Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751195AbVJDFec (ORCPT ); Tue, 4 Oct 2005 01:34:32 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751196AbVJDFec (ORCPT ); Tue, 4 Oct 2005 01:34:32 -0400 Received: from gate.crashing.org ([63.228.1.57]:35499 "EHLO gate.crashing.org") by vger.kernel.org with ESMTP id S1751195AbVJDFeb (ORCPT ); Tue, 4 Oct 2005 01:34:31 -0400 Subject: [PATCH] ppc64: Add cpufreq support for SMU based G5 From: Benjamin Herrenschmidt To: Andrew Morton Cc: Linux Kernel list , linuxppc64-dev Content-Type: text/plain Date: Tue, 04 Oct 2005 15:30:41 +1000 Message-Id: <1128403842.31063.24.camel@gaston> Mime-Version: 1.0 X-Mailer: Evolution 2.2.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 16294 Lines: 578 iMac G5 and latest single CPU desktop G5 (SMU based machines) have a 970FX DD3 CPU that supports frequency & vooltage switching. This patch adds support for simple dual frequency switch. It is required for the upcoming thermal control patch for these machines. Signed-off-by: Benjamin Herrenschmidt Index: linux-work/arch/ppc64/kernel/misc.S =================================================================== --- linux-work.orig/arch/ppc64/kernel/misc.S 2005-09-23 12:43:21.000000000 +1000 +++ linux-work/arch/ppc64/kernel/misc.S 2005-09-29 17:03:04.000000000 +1000 @@ -616,7 +616,7 @@ isync blr - /* +/* * Do an IO access in real mode */ _GLOBAL(real_writeb) @@ -649,6 +649,76 @@ #endif /* defined(CONFIG_PPC_PMAC) || defined(CONFIG_PPC_MAPLE) */ /* + * SCOM access functions for 970 (FX only for now) + * + * unsigned long scom970_read(unsigned int address); + * void scom970_write(unsigned int address, unsigned long value); + * + * The address passed in is the 24 bits register address. This code + * is 970 specific and will not check the status bits, so you should + * know what you are doing. + */ +_GLOBAL(scom970_read) + /* interrupts off */ + mfmsr r4 + ori r0,r4,MSR_EE + xori r0,r0,MSR_EE + mtmsrd r0,1 + + /* rotate 24 bits SCOM address 8 bits left and mask out it's low 8 bits + * (including parity). On current CPUs they must be 0'd, + * and finally or in RW bit + */ + rlwinm r3,r3,8,0,15 + ori r3,r3,0x8000 + + /* do the actual scom read */ + sync + mtspr SPRN_SCOMC,r3 + isync + mfspr r3,SPRN_SCOMD + isync + mfspr r0,SPRN_SCOMC + isync + + /* XXX: fixup result on some buggy 970's (ouch ! we lost a bit, bah + * that's the best we can do). Not implemented yet as we don't use + * the scom on any of the bogus CPUs yet, but may have to be done + * ultimately + */ + + /* restore interrupts */ + mtmsrd r4,1 + blr + + +_GLOBAL(scom970_write) + /* interrupts off */ + mfmsr r5 + ori r0,r5,MSR_EE + xori r0,r0,MSR_EE + mtmsrd r0,1 + + /* rotate 24 bits SCOM address 8 bits left and mask out it's low 8 bits + * (including parity). On current CPUs they must be 0'd. + */ + + rlwinm r3,r3,8,0,15 + + sync + mtspr SPRN_SCOMD,r4 /* write data */ + isync + mtspr SPRN_SCOMC,r3 /* write command */ + isync + mfspr 3,SPRN_SCOMC + isync + + /* restore interrupts */ + mtmsrd r5,1 + blr + + +/* * Create a kernel thread * kernel_thread(fn, arg, flags) */ Index: linux-work/include/asm-ppc64/processor.h =================================================================== --- linux-work.orig/include/asm-ppc64/processor.h 2005-09-23 12:44:12.000000000 +1000 +++ linux-work/include/asm-ppc64/processor.h 2005-09-27 11:42:50.000000000 +1000 @@ -177,6 +177,9 @@ #define SPRN_CTRLT 0x098 #define CTRL_RUNLATCH 0x1 +#define SPRN_SCOMC 0x114 +#define SPRN_SCOMD 0x115 + /* Performance monitor SPRs */ #define SPRN_SIAR 780 #define SPRN_SDAR 781 @@ -536,6 +539,9 @@ } } +extern unsigned long scom970_read(unsigned int address); +extern void scom970_write(unsigned int address, unsigned long value); + #endif /* __KERNEL__ */ #endif /* __ASSEMBLY__ */ Index: linux-work/arch/ppc64/Kconfig =================================================================== --- linux-work.orig/arch/ppc64/Kconfig 2005-09-23 12:43:21.000000000 +1000 +++ linux-work/arch/ppc64/Kconfig 2005-09-28 10:41:27.000000000 +1000 @@ -159,6 +159,17 @@ support. As of this writing the exact hardware interface is strongly in flux, so no good recommendation can be made. +source "drivers/cpufreq/Kconfig" + +config CPU_FREQ_PMAC + bool "Support for Apple G5" + depends on CPU_FREQ && PPC_PMAC64 + select CPU_FREQ_TABLE + help + This adds support for frequency switching on some Apple G5 + machine. This is currently very experimental and works only + on some iMac G5. + config IBMVIO depends on PPC_PSERIES || PPC_ISERIES bool Index: linux-work/arch/ppc64/kernel/Makefile =================================================================== --- linux-work.orig/arch/ppc64/kernel/Makefile 2005-09-23 12:43:21.000000000 +1000 +++ linux-work/arch/ppc64/kernel/Makefile 2005-09-27 11:42:50.000000000 +1000 @@ -60,6 +60,7 @@ obj-$(CONFIG_PPC_PMAC) += pmac_setup.o pmac_feature.o pmac_pci.o \ pmac_time.o pmac_nvram.o pmac_low_i2c.o \ udbg_scc.o +obj-$(CONFIG_CPU_FREQ_PMAC) += pmac_cpufreq.o obj-$(CONFIG_PPC_MAPLE) += maple_setup.o maple_pci.o maple_time.o \ udbg_16550.o Index: linux-work/arch/ppc64/kernel/pmac_cpufreq.c =================================================================== --- /dev/null 1970-01-01 00:00:00.000000000 +0000 +++ linux-work/arch/ppc64/kernel/pmac_cpufreq.c 2005-09-27 11:42:50.000000000 +1000 @@ -0,0 +1,297 @@ +/* + * Copyright (C) 2002 - 2005 Benjamin Herrenschmidt + * and Markus Demleitner + * + * 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. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#undef DEBUG + +#ifdef DEBUG +#define DBG(fmt...) printk(fmt) +#else +#define DBG(fmt...) +#endif + +/* 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, retreived from the device-tree + */ +static u32 *g5_pmode_data; +static int g5_pmode_max; +static int g5_pmode_cur; + + +static struct smu_sdbp_fvt *g5_fvt_table; /* table of op. points */ +static int g5_fvt_count; /* number of op. points */ +static int g5_fvt_cur; /* current op. point */ + +/* ----------------- real hardware interface */ + +static void g5_switch_volt(int speed_mode) +{ + struct smu_simple_cmd cmd; + + DECLARE_COMPLETION(comp); + smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 8, smu_done_complete, + &comp, 'V', 'S', 'L', 'E', 'W', + 0xff, g5_fvt_cur+1, speed_mode); + wait_for_completion(&comp); +} + +static int g5_switch_freq(int speed_mode) +{ + int to; + + if (g5_pmode_cur == speed_mode) + return 0; + + /* If frequency is going up, first ramp up the voltage */ + if (speed_mode < g5_pmode_cur) + g5_switch_volt(speed_mode); + + /* 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); + } + + /* If frequency is going down, last ramp the voltage */ + if (speed_mode > g5_pmode_cur) + g5_switch_volt(speed_mode); + + g5_pmode_cur = speed_mode; + ppc_proc_freq = g5_cpu_freqs[speed_mode].frequency * 1000ul; + + return 0; +} + +static int g5_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; +} + +/* ----------------- cpufreq bookkeeping */ +static int __pmac g5_cpufreq_verify(struct cpufreq_policy *policy) +{ + return cpufreq_frequency_table_verify(policy, g5_cpu_freqs); +} + +static int __pmac g5_cpufreq_target(struct cpufreq_policy *policy, + unsigned int target_freq, unsigned int relation) +{ + unsigned int newstate = 0; + + if (cpufreq_frequency_table_target(policy, g5_cpu_freqs, + target_freq, relation, &newstate)) + return -EINVAL; + + return g5_switch_freq(newstate); +} + +static int __pmac g5_cpufreq_cpu_init(struct cpufreq_policy *policy) +{ + if (policy->cpu != 0) + return -ENODEV; + + policy->governor = CPUFREQ_DEFAULT_GOVERNOR; + policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL; + policy->cur = g5_cpu_freqs[g5_query_freq()].frequency; + 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 = "powermac", + .owner = THIS_MODULE, + .flags = CPUFREQ_CONST_LOOPS, + .init = g5_cpufreq_cpu_init, + .verify = g5_cpufreq_verify, + .target = g5_cpufreq_target, + .attr = g5_cpu_freqs_attr, +}; + + +static int __init g5_cpufreq_init(void) +{ + struct device_node *cpunode; + unsigned int psize, ssize; + struct smu_sdbp_header *shdr; + unsigned long max_freq; + u32 *valp; + int rc = -ENODEV; + + /* Look for CPU and SMU nodes */ + cpunode = of_find_node_by_type(NULL, "cpu"); + if (!cpunode) { + DBG("No CPU node !\n"); + return -ENODEV; + } + + /* Check 970FX for now */ + valp = (u32 *)get_property(cpunode, "cpu-version", NULL); + if (!valp) { + DBG("No cpu-version property !\n"); + goto bail_noprops; + } + if (((*valp) >> 16) != 0x3c) { + DBG("Wrong CPU version: %08x\n", *valp); + goto bail_noprops; + } + + /* Look for the powertune data in the device-tree */ + g5_pmode_data = (u32 *)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; + + /* Look for the FVT table */ + shdr = smu_get_sdb_partition(SMU_SDB_FVT_ID, NULL); + if (!shdr) + goto bail_noprops; + g5_fvt_table = (struct smu_sdbp_fvt *)&shdr[1]; + ssize = (shdr->len * sizeof(u32)) - sizeof(struct smu_sdbp_header); + g5_fvt_count = ssize / sizeof(struct smu_sdbp_fvt); + g5_fvt_cur = 0; + + /* Sanity checking */ + if (g5_fvt_count < 1 || g5_pmode_max < 1) + goto bail_noprops; + + /* + * 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 = (u32 *)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; + + /* Check current frequency */ + g5_pmode_cur = g5_query_freq(); + if (g5_pmode_cur > 1) { + /* We don't support anything but 1:1 and 1:2, fixup ... */ + g5_switch_freq(1); + g5_pmode_cur = 1; + } + + printk(KERN_INFO "Registering G5 CPU frequency driver\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); + + /* We keep the CPU node on hold... hopefully, Apple G5 don't have + * hotplug CPU with a dynamic device-tree ... + */ + return rc; + + bail_noprops: + of_node_put(cpunode); + + return rc; +} + +module_init(g5_cpufreq_init); + + +MODULE_LICENSE("GPL"); Index: linux-work/drivers/macintosh/smu.c =================================================================== --- linux-work.orig/drivers/macintosh/smu.c 2005-09-26 11:48:36.000000000 +1000 +++ linux-work/drivers/macintosh/smu.c 2005-09-29 16:56:59.000000000 +1000 @@ -843,6 +843,18 @@ return 0; } +struct smu_sdbp_header *smu_get_sdb_partition(int id, unsigned int *size) +{ + char pname[32]; + + if (!smu) + return NULL; + + sprintf(pname, "sdb-partition-%02x", id); + return (struct smu_sdbp_header *)get_property(smu->of_node, + pname, size); +} +EXPORT_SYMBOL(smu_get_sdb_partition); /* Index: linux-work/include/asm-ppc64/smu.h =================================================================== --- linux-work.orig/include/asm-ppc64/smu.h 2005-09-26 11:48:37.000000000 +1000 +++ linux-work/include/asm-ppc64/smu.h 2005-09-29 16:56:59.000000000 +1000 @@ -144,7 +144,11 @@ * - lenght 8 ("VSLEWxyz") has 3 additional bytes appended, and is * used to set the voltage slewing point. The SMU replies with "DONE" * I yet have to figure out their exact meaning of those 3 bytes in - * both cases. + * both cases. They seem to be: + * x = processor mask + * y = op. point index + * z = processor freq. step index + * I haven't yet decyphered result codes * */ #define SMU_CMD_POWER_COMMAND 0xaa @@ -244,6 +248,7 @@ */ extern void smu_done_complete(struct smu_cmd *cmd, void *misc); + /* * Synchronous helpers. Will spin-wait for completion of a command */ @@ -334,6 +339,59 @@ #endif /* __KERNEL__ */ /* + * - SMU "sdb" partitions informations - + */ + + +/* + * Partition header format + */ +struct smu_sdbp_header { + __u8 id; + __u8 len; + __u8 version; + __u8 flags; +}; + +/* + * 32 bits integers are usually encoded with 2x16 bits swapped, + * this demangles them + */ +#define SMU_U32_MIX(x) ((((x) << 16) & 0xffff0000u) | (((x) >> 16) & 0xffffu)) + +/* This is the definition of the SMU sdb-partition-0x12 table (called + * CPU F/V/T operating points in Darwin). The definition for all those + * SMU tables should be moved to some separate file + */ +#define SMU_SDB_FVT_ID 0x12 + +struct smu_sdbp_fvt { + __u32 sysclk; /* Base SysClk frequency in Hz for + * this operating point + */ + __u8 pad; + __u8 maxtemp; /* Max temp. supported by this + * operating point + */ + + __u16 volts[3]; /* CPU core voltage for the 3 + * PowerTune modes, a mode with + * 0V = not supported. + */ +}; + +#ifdef __KERNEL__ +/* + * This returns the pointer to an SMU "sdb" partition data or NULL + * if not found. The data format is described below + */ +extern struct smu_sdbp_header *smu_get_sdb_partition(int id, + unsigned int *size); + +#endif /* __KERNEL__ */ + + +/* * - Userland interface - */ @@ -376,4 +434,5 @@ __u32 reply_len; /* Lenght of data follwing */ }; + #endif /* _SMU_H */ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/