hwaddr)FLASH_BASE_H << 32); > - rom_add_file_fixed(UBOOT_FILENAME, base, -1); > + rom_add_file_fixed(UBOOT_FILENAME, > + UBOOT_LOAD_BASE | ((hwaddr)FLASH_BASE_H << 32= ), > + -1); > } > > return 0; -- Alex Benn=C3=A9e