From: Lukasz Majewski Date: Tue, 03 Mar 2015 08:56:30 +0100 Subject: [U-Boot] [PATCH v2 1/6] x86: Support machines with >4GB of RAM In-Reply-To: <1425325255-6267-1-git-send-email-sjg@chromium.org> References: <1425325255-6267-1-git-send-email-sjg@chromium.org> Message-ID: <20150303085630.4ab6c5c1@amdc2363> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi Simon, > Some systems have more than 4GB of RAM. U-Boot can only place things > below 4GB so any memory above that should not be used. Ignore any > such memory so that the memory size will not exceed the maximum. > > This prevents gd->ram_size exceeding 4GB which causes problems for PCI > devices which use DMA. > > Signed-off-by: Simon Glass > Reviewed-by: Bin Meng > --- > > Changes in v2: None > > arch/x86/cpu/coreboot/sdram.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/cpu/coreboot/sdram.c > b/arch/x86/cpu/coreboot/sdram.c index e98a230..9c3ab81 100644 > --- a/arch/x86/cpu/coreboot/sdram.c > +++ b/arch/x86/cpu/coreboot/sdram.c > @@ -90,7 +90,8 @@ int dram_init(void) > struct memrange *memrange = &lib_sysinfo.memrange[i]; > unsigned long long end = memrange->base + > memrange->size; > - if (memrange->type == CB_MEM_RAM && end > ram_size) > + if (memrange->type == CB_MEM_RAM && end > ram_size && > + memrange->base < (1ULL << 32)) > ram_size = end; > } > gd->ram_size = ram_size; > @@ -108,7 +109,8 @@ void dram_init_banksize(void) > for (i = 0, j = 0; i < lib_sysinfo.n_memranges; i++) > { struct memrange *memrange = &lib_sysinfo.memrange[i]; > > - if (memrange->type == CB_MEM_RAM) { > + if (memrange->type == CB_MEM_RAM && > + memrange->base < (1ULL << 32)) { > gd->bd->bi_dram[j].start = > memrange->base; gd->bd->bi_dram[j].size = memrange->size; > j++; Reviewed-by: Lukasz Majewski -- Best regards, Lukasz Majewski Samsung R&D Institute Poland (SRPOL) | Linux Platform Group