* [PATCH] Add cpufreq driver for Momentum Maple boards
@ 2011-05-21 10:28 Dmitry Eremin-Solenikov
2011-05-30 11:57 ` Dmitry Eremin-Solenikov
2011-06-17 4:14 ` Benjamin Herrenschmidt
0 siblings, 2 replies; 11+ messages in thread
From: Dmitry Eremin-Solenikov @ 2011-05-21 10:28 UTC (permalink / raw)
To: cpufreq; +Cc: Dave Jones, Paul Mackerras, linuxppc-dev
Add simple cpufreq driver for Maple-based boards (ppc970fx evaluation
kit and others). Driver is based on a cpufreq driver for 64-bit powermac
boxes with all pmac-dependant features removed and simple cleanup
applied.
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
---
arch/powerpc/kernel/misc_64.S | 4 +-
arch/powerpc/platforms/Kconfig | 8 +
arch/powerpc/platforms/maple/Makefile | 1 +
arch/powerpc/platforms/maple/cpufreq.c | 317 ++++++++++++++++++++++++++++++++
4 files changed, 328 insertions(+), 2 deletions(-)
create mode 100644 arch/powerpc/platforms/maple/cpufreq.c
diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S
index 206a321..c442aae 100644
--- a/arch/powerpc/kernel/misc_64.S
+++ b/arch/powerpc/kernel/misc_64.S
@@ -339,7 +339,7 @@ _GLOBAL(real_205_writeb)
#endif /* CONFIG_PPC_PASEMI */
-#ifdef CONFIG_CPU_FREQ_PMAC64
+#if defined(CONFIG_CPU_FREQ_PMAC64) || defined(CONFIG_CPU_FREQ_MAPLE)
/*
* SCOM access functions for 970 (FX only for now)
*
@@ -408,7 +408,7 @@ _GLOBAL(scom970_write)
/* restore interrupts */
mtmsrd r5,1
blr
-#endif /* CONFIG_CPU_FREQ_PMAC64 */
+#endif /* CONFIG_CPU_FREQ_PMAC64 || CONFIG_CPU_FREQ_MAPLE */
/*
diff --git a/arch/powerpc/platforms/Kconfig b/arch/powerpc/platforms/Kconfig
index f7b0772..4c5eb5b 100644
--- a/arch/powerpc/platforms/Kconfig
+++ b/arch/powerpc/platforms/Kconfig
@@ -187,6 +187,14 @@ config PPC_PASEMI_CPUFREQ
This adds the support for frequency switching on PA Semi
PWRficient processors.
+config CPU_FREQ_MAPLE
+ bool "Support for Maple 970FX Evaluation Board"
+ depends on PPC_MAPLE
+ select CPU_FREQ_TABLE
+ help
+ This adds support for frequency switching on Maple 970FX
+ Evaluation Board and compatible boards (IBM JS2x blades).
+
endmenu
config PPC601_SYNC_FIX
diff --git a/arch/powerpc/platforms/maple/Makefile b/arch/powerpc/platforms/maple/Makefile
index 1be1a99..0b3e3e3 100644
--- a/arch/powerpc/platforms/maple/Makefile
+++ b/arch/powerpc/platforms/maple/Makefile
@@ -1 +1,2 @@
obj-y += setup.o pci.o time.o
+obj-$(CONFIG_CPU_FREQ_MAPLE) += cpufreq.o
diff --git a/arch/powerpc/platforms/maple/cpufreq.c b/arch/powerpc/platforms/maple/cpufreq.c
new file mode 100644
index 0000000..854adfa
--- /dev/null
+++ b/arch/powerpc/platforms/maple/cpufreq.c
@@ -0,0 +1,317 @@
+/*
+ * Copyright (C) 2011 Dmitry Eremin-Solenikov
+ * Copyright (C) 2002 - 2005 Benjamin Herrenschmidt <benh@kernel.crashing.org>
+ * and Markus Demleitner <msdemlei@cl.uni-heidelberg.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This driver adds basic cpufreq support for SMU & 970FX based G5 Macs,
+ * that is iMac G5 and latest single CPU desktop.
+ */
+
+#undef DEBUG
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/sched.h>
+#include <linux/cpufreq.h>
+#include <linux/init.h>
+#include <linux/completion.h>
+#include <linux/mutex.h>
+#include <asm/prom.h>
+#include <asm/machdep.h>
+#include <asm/irq.h>
+#include <asm/sections.h>
+#include <asm/cputable.h>
+#include <asm/time.h>
+
+#define DBG(fmt...) pr_debug(fmt)
+
+/* see 970FX user manual */
+
+#define SCOM_PCR 0x0aa001 /* PCR scom addr */
+
+#define PCR_HILO_SELECT 0x80000000U /* 1 = PCR, 0 = PCRH */
+#define PCR_SPEED_FULL 0x00000000U /* 1:1 speed value */
+#define PCR_SPEED_HALF 0x00020000U /* 1:2 speed value */
+#define PCR_SPEED_QUARTER 0x00040000U /* 1:4 speed value */
+#define PCR_SPEED_MASK 0x000e0000U /* speed mask */
+#define PCR_SPEED_SHIFT 17
+#define PCR_FREQ_REQ_VALID 0x00010000U /* freq request valid */
+#define PCR_VOLT_REQ_VALID 0x00008000U /* volt request valid */
+#define PCR_TARGET_TIME_MASK 0x00006000U /* target time */
+#define PCR_STATLAT_MASK 0x00001f00U /* STATLAT value */
+#define PCR_SNOOPLAT_MASK 0x000000f0U /* SNOOPLAT value */
+#define PCR_SNOOPACC_MASK 0x0000000fU /* SNOOPACC value */
+
+#define SCOM_PSR 0x408001 /* PSR scom addr */
+/* warning: PSR is a 64 bits register */
+#define PSR_CMD_RECEIVED 0x2000000000000000U /* command received */
+#define PSR_CMD_COMPLETED 0x1000000000000000U /* command completed */
+#define PSR_CUR_SPEED_MASK 0x0300000000000000U /* current speed */
+#define PSR_CUR_SPEED_SHIFT (56)
+
+/*
+ * The G5 only supports two frequencies (Quarter speed is not supported)
+ */
+#define CPUFREQ_HIGH 0
+#define CPUFREQ_LOW 1
+
+static struct cpufreq_frequency_table g5_cpu_freqs[] = {
+ {CPUFREQ_HIGH, 0},
+ {CPUFREQ_LOW, 0},
+ {0, CPUFREQ_TABLE_END},
+};
+
+static struct freq_attr* g5_cpu_freqs_attr[] = {
+ &cpufreq_freq_attr_scaling_available_freqs,
+ NULL,
+};
+
+/* Power mode data is an array of the 32 bits PCR values to use for
+ * the various frequencies, retrieved from the device-tree
+ */
+static int g5_pmode_cur;
+
+static DEFINE_MUTEX(g5_switch_mutex);
+
+static const u32 *g5_pmode_data;
+static int g5_pmode_max;
+
+/*
+ * Fake voltage switching for platforms with missing support
+ */
+
+static void g5_dummy_switch_volt(int speed_mode)
+{
+}
+
+/*
+ * SCOM based frequency switching for 970FX rev3
+ */
+static int g5_scom_switch_freq(int speed_mode)
+{
+ unsigned long flags;
+ int to;
+
+ /* If frequency is going up, first ramp up the voltage */
+ if (speed_mode < g5_pmode_cur)
+ g5_dummy_switch_volt(speed_mode);
+
+ local_irq_save(flags);
+
+ /* Clear PCR high */
+ scom970_write(SCOM_PCR, 0);
+ /* Clear PCR low */
+ scom970_write(SCOM_PCR, PCR_HILO_SELECT | 0);
+ /* Set PCR low */
+ scom970_write(SCOM_PCR, PCR_HILO_SELECT |
+ g5_pmode_data[speed_mode]);
+
+ /* Wait for completion */
+ for (to = 0; to < 10; to++) {
+ unsigned long psr = scom970_read(SCOM_PSR);
+
+ if ((psr & PSR_CMD_RECEIVED) == 0 &&
+ (((psr >> PSR_CUR_SPEED_SHIFT) ^
+ (g5_pmode_data[speed_mode] >> PCR_SPEED_SHIFT)) & 0x3)
+ == 0)
+ break;
+ if (psr & PSR_CMD_COMPLETED)
+ break;
+ udelay(100);
+ }
+
+ local_irq_restore(flags);
+
+ /* If frequency is going down, last ramp the voltage */
+ if (speed_mode > g5_pmode_cur)
+ g5_dummy_switch_volt(speed_mode);
+
+ g5_pmode_cur = speed_mode;
+ ppc_proc_freq = g5_cpu_freqs[speed_mode].frequency * 1000ul;
+
+ return 0;
+}
+
+static int g5_scom_query_freq(void)
+{
+ unsigned long psr = scom970_read(SCOM_PSR);
+ int i;
+
+ for (i = 0; i <= g5_pmode_max; i++)
+ if ((((psr >> PSR_CUR_SPEED_SHIFT) ^
+ (g5_pmode_data[i] >> PCR_SPEED_SHIFT)) & 0x3) == 0)
+ break;
+ return i;
+}
+
+/*
+ * Common interface to the cpufreq core
+ */
+
+static int g5_cpufreq_verify(struct cpufreq_policy *policy)
+{
+ return cpufreq_frequency_table_verify(policy, g5_cpu_freqs);
+}
+
+static int g5_cpufreq_target(struct cpufreq_policy *policy,
+ unsigned int target_freq, unsigned int relation)
+{
+ unsigned int newstate = 0;
+ struct cpufreq_freqs freqs;
+ int rc;
+
+ if (cpufreq_frequency_table_target(policy, g5_cpu_freqs,
+ target_freq, relation, &newstate))
+ return -EINVAL;
+
+ if (g5_pmode_cur == newstate)
+ return 0;
+
+ mutex_lock(&g5_switch_mutex);
+
+ freqs.old = g5_cpu_freqs[g5_pmode_cur].frequency;
+ freqs.new = g5_cpu_freqs[newstate].frequency;
+ freqs.cpu = 0;
+
+ cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
+ rc = g5_scom_switch_freq(newstate);
+ cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
+
+ mutex_unlock(&g5_switch_mutex);
+
+ return rc;
+}
+
+static unsigned int g5_cpufreq_get_speed(unsigned int cpu)
+{
+ return g5_cpu_freqs[g5_pmode_cur].frequency;
+}
+
+static int g5_cpufreq_cpu_init(struct cpufreq_policy *policy)
+{
+ policy->cpuinfo.transition_latency = 12000;
+ policy->cur = g5_cpu_freqs[g5_scom_query_freq()].frequency;
+ /* secondary CPUs are tied to the primary one by the
+ * cpufreq core if in the secondary policy we tell it that
+ * it actually must be one policy together with all others. */
+ cpumask_copy(policy->cpus, cpu_online_mask);
+ cpufreq_frequency_table_get_attr(g5_cpu_freqs, policy->cpu);
+
+ return cpufreq_frequency_table_cpuinfo(policy,
+ g5_cpu_freqs);
+}
+
+
+static struct cpufreq_driver g5_cpufreq_driver = {
+ .name = "maple",
+ .owner = THIS_MODULE,
+ .flags = CPUFREQ_CONST_LOOPS,
+ .init = g5_cpufreq_cpu_init,
+ .verify = g5_cpufreq_verify,
+ .target = g5_cpufreq_target,
+ .get = g5_cpufreq_get_speed,
+ .attr = g5_cpu_freqs_attr,
+};
+
+static int __init g5_cpufreq_init(void)
+{
+ struct device_node *cpus;
+ struct device_node *cpunode;
+ unsigned int psize;
+ unsigned long max_freq;
+ const u32 *valp;
+ u32 pvr_hi;
+ int rc = -ENODEV;
+
+ cpus = of_find_node_by_path("/cpus");
+ if (cpus == NULL) {
+ DBG("No /cpus node !\n");
+ return -ENODEV;
+ }
+
+ /* Get first CPU node */
+ for (cpunode = NULL;
+ (cpunode = of_get_next_child(cpus, cpunode)) != NULL;) {
+ const u32 *reg = of_get_property(cpunode, "reg", NULL);
+ if (reg == NULL || (*reg) != 0)
+ continue;
+ if (!strcmp(cpunode->type, "cpu"))
+ break;
+ }
+ if (cpunode == NULL) {
+ printk(KERN_ERR "cpufreq: Can't find any CPU 0 node\n");
+ goto bail_cpus;
+ }
+
+ /* Check 970FX for now */
+ /* we actually don't care on which CPU to access PVR */
+ pvr_hi = PVR_VER(mfspr(SPRN_PVR));
+ if (pvr_hi != 0x3c && pvr_hi != 0x44) {
+ printk(KERN_ERR "cpufreq: Unsupported CPU version (%x)\n", pvr_hi);
+ goto bail_noprops;
+ }
+
+ /* Look for the powertune data in the device-tree */
+ g5_pmode_data = of_get_property(cpunode, "power-mode-data",&psize);
+ if (!g5_pmode_data) {
+ DBG("No power-mode-data !\n");
+ goto bail_noprops;
+ }
+ g5_pmode_max = psize / sizeof(u32) - 1;
+
+ /*
+ * From what I see, clock-frequency is always the maximal frequency.
+ * The current driver can not slew sysclk yet, so we really only deal
+ * with powertune steps for now. We also only implement full freq and
+ * half freq in this version. So far, I haven't yet seen a machine
+ * supporting anything else.
+ */
+ valp = of_get_property(cpunode, "clock-frequency", NULL);
+ if (!valp)
+ return -ENODEV;
+ max_freq = (*valp)/1000;
+ g5_cpu_freqs[0].frequency = max_freq;
+ g5_cpu_freqs[1].frequency = max_freq/2;
+
+ /* Force apply current frequency to make sure everything is in
+ * sync (voltage is right for example). Firmware may leave us with
+ * a strange setting ...
+ */
+ g5_dummy_switch_volt(CPUFREQ_HIGH);
+ msleep(10);
+ g5_pmode_cur = -1;
+ g5_scom_switch_freq(g5_scom_query_freq());
+
+ printk(KERN_INFO "Registering G5 CPU frequency driver\n");
+ printk(KERN_INFO "Frequency method: SCOM, Voltage method: none\n");
+ printk(KERN_INFO "Low: %d Mhz, High: %d Mhz, Cur: %d MHz\n",
+ g5_cpu_freqs[1].frequency/1000,
+ g5_cpu_freqs[0].frequency/1000,
+ g5_cpu_freqs[g5_pmode_cur].frequency/1000);
+
+ rc = cpufreq_register_driver(&g5_cpufreq_driver);
+
+ of_node_put(cpunode);
+ of_node_put(cpus);
+
+ return rc;
+
+bail_noprops:
+ of_node_put(cpunode);
+bail_cpus:
+ of_node_put(cpus);
+
+ return rc;
+}
+
+module_init(g5_cpufreq_init);
+
+
+MODULE_LICENSE("GPL");
--
1.7.4.4
^ permalink raw reply related [flat|nested] 11+ messages in thread* Re: [PATCH] Add cpufreq driver for Momentum Maple boards
2011-05-21 10:28 [PATCH] Add cpufreq driver for Momentum Maple boards Dmitry Eremin-Solenikov
@ 2011-05-30 11:57 ` Dmitry Eremin-Solenikov
2011-06-04 9:00 ` Dmitry Eremin-Solenikov
2011-06-17 4:14 ` Benjamin Herrenschmidt
1 sibling, 1 reply; 11+ messages in thread
From: Dmitry Eremin-Solenikov @ 2011-05-30 11:57 UTC (permalink / raw)
To: cpufreq; +Cc: Dave Jones, Paul Mackerras, linuxppc-dev
Hello,
On 5/21/11, Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> wrote:
> Add simple cpufreq driver for Maple-based boards (ppc970fx evaluation
> kit and others). Driver is based on a cpufreq driver for 64-bit powermac
> boxes with all pmac-dependant features removed and simple cleanup
> applied.
>
> Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
> ---
> arch/powerpc/kernel/misc_64.S | 4 +-
> arch/powerpc/platforms/Kconfig | 8 +
> arch/powerpc/platforms/maple/Makefile | 1 +
> arch/powerpc/platforms/maple/cpufreq.c | 317
> ++++++++++++++++++++++++++++++++
> 4 files changed, 328 insertions(+), 2 deletions(-)
> create mode 100644 arch/powerpc/platforms/maple/cpufreq.c
What about this patch?
--
With best wishes
Dmitry
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH] Add cpufreq driver for Momentum Maple boards
2011-05-30 11:57 ` Dmitry Eremin-Solenikov
@ 2011-06-04 9:00 ` Dmitry Eremin-Solenikov
2011-06-04 10:29 ` Benjamin Herrenschmidt
0 siblings, 1 reply; 11+ messages in thread
From: Dmitry Eremin-Solenikov @ 2011-06-04 9:00 UTC (permalink / raw)
To: cpufreq; +Cc: Dave Jones, Paul Mackerras, linuxppc-dev
On 5/30/11, Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> wrote:
> Hello,
>
> On 5/21/11, Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> wrote:
>> Add simple cpufreq driver for Maple-based boards (ppc970fx evaluation
>> kit and others). Driver is based on a cpufreq driver for 64-bit powermac
>> boxes with all pmac-dependant features removed and simple cleanup
>> applied.
>>
>> Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
>> ---
>> arch/powerpc/kernel/misc_64.S | 4 +-
>> arch/powerpc/platforms/Kconfig | 8 +
>> arch/powerpc/platforms/maple/Makefile | 1 +
>> arch/powerpc/platforms/maple/cpufreq.c | 317
>> ++++++++++++++++++++++++++++++++
>> 4 files changed, 328 insertions(+), 2 deletions(-)
>> create mode 100644 arch/powerpc/platforms/maple/cpufreq.c
>
> What about this patch?
Pinging again. Any problems/comments/objections to this patch?
--
With best wishes
Dmitry
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH] Add cpufreq driver for Momentum Maple boards
2011-06-04 9:00 ` Dmitry Eremin-Solenikov
@ 2011-06-04 10:29 ` Benjamin Herrenschmidt
2011-06-04 10:39 ` Dmitry Eremin-Solenikov
0 siblings, 1 reply; 11+ messages in thread
From: Benjamin Herrenschmidt @ 2011-06-04 10:29 UTC (permalink / raw)
To: Dmitry Eremin-Solenikov; +Cc: Dave Jones, Paul Mackerras, linuxppc-dev, cpufreq
On Sat, 2011-06-04 at 13:00 +0400, Dmitry Eremin-Solenikov wrote:
> On 5/30/11, Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> wrote:
> > Hello,
> >
> > On 5/21/11, Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> wrote:
> >> Add simple cpufreq driver for Maple-based boards (ppc970fx evaluation
> >> kit and others). Driver is based on a cpufreq driver for 64-bit powermac
> >> boxes with all pmac-dependant features removed and simple cleanup
> >> applied.
> >>
> >> Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
> >> ---
> >> arch/powerpc/kernel/misc_64.S | 4 +-
> >> arch/powerpc/platforms/Kconfig | 8 +
> >> arch/powerpc/platforms/maple/Makefile | 1 +
> >> arch/powerpc/platforms/maple/cpufreq.c | 317
> >> ++++++++++++++++++++++++++++++++
> >> 4 files changed, 328 insertions(+), 2 deletions(-)
> >> create mode 100644 arch/powerpc/platforms/maple/cpufreq.c
> >
> > What about this patch?
>
> Pinging again. Any problems/comments/objections to this patch?
Well, obviously nobody had time to review it yet....
Cheers,
Ben.
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH] Add cpufreq driver for Momentum Maple boards
2011-06-04 10:29 ` Benjamin Herrenschmidt
@ 2011-06-04 10:39 ` Dmitry Eremin-Solenikov
0 siblings, 0 replies; 11+ messages in thread
From: Dmitry Eremin-Solenikov @ 2011-06-04 10:39 UTC (permalink / raw)
To: Benjamin Herrenschmidt; +Cc: Dave Jones, Paul Mackerras, linuxppc-dev, cpufreq
On 6/4/11, Benjamin Herrenschmidt <benh@kernel.crashing.org> wrote:
> On Sat, 2011-06-04 at 13:00 +0400, Dmitry Eremin-Solenikov wrote:
>> On 5/30/11, Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> wrote:
>> > Hello,
>> >
>> > On 5/21/11, Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> wrote:
>> >> Add simple cpufreq driver for Maple-based boards (ppc970fx evaluation
>> >> kit and others). Driver is based on a cpufreq driver for 64-bit
>> >> powermac
>> >> boxes with all pmac-dependant features removed and simple cleanup
>> >> applied.
>> >>
>> >> Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
>> >> ---
>> >> arch/powerpc/kernel/misc_64.S | 4 +-
>> >> arch/powerpc/platforms/Kconfig | 8 +
>> >> arch/powerpc/platforms/maple/Makefile | 1 +
>> >> arch/powerpc/platforms/maple/cpufreq.c | 317
>> >> ++++++++++++++++++++++++++++++++
>> >> 4 files changed, 328 insertions(+), 2 deletions(-)
>> >> create mode 100644 arch/powerpc/platforms/maple/cpufreq.c
>> >
>> > What about this patch?
>>
>> Pinging again. Any problems/comments/objections to this patch?
>
> Well, obviously nobody had time to review it yet....
I'm just a bit impatient. It has been already two weeks...
--
With best wishes
Dmitry
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH] Add cpufreq driver for Momentum Maple boards
2011-05-21 10:28 [PATCH] Add cpufreq driver for Momentum Maple boards Dmitry Eremin-Solenikov
2011-05-30 11:57 ` Dmitry Eremin-Solenikov
@ 2011-06-17 4:14 ` Benjamin Herrenschmidt
2011-06-17 8:49 ` Dmitry Eremin-Solenikov
1 sibling, 1 reply; 11+ messages in thread
From: Benjamin Herrenschmidt @ 2011-06-17 4:14 UTC (permalink / raw)
To: Dmitry Eremin-Solenikov; +Cc: Dave Jones, Paul Mackerras, linuxppc-dev, cpufreq
On Sat, 2011-05-21 at 14:28 +0400, Dmitry Eremin-Solenikov wrote:
> Add simple cpufreq driver for Maple-based boards (ppc970fx evaluation
> kit and others). Driver is based on a cpufreq driver for 64-bit powermac
> boxes with all pmac-dependant features removed and simple cleanup
> applied.
No special comment other than please replace all the g5_* with maple_
for consistency.
Cheers,
Ben.
> Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
> ---
> arch/powerpc/kernel/misc_64.S | 4 +-
> arch/powerpc/platforms/Kconfig | 8 +
> arch/powerpc/platforms/maple/Makefile | 1 +
> arch/powerpc/platforms/maple/cpufreq.c | 317 ++++++++++++++++++++++++++++++++
> 4 files changed, 328 insertions(+), 2 deletions(-)
> create mode 100644 arch/powerpc/platforms/maple/cpufreq.c
>
> diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S
> index 206a321..c442aae 100644
> --- a/arch/powerpc/kernel/misc_64.S
> +++ b/arch/powerpc/kernel/misc_64.S
> @@ -339,7 +339,7 @@ _GLOBAL(real_205_writeb)
> #endif /* CONFIG_PPC_PASEMI */
>
>
> -#ifdef CONFIG_CPU_FREQ_PMAC64
> +#if defined(CONFIG_CPU_FREQ_PMAC64) || defined(CONFIG_CPU_FREQ_MAPLE)
> /*
> * SCOM access functions for 970 (FX only for now)
> *
> @@ -408,7 +408,7 @@ _GLOBAL(scom970_write)
> /* restore interrupts */
> mtmsrd r5,1
> blr
> -#endif /* CONFIG_CPU_FREQ_PMAC64 */
> +#endif /* CONFIG_CPU_FREQ_PMAC64 || CONFIG_CPU_FREQ_MAPLE */
>
>
> /*
> diff --git a/arch/powerpc/platforms/Kconfig b/arch/powerpc/platforms/Kconfig
> index f7b0772..4c5eb5b 100644
> --- a/arch/powerpc/platforms/Kconfig
> +++ b/arch/powerpc/platforms/Kconfig
> @@ -187,6 +187,14 @@ config PPC_PASEMI_CPUFREQ
> This adds the support for frequency switching on PA Semi
> PWRficient processors.
>
> +config CPU_FREQ_MAPLE
> + bool "Support for Maple 970FX Evaluation Board"
> + depends on PPC_MAPLE
> + select CPU_FREQ_TABLE
> + help
> + This adds support for frequency switching on Maple 970FX
> + Evaluation Board and compatible boards (IBM JS2x blades).
> +
> endmenu
>
> config PPC601_SYNC_FIX
> diff --git a/arch/powerpc/platforms/maple/Makefile b/arch/powerpc/platforms/maple/Makefile
> index 1be1a99..0b3e3e3 100644
> --- a/arch/powerpc/platforms/maple/Makefile
> +++ b/arch/powerpc/platforms/maple/Makefile
> @@ -1 +1,2 @@
> obj-y += setup.o pci.o time.o
> +obj-$(CONFIG_CPU_FREQ_MAPLE) += cpufreq.o
> diff --git a/arch/powerpc/platforms/maple/cpufreq.c b/arch/powerpc/platforms/maple/cpufreq.c
> new file mode 100644
> index 0000000..854adfa
> --- /dev/null
> +++ b/arch/powerpc/platforms/maple/cpufreq.c
> @@ -0,0 +1,317 @@
> +/*
> + * Copyright (C) 2011 Dmitry Eremin-Solenikov
> + * Copyright (C) 2002 - 2005 Benjamin Herrenschmidt <benh@kernel.crashing.org>
> + * and Markus Demleitner <msdemlei@cl.uni-heidelberg.de>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This driver adds basic cpufreq support for SMU & 970FX based G5 Macs,
> + * that is iMac G5 and latest single CPU desktop.
> + */
> +
> +#undef DEBUG
> +
> +#include <linux/module.h>
> +#include <linux/types.h>
> +#include <linux/errno.h>
> +#include <linux/kernel.h>
> +#include <linux/delay.h>
> +#include <linux/sched.h>
> +#include <linux/cpufreq.h>
> +#include <linux/init.h>
> +#include <linux/completion.h>
> +#include <linux/mutex.h>
> +#include <asm/prom.h>
> +#include <asm/machdep.h>
> +#include <asm/irq.h>
> +#include <asm/sections.h>
> +#include <asm/cputable.h>
> +#include <asm/time.h>
> +
> +#define DBG(fmt...) pr_debug(fmt)
> +
> +/* see 970FX user manual */
> +
> +#define SCOM_PCR 0x0aa001 /* PCR scom addr */
> +
> +#define PCR_HILO_SELECT 0x80000000U /* 1 = PCR, 0 = PCRH */
> +#define PCR_SPEED_FULL 0x00000000U /* 1:1 speed value */
> +#define PCR_SPEED_HALF 0x00020000U /* 1:2 speed value */
> +#define PCR_SPEED_QUARTER 0x00040000U /* 1:4 speed value */
> +#define PCR_SPEED_MASK 0x000e0000U /* speed mask */
> +#define PCR_SPEED_SHIFT 17
> +#define PCR_FREQ_REQ_VALID 0x00010000U /* freq request valid */
> +#define PCR_VOLT_REQ_VALID 0x00008000U /* volt request valid */
> +#define PCR_TARGET_TIME_MASK 0x00006000U /* target time */
> +#define PCR_STATLAT_MASK 0x00001f00U /* STATLAT value */
> +#define PCR_SNOOPLAT_MASK 0x000000f0U /* SNOOPLAT value */
> +#define PCR_SNOOPACC_MASK 0x0000000fU /* SNOOPACC value */
> +
> +#define SCOM_PSR 0x408001 /* PSR scom addr */
> +/* warning: PSR is a 64 bits register */
> +#define PSR_CMD_RECEIVED 0x2000000000000000U /* command received */
> +#define PSR_CMD_COMPLETED 0x1000000000000000U /* command completed */
> +#define PSR_CUR_SPEED_MASK 0x0300000000000000U /* current speed */
> +#define PSR_CUR_SPEED_SHIFT (56)
> +
> +/*
> + * The G5 only supports two frequencies (Quarter speed is not supported)
> + */
> +#define CPUFREQ_HIGH 0
> +#define CPUFREQ_LOW 1
> +
> +static struct cpufreq_frequency_table g5_cpu_freqs[] = {
> + {CPUFREQ_HIGH, 0},
> + {CPUFREQ_LOW, 0},
> + {0, CPUFREQ_TABLE_END},
> +};
> +
> +static struct freq_attr* g5_cpu_freqs_attr[] = {
> + &cpufreq_freq_attr_scaling_available_freqs,
> + NULL,
> +};
> +
> +/* Power mode data is an array of the 32 bits PCR values to use for
> + * the various frequencies, retrieved from the device-tree
> + */
> +static int g5_pmode_cur;
> +
> +static DEFINE_MUTEX(g5_switch_mutex);
> +
> +static const u32 *g5_pmode_data;
> +static int g5_pmode_max;
> +
> +/*
> + * Fake voltage switching for platforms with missing support
> + */
> +
> +static void g5_dummy_switch_volt(int speed_mode)
> +{
> +}
> +
> +/*
> + * SCOM based frequency switching for 970FX rev3
> + */
> +static int g5_scom_switch_freq(int speed_mode)
> +{
> + unsigned long flags;
> + int to;
> +
> + /* If frequency is going up, first ramp up the voltage */
> + if (speed_mode < g5_pmode_cur)
> + g5_dummy_switch_volt(speed_mode);
> +
> + local_irq_save(flags);
> +
> + /* Clear PCR high */
> + scom970_write(SCOM_PCR, 0);
> + /* Clear PCR low */
> + scom970_write(SCOM_PCR, PCR_HILO_SELECT | 0);
> + /* Set PCR low */
> + scom970_write(SCOM_PCR, PCR_HILO_SELECT |
> + g5_pmode_data[speed_mode]);
> +
> + /* Wait for completion */
> + for (to = 0; to < 10; to++) {
> + unsigned long psr = scom970_read(SCOM_PSR);
> +
> + if ((psr & PSR_CMD_RECEIVED) == 0 &&
> + (((psr >> PSR_CUR_SPEED_SHIFT) ^
> + (g5_pmode_data[speed_mode] >> PCR_SPEED_SHIFT)) & 0x3)
> + == 0)
> + break;
> + if (psr & PSR_CMD_COMPLETED)
> + break;
> + udelay(100);
> + }
> +
> + local_irq_restore(flags);
> +
> + /* If frequency is going down, last ramp the voltage */
> + if (speed_mode > g5_pmode_cur)
> + g5_dummy_switch_volt(speed_mode);
> +
> + g5_pmode_cur = speed_mode;
> + ppc_proc_freq = g5_cpu_freqs[speed_mode].frequency * 1000ul;
> +
> + return 0;
> +}
> +
> +static int g5_scom_query_freq(void)
> +{
> + unsigned long psr = scom970_read(SCOM_PSR);
> + int i;
> +
> + for (i = 0; i <= g5_pmode_max; i++)
> + if ((((psr >> PSR_CUR_SPEED_SHIFT) ^
> + (g5_pmode_data[i] >> PCR_SPEED_SHIFT)) & 0x3) == 0)
> + break;
> + return i;
> +}
> +
> +/*
> + * Common interface to the cpufreq core
> + */
> +
> +static int g5_cpufreq_verify(struct cpufreq_policy *policy)
> +{
> + return cpufreq_frequency_table_verify(policy, g5_cpu_freqs);
> +}
> +
> +static int g5_cpufreq_target(struct cpufreq_policy *policy,
> + unsigned int target_freq, unsigned int relation)
> +{
> + unsigned int newstate = 0;
> + struct cpufreq_freqs freqs;
> + int rc;
> +
> + if (cpufreq_frequency_table_target(policy, g5_cpu_freqs,
> + target_freq, relation, &newstate))
> + return -EINVAL;
> +
> + if (g5_pmode_cur == newstate)
> + return 0;
> +
> + mutex_lock(&g5_switch_mutex);
> +
> + freqs.old = g5_cpu_freqs[g5_pmode_cur].frequency;
> + freqs.new = g5_cpu_freqs[newstate].frequency;
> + freqs.cpu = 0;
> +
> + cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
> + rc = g5_scom_switch_freq(newstate);
> + cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
> +
> + mutex_unlock(&g5_switch_mutex);
> +
> + return rc;
> +}
> +
> +static unsigned int g5_cpufreq_get_speed(unsigned int cpu)
> +{
> + return g5_cpu_freqs[g5_pmode_cur].frequency;
> +}
> +
> +static int g5_cpufreq_cpu_init(struct cpufreq_policy *policy)
> +{
> + policy->cpuinfo.transition_latency = 12000;
> + policy->cur = g5_cpu_freqs[g5_scom_query_freq()].frequency;
> + /* secondary CPUs are tied to the primary one by the
> + * cpufreq core if in the secondary policy we tell it that
> + * it actually must be one policy together with all others. */
> + cpumask_copy(policy->cpus, cpu_online_mask);
> + cpufreq_frequency_table_get_attr(g5_cpu_freqs, policy->cpu);
> +
> + return cpufreq_frequency_table_cpuinfo(policy,
> + g5_cpu_freqs);
> +}
> +
> +
> +static struct cpufreq_driver g5_cpufreq_driver = {
> + .name = "maple",
> + .owner = THIS_MODULE,
> + .flags = CPUFREQ_CONST_LOOPS,
> + .init = g5_cpufreq_cpu_init,
> + .verify = g5_cpufreq_verify,
> + .target = g5_cpufreq_target,
> + .get = g5_cpufreq_get_speed,
> + .attr = g5_cpu_freqs_attr,
> +};
> +
> +static int __init g5_cpufreq_init(void)
> +{
> + struct device_node *cpus;
> + struct device_node *cpunode;
> + unsigned int psize;
> + unsigned long max_freq;
> + const u32 *valp;
> + u32 pvr_hi;
> + int rc = -ENODEV;
> +
> + cpus = of_find_node_by_path("/cpus");
> + if (cpus == NULL) {
> + DBG("No /cpus node !\n");
> + return -ENODEV;
> + }
> +
> + /* Get first CPU node */
> + for (cpunode = NULL;
> + (cpunode = of_get_next_child(cpus, cpunode)) != NULL;) {
> + const u32 *reg = of_get_property(cpunode, "reg", NULL);
> + if (reg == NULL || (*reg) != 0)
> + continue;
> + if (!strcmp(cpunode->type, "cpu"))
> + break;
> + }
> + if (cpunode == NULL) {
> + printk(KERN_ERR "cpufreq: Can't find any CPU 0 node\n");
> + goto bail_cpus;
> + }
> +
> + /* Check 970FX for now */
> + /* we actually don't care on which CPU to access PVR */
> + pvr_hi = PVR_VER(mfspr(SPRN_PVR));
> + if (pvr_hi != 0x3c && pvr_hi != 0x44) {
> + printk(KERN_ERR "cpufreq: Unsupported CPU version (%x)\n", pvr_hi);
> + goto bail_noprops;
> + }
> +
> + /* Look for the powertune data in the device-tree */
> + g5_pmode_data = of_get_property(cpunode, "power-mode-data",&psize);
> + if (!g5_pmode_data) {
> + DBG("No power-mode-data !\n");
> + goto bail_noprops;
> + }
> + g5_pmode_max = psize / sizeof(u32) - 1;
> +
> + /*
> + * From what I see, clock-frequency is always the maximal frequency.
> + * The current driver can not slew sysclk yet, so we really only deal
> + * with powertune steps for now. We also only implement full freq and
> + * half freq in this version. So far, I haven't yet seen a machine
> + * supporting anything else.
> + */
> + valp = of_get_property(cpunode, "clock-frequency", NULL);
> + if (!valp)
> + return -ENODEV;
> + max_freq = (*valp)/1000;
> + g5_cpu_freqs[0].frequency = max_freq;
> + g5_cpu_freqs[1].frequency = max_freq/2;
> +
> + /* Force apply current frequency to make sure everything is in
> + * sync (voltage is right for example). Firmware may leave us with
> + * a strange setting ...
> + */
> + g5_dummy_switch_volt(CPUFREQ_HIGH);
> + msleep(10);
> + g5_pmode_cur = -1;
> + g5_scom_switch_freq(g5_scom_query_freq());
> +
> + printk(KERN_INFO "Registering G5 CPU frequency driver\n");
> + printk(KERN_INFO "Frequency method: SCOM, Voltage method: none\n");
> + printk(KERN_INFO "Low: %d Mhz, High: %d Mhz, Cur: %d MHz\n",
> + g5_cpu_freqs[1].frequency/1000,
> + g5_cpu_freqs[0].frequency/1000,
> + g5_cpu_freqs[g5_pmode_cur].frequency/1000);
> +
> + rc = cpufreq_register_driver(&g5_cpufreq_driver);
> +
> + of_node_put(cpunode);
> + of_node_put(cpus);
> +
> + return rc;
> +
> +bail_noprops:
> + of_node_put(cpunode);
> +bail_cpus:
> + of_node_put(cpus);
> +
> + return rc;
> +}
> +
> +module_init(g5_cpufreq_init);
> +
> +
> +MODULE_LICENSE("GPL");
^ permalink raw reply [flat|nested] 11+ messages in thread* [PATCH] Add cpufreq driver for Momentum Maple boards
2011-06-17 4:14 ` Benjamin Herrenschmidt
@ 2011-06-17 8:49 ` Dmitry Eremin-Solenikov
2011-06-17 9:17 ` Arnd Bergmann
0 siblings, 1 reply; 11+ messages in thread
From: Dmitry Eremin-Solenikov @ 2011-06-17 8:49 UTC (permalink / raw)
To: linuxppc-dev; +Cc: davej, paulus, cpufreq
Add simple cpufreq driver for Maple-based boards (ppc970fx evaluation
kit and others). Driver is based on a cpufreq driver for 64-bit powermac
boxes with all pmac-dependant features removed and simple cleanup
applied.
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
---
arch/powerpc/kernel/misc_64.S | 4 +-
arch/powerpc/platforms/Kconfig | 8 +
arch/powerpc/platforms/maple/Makefile | 1 +
arch/powerpc/platforms/maple/cpufreq.c | 317 ++++++++++++++++++++++++++++++++
4 files changed, 328 insertions(+), 2 deletions(-)
create mode 100644 arch/powerpc/platforms/maple/cpufreq.c
diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S
index e89df59..616921e 100644
--- a/arch/powerpc/kernel/misc_64.S
+++ b/arch/powerpc/kernel/misc_64.S
@@ -339,7 +339,7 @@ _GLOBAL(real_205_writeb)
#endif /* CONFIG_PPC_PASEMI */
-#ifdef CONFIG_CPU_FREQ_PMAC64
+#if defined(CONFIG_CPU_FREQ_PMAC64) || defined(CONFIG_CPU_FREQ_MAPLE)
/*
* SCOM access functions for 970 (FX only for now)
*
@@ -408,7 +408,7 @@ _GLOBAL(scom970_write)
/* restore interrupts */
mtmsrd r5,1
blr
-#endif /* CONFIG_CPU_FREQ_PMAC64 */
+#endif /* CONFIG_CPU_FREQ_PMAC64 || CONFIG_CPU_FREQ_MAPLE */
/*
diff --git a/arch/powerpc/platforms/Kconfig b/arch/powerpc/platforms/Kconfig
index f970ca2..96ab3ab 100644
--- a/arch/powerpc/platforms/Kconfig
+++ b/arch/powerpc/platforms/Kconfig
@@ -204,6 +204,14 @@ config PPC_PASEMI_CPUFREQ
This adds the support for frequency switching on PA Semi
PWRficient processors.
+config CPU_FREQ_MAPLE
+ bool "Support for Maple 970FX Evaluation Board"
+ depends on PPC_MAPLE
+ select CPU_FREQ_TABLE
+ help
+ This adds support for frequency switching on Maple 970FX
+ Evaluation Board and compatible boards (IBM JS2x blades).
+
endmenu
config PPC601_SYNC_FIX
diff --git a/arch/powerpc/platforms/maple/Makefile b/arch/powerpc/platforms/maple/Makefile
index 1be1a99..0b3e3e3 100644
--- a/arch/powerpc/platforms/maple/Makefile
+++ b/arch/powerpc/platforms/maple/Makefile
@@ -1 +1,2 @@
obj-y += setup.o pci.o time.o
+obj-$(CONFIG_CPU_FREQ_MAPLE) += cpufreq.o
diff --git a/arch/powerpc/platforms/maple/cpufreq.c b/arch/powerpc/platforms/maple/cpufreq.c
new file mode 100644
index 0000000..1f706c1
--- /dev/null
+++ b/arch/powerpc/platforms/maple/cpufreq.c
@@ -0,0 +1,317 @@
+/*
+ * Copyright (C) 2011 Dmitry Eremin-Solenikov
+ * Copyright (C) 2002 - 2005 Benjamin Herrenschmidt <benh@kernel.crashing.org>
+ * and Markus Demleitner <msdemlei@cl.uni-heidelberg.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This driver adds basic cpufreq support for SMU & 970FX based G5 Macs,
+ * that is iMac G5 and latest single CPU desktop.
+ */
+
+#undef DEBUG
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/sched.h>
+#include <linux/cpufreq.h>
+#include <linux/init.h>
+#include <linux/completion.h>
+#include <linux/mutex.h>
+#include <asm/prom.h>
+#include <asm/machdep.h>
+#include <asm/irq.h>
+#include <asm/sections.h>
+#include <asm/cputable.h>
+#include <asm/time.h>
+
+#define DBG(fmt...) pr_debug(fmt)
+
+/* see 970FX user manual */
+
+#define SCOM_PCR 0x0aa001 /* PCR scom addr */
+
+#define PCR_HILO_SELECT 0x80000000U /* 1 = PCR, 0 = PCRH */
+#define PCR_SPEED_FULL 0x00000000U /* 1:1 speed value */
+#define PCR_SPEED_HALF 0x00020000U /* 1:2 speed value */
+#define PCR_SPEED_QUARTER 0x00040000U /* 1:4 speed value */
+#define PCR_SPEED_MASK 0x000e0000U /* speed mask */
+#define PCR_SPEED_SHIFT 17
+#define PCR_FREQ_REQ_VALID 0x00010000U /* freq request valid */
+#define PCR_VOLT_REQ_VALID 0x00008000U /* volt request valid */
+#define PCR_TARGET_TIME_MASK 0x00006000U /* target time */
+#define PCR_STATLAT_MASK 0x00001f00U /* STATLAT value */
+#define PCR_SNOOPLAT_MASK 0x000000f0U /* SNOOPLAT value */
+#define PCR_SNOOPACC_MASK 0x0000000fU /* SNOOPACC value */
+
+#define SCOM_PSR 0x408001 /* PSR scom addr */
+/* warning: PSR is a 64 bits register */
+#define PSR_CMD_RECEIVED 0x2000000000000000U /* command received */
+#define PSR_CMD_COMPLETED 0x1000000000000000U /* command completed */
+#define PSR_CUR_SPEED_MASK 0x0300000000000000U /* current speed */
+#define PSR_CUR_SPEED_SHIFT (56)
+
+/*
+ * The G5 only supports two frequencies (Quarter speed is not supported)
+ */
+#define CPUFREQ_HIGH 0
+#define CPUFREQ_LOW 1
+
+static struct cpufreq_frequency_table maple_cpu_freqs[] = {
+ {CPUFREQ_HIGH, 0},
+ {CPUFREQ_LOW, 0},
+ {0, CPUFREQ_TABLE_END},
+};
+
+static struct freq_attr* maple_cpu_freqs_attr[] = {
+ &cpufreq_freq_attr_scaling_available_freqs,
+ NULL,
+};
+
+/* Power mode data is an array of the 32 bits PCR values to use for
+ * the various frequencies, retrieved from the device-tree
+ */
+static int maple_pmode_cur;
+
+static DEFINE_MUTEX(maple_switch_mutex);
+
+static const u32 *maple_pmode_data;
+static int maple_pmode_max;
+
+/*
+ * Fake voltage switching for platforms with missing support
+ */
+
+static void maple_dummy_switch_volt(int speed_mode)
+{
+}
+
+/*
+ * SCOM based frequency switching for 970FX rev3
+ */
+static int maple_scom_switch_freq(int speed_mode)
+{
+ unsigned long flags;
+ int to;
+
+ /* If frequency is going up, first ramp up the voltage */
+ if (speed_mode < maple_pmode_cur)
+ maple_dummy_switch_volt(speed_mode);
+
+ local_irq_save(flags);
+
+ /* Clear PCR high */
+ scom970_write(SCOM_PCR, 0);
+ /* Clear PCR low */
+ scom970_write(SCOM_PCR, PCR_HILO_SELECT | 0);
+ /* Set PCR low */
+ scom970_write(SCOM_PCR, PCR_HILO_SELECT |
+ maple_pmode_data[speed_mode]);
+
+ /* Wait for completion */
+ for (to = 0; to < 10; to++) {
+ unsigned long psr = scom970_read(SCOM_PSR);
+
+ if ((psr & PSR_CMD_RECEIVED) == 0 &&
+ (((psr >> PSR_CUR_SPEED_SHIFT) ^
+ (maple_pmode_data[speed_mode] >> PCR_SPEED_SHIFT)) & 0x3)
+ == 0)
+ break;
+ if (psr & PSR_CMD_COMPLETED)
+ break;
+ udelay(100);
+ }
+
+ local_irq_restore(flags);
+
+ /* If frequency is going down, last ramp the voltage */
+ if (speed_mode > maple_pmode_cur)
+ maple_dummy_switch_volt(speed_mode);
+
+ maple_pmode_cur = speed_mode;
+ ppc_proc_freq = maple_cpu_freqs[speed_mode].frequency * 1000ul;
+
+ return 0;
+}
+
+static int maple_scom_query_freq(void)
+{
+ unsigned long psr = scom970_read(SCOM_PSR);
+ int i;
+
+ for (i = 0; i <= maple_pmode_max; i++)
+ if ((((psr >> PSR_CUR_SPEED_SHIFT) ^
+ (maple_pmode_data[i] >> PCR_SPEED_SHIFT)) & 0x3) == 0)
+ break;
+ return i;
+}
+
+/*
+ * Common interface to the cpufreq core
+ */
+
+static int maple_cpufreq_verify(struct cpufreq_policy *policy)
+{
+ return cpufreq_frequency_table_verify(policy, maple_cpu_freqs);
+}
+
+static int maple_cpufreq_target(struct cpufreq_policy *policy,
+ unsigned int target_freq, unsigned int relation)
+{
+ unsigned int newstate = 0;
+ struct cpufreq_freqs freqs;
+ int rc;
+
+ if (cpufreq_frequency_table_target(policy, maple_cpu_freqs,
+ target_freq, relation, &newstate))
+ return -EINVAL;
+
+ if (maple_pmode_cur == newstate)
+ return 0;
+
+ mutex_lock(&maple_switch_mutex);
+
+ freqs.old = maple_cpu_freqs[maple_pmode_cur].frequency;
+ freqs.new = maple_cpu_freqs[newstate].frequency;
+ freqs.cpu = 0;
+
+ cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
+ rc = maple_scom_switch_freq(newstate);
+ cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
+
+ mutex_unlock(&maple_switch_mutex);
+
+ return rc;
+}
+
+static unsigned int maple_cpufreq_get_speed(unsigned int cpu)
+{
+ return maple_cpu_freqs[maple_pmode_cur].frequency;
+}
+
+static int maple_cpufreq_cpu_init(struct cpufreq_policy *policy)
+{
+ policy->cpuinfo.transition_latency = 12000;
+ policy->cur = maple_cpu_freqs[maple_scom_query_freq()].frequency;
+ /* secondary CPUs are tied to the primary one by the
+ * cpufreq core if in the secondary policy we tell it that
+ * it actually must be one policy together with all others. */
+ cpumask_copy(policy->cpus, cpu_online_mask);
+ cpufreq_frequency_table_get_attr(maple_cpu_freqs, policy->cpu);
+
+ return cpufreq_frequency_table_cpuinfo(policy,
+ maple_cpu_freqs);
+}
+
+
+static struct cpufreq_driver maple_cpufreq_driver = {
+ .name = "maple",
+ .owner = THIS_MODULE,
+ .flags = CPUFREQ_CONST_LOOPS,
+ .init = maple_cpufreq_cpu_init,
+ .verify = maple_cpufreq_verify,
+ .target = maple_cpufreq_target,
+ .get = maple_cpufreq_get_speed,
+ .attr = maple_cpu_freqs_attr,
+};
+
+static int __init maple_cpufreq_init(void)
+{
+ struct device_node *cpus;
+ struct device_node *cpunode;
+ unsigned int psize;
+ unsigned long max_freq;
+ const u32 *valp;
+ u32 pvr_hi;
+ int rc = -ENODEV;
+
+ cpus = of_find_node_by_path("/cpus");
+ if (cpus == NULL) {
+ DBG("No /cpus node !\n");
+ return -ENODEV;
+ }
+
+ /* Get first CPU node */
+ for (cpunode = NULL;
+ (cpunode = of_get_next_child(cpus, cpunode)) != NULL;) {
+ const u32 *reg = of_get_property(cpunode, "reg", NULL);
+ if (reg == NULL || (*reg) != 0)
+ continue;
+ if (!strcmp(cpunode->type, "cpu"))
+ break;
+ }
+ if (cpunode == NULL) {
+ printk(KERN_ERR "cpufreq: Can't find any CPU 0 node\n");
+ goto bail_cpus;
+ }
+
+ /* Check 970FX for now */
+ /* we actually don't care on which CPU to access PVR */
+ pvr_hi = PVR_VER(mfspr(SPRN_PVR));
+ if (pvr_hi != 0x3c && pvr_hi != 0x44) {
+ printk(KERN_ERR "cpufreq: Unsupported CPU version (%x)\n", pvr_hi);
+ goto bail_noprops;
+ }
+
+ /* Look for the powertune data in the device-tree */
+ maple_pmode_data = of_get_property(cpunode, "power-mode-data",&psize);
+ if (!maple_pmode_data) {
+ DBG("No power-mode-data !\n");
+ goto bail_noprops;
+ }
+ maple_pmode_max = psize / sizeof(u32) - 1;
+
+ /*
+ * From what I see, clock-frequency is always the maximal frequency.
+ * The current driver can not slew sysclk yet, so we really only deal
+ * with powertune steps for now. We also only implement full freq and
+ * half freq in this version. So far, I haven't yet seen a machine
+ * supporting anything else.
+ */
+ valp = of_get_property(cpunode, "clock-frequency", NULL);
+ if (!valp)
+ return -ENODEV;
+ max_freq = (*valp)/1000;
+ maple_cpu_freqs[0].frequency = max_freq;
+ maple_cpu_freqs[1].frequency = max_freq/2;
+
+ /* Force apply current frequency to make sure everything is in
+ * sync (voltage is right for example). Firmware may leave us with
+ * a strange setting ...
+ */
+ maple_dummy_switch_volt(CPUFREQ_HIGH);
+ msleep(10);
+ maple_pmode_cur = -1;
+ maple_scom_switch_freq(maple_scom_query_freq());
+
+ printk(KERN_INFO "Registering G5 CPU frequency driver\n");
+ printk(KERN_INFO "Frequency method: SCOM, Voltage method: none\n");
+ printk(KERN_INFO "Low: %d Mhz, High: %d Mhz, Cur: %d MHz\n",
+ maple_cpu_freqs[1].frequency/1000,
+ maple_cpu_freqs[0].frequency/1000,
+ maple_cpu_freqs[maple_pmode_cur].frequency/1000);
+
+ rc = cpufreq_register_driver(&maple_cpufreq_driver);
+
+ of_node_put(cpunode);
+ of_node_put(cpus);
+
+ return rc;
+
+bail_noprops:
+ of_node_put(cpunode);
+bail_cpus:
+ of_node_put(cpus);
+
+ return rc;
+}
+
+module_init(maple_cpufreq_init);
+
+
+MODULE_LICENSE("GPL");
--
1.7.5.3
^ permalink raw reply related [flat|nested] 11+ messages in thread* Re: [PATCH] Add cpufreq driver for Momentum Maple boards
2011-06-17 8:49 ` Dmitry Eremin-Solenikov
@ 2011-06-17 9:17 ` Arnd Bergmann
2011-06-17 11:12 ` Dmitry Eremin-Solenikov
0 siblings, 1 reply; 11+ messages in thread
From: Arnd Bergmann @ 2011-06-17 9:17 UTC (permalink / raw)
To: linuxppc-dev; +Cc: Dmitry Eremin-Solenikov, davej, paulus, cpufreq
On Friday 17 June 2011 10:49:16 Dmitry Eremin-Solenikov wrote:
> Add simple cpufreq driver for Maple-based boards (ppc970fx evaluation
> kit and others). Driver is based on a cpufreq driver for 64-bit powermac
> boxes with all pmac-dependant features removed and simple cleanup
> applied.
>
> Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
> ---
> arch/powerpc/kernel/misc_64.S | 4 +-
> arch/powerpc/platforms/Kconfig | 8 +
> arch/powerpc/platforms/maple/Makefile | 1 +
> arch/powerpc/platforms/maple/cpufreq.c | 317 ++++++++++++++++++++++++++++++++
> 4 files changed, 328 insertions(+), 2 deletions(-)
> create mode 100644 arch/powerpc/platforms/maple/cpufreq.c
>
I think new cpufreq drivers should live in drivers/cpufreq, not in arch/. We've
started moving other drivers away from arch/x86 and arch/arm already.
The code itself looks good.
Arnd
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH] Add cpufreq driver for Momentum Maple boards
2011-06-17 9:17 ` Arnd Bergmann
@ 2011-06-17 11:12 ` Dmitry Eremin-Solenikov
2011-06-17 11:52 ` Arnd Bergmann
2011-06-17 20:07 ` Dave Jones
0 siblings, 2 replies; 11+ messages in thread
From: Dmitry Eremin-Solenikov @ 2011-06-17 11:12 UTC (permalink / raw)
To: Arnd Bergmann; +Cc: davej, linuxppc-dev, cpufreq, paulus
Hello,
On 6/17/11, Arnd Bergmann <arnd@arndb.de> wrote:
> On Friday 17 June 2011 10:49:16 Dmitry Eremin-Solenikov wrote:
>> Add simple cpufreq driver for Maple-based boards (ppc970fx evaluation
>> kit and others). Driver is based on a cpufreq driver for 64-bit powermac
>> boxes with all pmac-dependant features removed and simple cleanup
>> applied.
>>
>> Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
>> ---
>> arch/powerpc/kernel/misc_64.S | 4 +-
>> arch/powerpc/platforms/Kconfig | 8 +
>> arch/powerpc/platforms/maple/Makefile | 1 +
>> arch/powerpc/platforms/maple/cpufreq.c | 317
>> ++++++++++++++++++++++++++++++++
>> 4 files changed, 328 insertions(+), 2 deletions(-)
>> create mode 100644 arch/powerpc/platforms/maple/cpufreq.c
>>
>
>
> I think new cpufreq drivers should live in drivers/cpufreq, not in arch/.
> We've
> started moving other drivers away from arch/x86 and arch/arm already.
What about drivers/cpufreq/powerpc, or it's an unnecessary?
Should I resumbit it, or there will be massive arch/powerpc ->
drivers/cpufreq move?
--
With best wishes
Dmitry
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH] Add cpufreq driver for Momentum Maple boards
2011-06-17 11:12 ` Dmitry Eremin-Solenikov
@ 2011-06-17 11:52 ` Arnd Bergmann
2011-06-17 20:07 ` Dave Jones
1 sibling, 0 replies; 11+ messages in thread
From: Arnd Bergmann @ 2011-06-17 11:52 UTC (permalink / raw)
To: Dmitry Eremin-Solenikov; +Cc: davej, linuxppc-dev, cpufreq, paulus
On Friday 17 June 2011 13:12:56 Dmitry Eremin-Solenikov wrote:
> > I think new cpufreq drivers should live in drivers/cpufreq, not in arch/.
> > We've
> > started moving other drivers away from arch/x86 and arch/arm already.
>
> What about drivers/cpufreq/powerpc, or it's an unnecessary?
drivers/cpufreq is fine by itself, unless Dave has some preference.
> Should I resumbit it, or there will be massive arch/powerpc ->
> drivers/cpufreq move?
My recommendation would be to submit the new driver for drivers/cpufreq
directly and let Ben take care of the others at a convenient time.
Arnd
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH] Add cpufreq driver for Momentum Maple boards
2011-06-17 11:12 ` Dmitry Eremin-Solenikov
2011-06-17 11:52 ` Arnd Bergmann
@ 2011-06-17 20:07 ` Dave Jones
1 sibling, 0 replies; 11+ messages in thread
From: Dave Jones @ 2011-06-17 20:07 UTC (permalink / raw)
To: Dmitry Eremin-Solenikov; +Cc: paulus, linuxppc-dev, cpufreq, Arnd Bergmann
On Fri, Jun 17, 2011 at 03:12:56PM +0400, Dmitry Eremin-Solenikov wrote:
> What about drivers/cpufreq/powerpc, or it's an unnecessary?
We haven't done it so far for x86 & arm, so for now at least, just keeping
them in drivers/cpufreq/ should be sufficient.
> Should I resumbit it, or there will be massive arch/powerpc ->
> drivers/cpufreq move?
Good question. I haven't heard anything from any of the PPC maintainers
on this subject, but I'll be happy to help out where I can if they
decide to follow suit with x86/arm.
Dave
^ permalink raw reply [flat|nested] 11+ messages in thread
end of thread, other threads:[~2011-06-17 20:07 UTC | newest]
Thread overview: 11+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2011-05-21 10:28 [PATCH] Add cpufreq driver for Momentum Maple boards Dmitry Eremin-Solenikov
2011-05-30 11:57 ` Dmitry Eremin-Solenikov
2011-06-04 9:00 ` Dmitry Eremin-Solenikov
2011-06-04 10:29 ` Benjamin Herrenschmidt
2011-06-04 10:39 ` Dmitry Eremin-Solenikov
2011-06-17 4:14 ` Benjamin Herrenschmidt
2011-06-17 8:49 ` Dmitry Eremin-Solenikov
2011-06-17 9:17 ` Arnd Bergmann
2011-06-17 11:12 ` Dmitry Eremin-Solenikov
2011-06-17 11:52 ` Arnd Bergmann
2011-06-17 20:07 ` Dave Jones
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