From mboxrd@z Thu Jan 1 00:00:00 1970 From: kgene.kim@samsung.com (Kukjin Kim) Date: Mon, 02 Aug 2010 11:26:12 +0900 Subject: [PATCH v5 1/7] ARM: S5PV210: Allow to probe EVT revision number. In-Reply-To: <1280399145-22761-2-git-send-email-myungjoo.ham@samsung.com> References: <1280399145-22761-1-git-send-email-myungjoo.ham@samsung.com> <1280399145-22761-2-git-send-email-myungjoo.ham@samsung.com> Message-ID: <018001cb31ea$158c84f0$40a58ed0$%kim@samsung.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org MyungJoo Ham wrote: > > Early products of S5PV210, EVT0, had several errata that require > kernel to avoid using some parts/instructions of the CPU or to > add protection instructions. There are products with such early > production CPUs; thus, we want to distinguish them in kernel. > This patch is to distinguish such products. > > Include and call s5pv210_revision(). > > For example, > > if (s5pv210_revision(EVT0)) { > ... execute code targeted only to EVT0 ... > } else { > ... execute normal code ... > } > > Call set_s5pv210_revision(EVTx) when the EVT revision number can be > identified. We have EVT0, EVT1, and EVT1-Fused avaialble right now and > only EVT1-Fused has the unique revision number at chipid (PRO_ID > register). A function, get_s5pv210_revision_chipid(), returns EVT > revision number if the revision is identified by the chipid; otherwise, > the function returns EVT_UNKNOWN. When EVT cannot be identified with > chipid, it can be identified at board support file > (arch/arm/mach-s5pv210/mach-*.c), not at the cpu file > (arch/arm/mach-s5pv210/cpu.c). > > For Aquila machine. (mach-aquila.c) > > Part of Aquila machines have the early production CPUs that require > to address errata issues. Note that we don't do this for GONI machines > because they have never used early production CPUs with errata. Besides, > please note that there are other boards that use such early produces > other than Aquila. However, those boards/machines are not registered at > the /linux/arch/arm/tools/mach-types, yet; thus, we have omitted them > in this patch. > > For Goni machine. (mach-goni.c) > > It's either EVT1 or EVT1-Fused; thus, it can be identified by > get_s5pv210_revision_chipid() function. > > Signed-off-by: MyungJoo Ham > Signed-off-by: Kyungmin Park > -- > v5: > - rename revision check function. > - revise revision check functions so that it does not access > board-related information. > - chipid is used to identify EVT revision. > - added "s5pv210_revision_or_later()" function > --- > arch/arm/mach-s5pv210/cpu.c | 29 > +++++++++++++++++++++++++ > arch/arm/mach-s5pv210/include/mach/hardware.h | 19 +++++++++++++++- > arch/arm/mach-s5pv210/mach-aquila.c | 14 ++++++++++++ > arch/arm/mach-s5pv210/mach-goni.c | 8 +++++++ > 4 files changed, 69 insertions(+), 1 deletions(-) > > diff --git a/arch/arm/mach-s5pv210/cpu.c b/arch/arm/mach-s5pv210/cpu.c > index 94c632b..77bf37d 100644 > --- a/arch/arm/mach-s5pv210/cpu.c > +++ b/arch/arm/mach-s5pv210/cpu.c > @@ -24,9 +24,11 @@ > #include > #include > > +#include > #include > #include > #include > +#include > > #include > #include > @@ -128,6 +130,33 @@ static struct sys_device s5pv210_sysdev = { > .cls = &s5pv210_sysclass, > }; > > +static enum s5pv210_revision s5pv210_evt_number = EVT_UNKNOWN; > + > +bool s5pv210_revision(enum s5pv210_revision rev) > +{ > + return rev == s5pv210_evt_number; > +} > + > +bool s5pv210_revision_or_later(enum s5pv210_revision rev) > +{ > + return rev >= s5pv210_evt_number; > +} > + > +void set_s5pv210_revision(enum s5pv210_revision rev) > +{ > + s5pv210_evt_number = rev; > +} > + > +enum s5pv210_revision get_s5pv210_revision_chipid(void) > +{ > + unsigned int reg = __raw_readl(S5P_VA_CHIPID); > + > + if ((reg & 0xf0) == 0x20) > + return EVT1_FUSED; > + > + return EVT_UNKNOWN; > +} > + > static int __init s5pv210_core_init(void) > { > return sysdev_class_register(&s5pv210_sysclass); > diff --git a/arch/arm/mach-s5pv210/include/mach/hardware.h b/arch/arm/mach- > s5pv210/include/mach/hardware.h > index fada7a3..c1702d6 100644 > --- a/arch/arm/mach-s5pv210/include/mach/hardware.h > +++ b/arch/arm/mach-s5pv210/include/mach/hardware.h > @@ -13,6 +13,23 @@ > #ifndef __ASM_ARCH_HARDWARE_H > #define __ASM_ARCH_HARDWARE_H __FILE__ > > -/* currently nothing here, placeholder */ > +enum s5pv210_revision { EVT_UNKNOWN = 0, > + EVT0, > + EVT1, > + EVT1_FUSED }; Do we really need checking of 'EVT1_FUSED' in kernel? > + > +extern bool s5pv210_revision(enum s5pv210_revision); > +extern bool s5pv210_revision_or_later(enum s5pv210_revision); > +extern void set_s5pv210_revision(enum s5pv210_revision); > + > +/* > + * get_s5pv210_revision_chipid returns s5pv210_revision if the > + * EVT revision can be determined by the chipid(PRO_ID) register. > + * However, note that only EVT1-FUSED can be identified from it and > + * it cannot distinguish between EVT0 and EVT1. In such case, it > + * returns EVT_UNKNOWN. In such case use set_s5pv210_revision() to > + * set the revision number manually. > + */ > +extern enum s5pv210_revision get_s5pv210_revision_chipid(void); > > #endif /* __ASM_ARCH_HARDWARE_H */ > diff --git a/arch/arm/mach-s5pv210/mach-aquila.c b/arch/arm/mach-s5pv210/mach- > aquila.c > index 46d5c7e..25f45d1 100644 > --- a/arch/arm/mach-s5pv210/mach-aquila.c > +++ b/arch/arm/mach-s5pv210/mach-aquila.c > @@ -30,6 +30,7 @@ > #include > #include > #include > +#include > > #include > #include > @@ -536,6 +537,19 @@ static void __init aquila_map_io(void) > > static void __init aquila_machine_init(void) > { > + enum s5pv210_revision cpurev = get_s5pv210_revision_chipid(); > + > + /* CPU Revision (EVTx) */ > + if (cpurev == EVT_UNKNOWN) { If don't need 'EVT1_FUSED', maybe just need to check system_rev. > + cpurev = EVT1; > + if (system_rev & 0x0800) { > + if ((system_rev & 0xF) < 8) > + cpurev = EVT0; ... > + } else if (system_rev & 0x2000) > + cpurev = EVT0; ... > + } > + set_s5pv210_revision(cpurev); > + > /* PMIC */ > aquila_pmic_init(); > i2c_register_board_info(AP_I2C_GPIO_PMIC_BUS_4, > i2c_gpio_pmic_devs, > diff --git a/arch/arm/mach-s5pv210/mach-goni.c b/arch/arm/mach-s5pv210/mach- > goni.c > index 380d2ae..25a26ed 100644 > --- a/arch/arm/mach-s5pv210/mach-goni.c > +++ b/arch/arm/mach-s5pv210/mach-goni.c > @@ -32,6 +32,7 @@ > #include > #include > #include > +#include > > #include > #include > @@ -520,6 +521,13 @@ static void __init goni_map_io(void) > > static void __init goni_machine_init(void) > { > + enum s5pv210_revision cpurev = get_s5pv210_revision_chipid(); > + > + /* CPU Revision (EVTx) */ > + if (cpurev == EVT_UNKNOWN) > + cpurev = EVT1; is it available only EVT1 on GONI? > + set_s5pv210_revision(cpurev); > + > /* PMIC */ > goni_pmic_init(); > i2c_register_board_info(AP_I2C_GPIO_PMIC_BUS_4, > i2c_gpio_pmic_devs, > -- Thanks. Best regards, Kgene. -- Kukjin Kim , Senior Engineer, SW Solution Development Team, Samsung Electronics Co., Ltd.