diff options
author | Manuel Lauss <mano@roarinelk.homelinux.net> | 2008-12-21 09:26:24 +0100 |
---|---|---|
committer | Ralf Baechle <ralf@linux-mips.org> | 2009-01-11 09:57:27 +0000 |
commit | 2699cdfb765c3b7d77d28ea3bc7d84e486697177 (patch) | |
tree | 690eb6e847c7acfc0a5693a385907da480f33fd8 /arch/mips | |
parent | 0c694de12b54fa96b9555e07603f567906ce21c8 (diff) | |
download | op-kernel-dev-2699cdfb765c3b7d77d28ea3bc7d84e486697177.zip op-kernel-dev-2699cdfb765c3b7d77d28ea3bc7d84e486697177.tar.gz |
MIPS: Alchemy: move calc_clock function.
Now that nothing in time.c depends on calc_clock, it can
be moved to clocks.c where it belongs.
While at it, give it a better non-generic name and call it
as soon as possible in plat_mem_init.
Signed-off-by: Manuel Lauss <mano@roarinelk.homelinux.net>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips')
-rw-r--r-- | arch/mips/alchemy/common/clocks.c | 54 | ||||
-rw-r--r-- | arch/mips/alchemy/common/setup.c | 9 | ||||
-rw-r--r-- | arch/mips/alchemy/common/time.c | 54 | ||||
-rw-r--r-- | arch/mips/include/asm/mach-au1x00/au1000.h | 1 |
4 files changed, 64 insertions, 54 deletions
diff --git a/arch/mips/alchemy/common/clocks.c b/arch/mips/alchemy/common/clocks.c index a8170fd..d899185 100644 --- a/arch/mips/alchemy/common/clocks.c +++ b/arch/mips/alchemy/common/clocks.c @@ -27,11 +27,21 @@ */ #include <linux/module.h> +#include <linux/spinlock.h> +#include <asm/time.h> #include <asm/mach-au1x00/au1000.h> +/* + * I haven't found anyone that doesn't use a 12 MHz source clock, + * but just in case..... + */ +#define AU1000_SRC_CLK 12000000 + static unsigned int au1x00_clock; /* Hz */ static unsigned long uart_baud_base; +static DEFINE_SPINLOCK(time_lock); + /* * Set the au1000_clock */ @@ -60,3 +70,47 @@ void set_au1x00_uart_baud_base(unsigned long new_baud_base) { uart_baud_base = new_baud_base; } + +/* + * We read the real processor speed from the PLL. This is important + * because it is more accurate than computing it from the 32 KHz + * counter, if it exists. If we don't have an accurate processor + * speed, all of the peripherals that derive their clocks based on + * this advertised speed will introduce error and sometimes not work + * properly. This function is futher convoluted to still allow configurations + * to do that in case they have really, really old silicon with a + * write-only PLL register. -- Dan + */ +unsigned long au1xxx_calc_clock(void) +{ + unsigned long cpu_speed; + unsigned long flags; + + spin_lock_irqsave(&time_lock, flags); + + /* + * On early Au1000, sys_cpupll was write-only. Since these + * silicon versions of Au1000 are not sold by AMD, we don't bend + * over backwards trying to determine the frequency. + */ + if (au1xxx_cpu_has_pll_wo()) +#ifdef CONFIG_SOC_AU1000_FREQUENCY + cpu_speed = CONFIG_SOC_AU1000_FREQUENCY; +#else + cpu_speed = 396000000; +#endif + else + cpu_speed = (au_readl(SYS_CPUPLL) & 0x0000003f) * AU1000_SRC_CLK; + + /* On Alchemy CPU:counter ratio is 1:1 */ + mips_hpt_frequency = cpu_speed; + /* Equation: Baudrate = CPU / (SD * 2 * CLKDIV * 16) */ + set_au1x00_uart_baud_base(cpu_speed / (2 * ((int)(au_readl(SYS_POWERCTRL) + & 0x03) + 2) * 16)); + + spin_unlock_irqrestore(&time_lock, flags); + + set_au1x00_speed(cpu_speed); + + return cpu_speed; +} diff --git a/arch/mips/alchemy/common/setup.c b/arch/mips/alchemy/common/setup.c index 8ad453a..3f036b3 100644 --- a/arch/mips/alchemy/common/setup.c +++ b/arch/mips/alchemy/common/setup.c @@ -44,6 +44,15 @@ extern void set_cpuspec(void); void __init plat_mem_setup(void) { + unsigned long est_freq; + + /* determine core clock */ + est_freq = au1xxx_calc_clock(); + est_freq += 5000; /* round */ + est_freq -= est_freq % 10000; + printk(KERN_INFO "(PRId %08x) @ %lu.%02lu MHz\n", read_c0_prid(), + est_freq / 1000000, ((est_freq % 1000000) * 100) / 1000000); + _machine_restart = au1000_restart; _machine_halt = au1000_halt; pm_power_off = au1000_power_off; diff --git a/arch/mips/alchemy/common/time.c b/arch/mips/alchemy/common/time.c index 57f0aec..3288014 100644 --- a/arch/mips/alchemy/common/time.c +++ b/arch/mips/alchemy/common/time.c @@ -44,53 +44,6 @@ extern int allow_au1k_wait; /* default off for CP0 Counter */ -static DEFINE_SPINLOCK(time_lock); - -/* - * I haven't found anyone that doesn't use a 12 MHz source clock, - * but just in case..... - */ -#define AU1000_SRC_CLK 12000000 - -/* - * We read the real processor speed from the PLL. This is important - * because it is more accurate than computing it from the 32 KHz - * counter, if it exists. If we don't have an accurate processor - * speed, all of the peripherals that derive their clocks based on - * this advertised speed will introduce error and sometimes not work - * properly. This function is futher convoluted to still allow configurations - * to do that in case they have really, really old silicon with a - * write-only PLL register. -- Dan - */ -unsigned long calc_clock(void) -{ - unsigned long cpu_speed; - unsigned long flags; - - spin_lock_irqsave(&time_lock, flags); - - /* - * On early Au1000, sys_cpupll was write-only. Since these - * silicon versions of Au1000 are not sold by AMD, we don't bend - * over backwards trying to determine the frequency. - */ - if (au1xxx_cpu_has_pll_wo()) -#ifdef CONFIG_SOC_AU1000_FREQUENCY - cpu_speed = CONFIG_SOC_AU1000_FREQUENCY; -#else - cpu_speed = 396000000; -#endif - else - cpu_speed = (au_readl(SYS_CPUPLL) & 0x0000003f) * AU1000_SRC_CLK; - /* On Alchemy CPU:counter ratio is 1:1 */ - mips_hpt_frequency = cpu_speed; - /* Equation: Baudrate = CPU / (SD * 2 * CLKDIV * 16) */ - set_au1x00_uart_baud_base(cpu_speed / (2 * ((int)(au_readl(SYS_POWERCTRL) - & 0x03) + 2) * 16)); - spin_unlock_irqrestore(&time_lock, flags); - return cpu_speed; -} - static cycle_t au1x_counter1_read(void) { return au_readl(SYS_RTCREAD); @@ -150,13 +103,6 @@ void __init plat_time_init(void) { struct clock_event_device *cd = &au1x_rtcmatch2_clockdev; unsigned long t; - unsigned int est_freq = calc_clock(); - - est_freq += 5000; /* round */ - est_freq -= est_freq%10000; - printk(KERN_INFO "(PRId %08x) @ %u.%02u MHz\n", read_c0_prid(), - est_freq / 1000000, ((est_freq % 1000000) * 100) / 1000000); - set_au1x00_speed(est_freq); /* Check if firmware (YAMON, ...) has enabled 32kHz and clock * has been detected. If so install the rtcmatch2 clocksource, diff --git a/arch/mips/include/asm/mach-au1x00/au1000.h b/arch/mips/include/asm/mach-au1x00/au1000.h index 5db26e6..2b88c29 100644 --- a/arch/mips/include/asm/mach-au1x00/au1000.h +++ b/arch/mips/include/asm/mach-au1x00/au1000.h @@ -135,6 +135,7 @@ extern void set_au1x00_speed(unsigned int new_freq); extern unsigned int get_au1x00_speed(void); extern void set_au1x00_uart_baud_base(unsigned long new_baud_base); extern unsigned long get_au1x00_uart_baud_base(void); +extern unsigned long au1xxx_calc_clock(void); /* * Every board describes its IRQ mapping with this table. |