From f31405cc4cc568baad28273c7f45b0563b57a17d Mon Sep 17 00:00:00 2001 From: Juergen Beisert Date: Sat, 5 Jul 2008 10:02:59 +0200 Subject: i.MX27 CPU: Add basic i.MX27 CPU support Add basic i.MX27 CPU support Signed-off-by: Juergen Beisert --- arch/arm/mach-mx2/cpu_imx27.c | 63 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 63 insertions(+) create mode 100644 arch/arm/mach-mx2/cpu_imx27.c (limited to 'arch/arm/mach-mx2/cpu_imx27.c') diff --git a/arch/arm/mach-mx2/cpu_imx27.c b/arch/arm/mach-mx2/cpu_imx27.c new file mode 100644 index 00000000000..d6b5c2e3377 --- /dev/null +++ b/arch/arm/mach-mx2/cpu_imx27.c @@ -0,0 +1,63 @@ +/* + * Copyright 2007 Freescale Semiconductor, Inc. All Rights Reserved. + * Copyright 2008 Juergen Beisert, kernel@pengutronix.de + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, + * MA 02110-1301, USA. + */ + +/* + * i.MX27 specific CPU detection code + */ + +#include +#include + +#include + +#include "crm_regs.h" + +static int cpu_silicon_rev = -1; +static int cpu_partnumber; + +static void query_silicon_parameter(void) +{ + u32 val; + /* + * now we have access to the IO registers. As we need + * the silicon revision very early we read it here to + * avoid any further hooks + */ + val = __raw_readl(IO_ADDRESS(SYSCTRL_BASE_ADDR) + SYS_CHIP_ID); + + cpu_silicon_rev = (int)(val >> 28); + cpu_partnumber = (int)((val >> 12) & 0xFFFF); +} + +/* + * Returns: + * the silicon revision of the cpu + * -EINVAL - not a mx27 + */ +int mx27_revision(void) +{ + if (cpu_silicon_rev == -1) + query_silicon_parameter(); + + if (cpu_partnumber != 0x8821) + return -EINVAL; + + return cpu_silicon_rev; +} +EXPORT_SYMBOL(mx27_revision); -- cgit v1.2.3