From: Sean Young Date: Thu, 7 May 2026 09:01:04 +0000 (+0100) Subject: cpufreq: elanfreq: Drop support for AMD Elan SC4* X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6fb302d2109c84d33e988d5b6e803dc8eae6e21e;p=thirdparty%2Fkernel%2Flinux.git cpufreq: elanfreq: Drop support for AMD Elan SC4* Since commit 8b793a92d862 ("x86/cpu: Remove M486/M486SX/ELAN support"), the AMD Elan SC4* is no longer supported, so the CPU frequency driver is no longer needed. Signed-off-by: Sean Young Reviewed-by: Zhongqiu Han Acked-by: Viresh Kumar [ rjw: Changelog tweaks ] Link: https://patch.msgid.link/20260507090107.10113-1-sean@mess.org Signed-off-by: Rafael J. Wysocki --- diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 4d0f545fb3ec5..7ab0e58c4aa91 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1669,10 +1669,6 @@ Kernel parameters very early in the boot process. For early debugging via a serial port see kgdboc_earlycon instead. - elanfreq= [X86-32] - See comment before function elanfreq_setup() in - arch/x86/kernel/cpu/cpufreq/elanfreq.c. - elfcorehdr=[size[KMG]@]offset[KMG] [PPC,SH,X86,S390,EARLY] Specifies physical address of start of kernel core image elf header and optionally the size. Generally diff --git a/drivers/cpufreq/Kconfig.x86 b/drivers/cpufreq/Kconfig.x86 index 865099926577c..46b9742a16882 100644 --- a/drivers/cpufreq/Kconfig.x86 +++ b/drivers/cpufreq/Kconfig.x86 @@ -113,21 +113,6 @@ config X86_ACPI_CPUFREQ_CPB By enabling this option the acpi_cpufreq driver provides the old entry in addition to the new boost ones, for compatibility reasons. -config ELAN_CPUFREQ - tristate "AMD Elan SC400 and SC410" - depends on MELAN - help - This adds the CPUFreq driver for AMD Elan SC400 and SC410 - processors. - - You need to specify the processor maximum speed as boot - parameter: elanfreq=maxspeed (in kHz) or as module - parameter "max_freq". - - For details, take a look at . - - If in doubt, say N. - config SC520_CPUFREQ tristate "AMD Elan SC520" depends on MELAN diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile index 385c9fcc65c62..8056b8f2200bd 100644 --- a/drivers/cpufreq/Makefile +++ b/drivers/cpufreq/Makefile @@ -40,7 +40,6 @@ obj-$(CONFIG_X86_POWERNOW_K6) += powernow-k6.o obj-$(CONFIG_X86_POWERNOW_K7) += powernow-k7.o obj-$(CONFIG_X86_LONGHAUL) += longhaul.o obj-$(CONFIG_X86_E_POWERSAVER) += e_powersaver.o -obj-$(CONFIG_ELAN_CPUFREQ) += elanfreq.o obj-$(CONFIG_SC520_CPUFREQ) += sc520_freq.o obj-$(CONFIG_X86_LONGRUN) += longrun.o obj-$(CONFIG_X86_GX_SUSPMOD) += gx-suspmod.o diff --git a/drivers/cpufreq/elanfreq.c b/drivers/cpufreq/elanfreq.c deleted file mode 100644 index fc5a58088b35c..0000000000000 --- a/drivers/cpufreq/elanfreq.c +++ /dev/null @@ -1,226 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-or-later -/* - * elanfreq: cpufreq driver for the AMD ELAN family - * - * (c) Copyright 2002 Robert Schwebel - * - * Parts of this code are (c) Sven Geggus - * - * All Rights Reserved. - * - * 2002-02-13: - initial revision for 2.4.18-pre9 by Robert Schwebel - */ - -#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt - -#include -#include -#include - -#include -#include - -#include -#include -#include - -#define REG_CSCIR 0x22 /* Chip Setup and Control Index Register */ -#define REG_CSCDR 0x23 /* Chip Setup and Control Data Register */ - -/* Module parameter */ -static int max_freq; - -struct s_elan_multiplier { - int clock; /* frequency in kHz */ - int val40h; /* PMU Force Mode register */ - int val80h; /* CPU Clock Speed Register */ -}; - -/* - * It is important that the frequencies - * are listed in ascending order here! - */ -static struct s_elan_multiplier elan_multiplier[] = { - {1000, 0x02, 0x18}, - {2000, 0x02, 0x10}, - {4000, 0x02, 0x08}, - {8000, 0x00, 0x00}, - {16000, 0x00, 0x02}, - {33000, 0x00, 0x04}, - {66000, 0x01, 0x04}, - {99000, 0x01, 0x05} -}; - -static struct cpufreq_frequency_table elanfreq_table[] = { - {0, 0, 1000}, - {0, 1, 2000}, - {0, 2, 4000}, - {0, 3, 8000}, - {0, 4, 16000}, - {0, 5, 33000}, - {0, 6, 66000}, - {0, 7, 99000}, - {0, 0, CPUFREQ_TABLE_END}, -}; - - -/** - * elanfreq_get_cpu_frequency: determine current cpu speed - * - * Finds out at which frequency the CPU of the Elan SOC runs - * at the moment. Frequencies from 1 to 33 MHz are generated - * the normal way, 66 and 99 MHz are called "Hyperspeed Mode" - * and have the rest of the chip running with 33 MHz. - */ - -static unsigned int elanfreq_get_cpu_frequency(unsigned int cpu) -{ - u8 clockspeed_reg; /* Clock Speed Register */ - - local_irq_disable(); - outb_p(0x80, REG_CSCIR); - clockspeed_reg = inb_p(REG_CSCDR); - local_irq_enable(); - - if ((clockspeed_reg & 0xE0) == 0xE0) - return 0; - - /* Are we in CPU clock multiplied mode (66/99 MHz)? */ - if ((clockspeed_reg & 0xE0) == 0xC0) { - if ((clockspeed_reg & 0x01) == 0) - return 66000; - else - return 99000; - } - - /* 33 MHz is not 32 MHz... */ - if ((clockspeed_reg & 0xE0) == 0xA0) - return 33000; - - return (1<<((clockspeed_reg & 0xE0) >> 5)) * 1000; -} - - -static int elanfreq_target(struct cpufreq_policy *policy, - unsigned int state) -{ - /* - * Access to the Elan's internal registers is indexed via - * 0x22: Chip Setup & Control Register Index Register (CSCI) - * 0x23: Chip Setup & Control Register Data Register (CSCD) - * - */ - - /* - * 0x40 is the Power Management Unit's Force Mode Register. - * Bit 6 enables Hyperspeed Mode (66/100 MHz core frequency) - */ - - local_irq_disable(); - outb_p(0x40, REG_CSCIR); /* Disable hyperspeed mode */ - outb_p(0x00, REG_CSCDR); - local_irq_enable(); /* wait till internal pipelines and */ - udelay(1000); /* buffers have cleaned up */ - - local_irq_disable(); - - /* now, set the CPU clock speed register (0x80) */ - outb_p(0x80, REG_CSCIR); - outb_p(elan_multiplier[state].val80h, REG_CSCDR); - - /* now, the hyperspeed bit in PMU Force Mode Register (0x40) */ - outb_p(0x40, REG_CSCIR); - outb_p(elan_multiplier[state].val40h, REG_CSCDR); - udelay(10000); - local_irq_enable(); - - return 0; -} -/* - * Module init and exit code - */ - -static int elanfreq_cpu_init(struct cpufreq_policy *policy) -{ - struct cpuinfo_x86 *c = &cpu_data(0); - struct cpufreq_frequency_table *pos; - - /* capability check */ - if ((c->x86_vendor != X86_VENDOR_AMD) || - (c->x86 != 4) || (c->x86_model != 10)) - return -ENODEV; - - /* max freq */ - if (!max_freq) - max_freq = elanfreq_get_cpu_frequency(0); - - /* table init */ - cpufreq_for_each_entry(pos, elanfreq_table) - if (pos->frequency > max_freq) - pos->frequency = CPUFREQ_ENTRY_INVALID; - - policy->freq_table = elanfreq_table; - return 0; -} - - -#ifndef MODULE -/** - * elanfreq_setup - elanfreq command line parameter parsing - * - * elanfreq command line parameter. Use: - * elanfreq=66000 - * to set the maximum CPU frequency to 66 MHz. Note that in - * case you do not give this boot parameter, the maximum - * frequency will fall back to _current_ CPU frequency which - * might be lower. If you build this as a module, use the - * max_freq module parameter instead. - */ -static int __init elanfreq_setup(char *str) -{ - max_freq = simple_strtoul(str, &str, 0); - pr_warn("You're using the deprecated elanfreq command line option. Use elanfreq.max_freq instead, please!\n"); - return 1; -} -__setup("elanfreq=", elanfreq_setup); -#endif - - -static struct cpufreq_driver elanfreq_driver = { - .get = elanfreq_get_cpu_frequency, - .flags = CPUFREQ_NO_AUTO_DYNAMIC_SWITCHING, - .verify = cpufreq_generic_frequency_table_verify, - .target_index = elanfreq_target, - .init = elanfreq_cpu_init, - .name = "elanfreq", -}; - -static const struct x86_cpu_id elan_id[] = { - X86_MATCH_VENDOR_FAM_MODEL(AMD, 4, 10, NULL), - {} -}; -MODULE_DEVICE_TABLE(x86cpu, elan_id); - -static int __init elanfreq_init(void) -{ - if (!x86_match_cpu(elan_id)) - return -ENODEV; - return cpufreq_register_driver(&elanfreq_driver); -} - - -static void __exit elanfreq_exit(void) -{ - cpufreq_unregister_driver(&elanfreq_driver); -} - - -module_param(max_freq, int, 0444); - -MODULE_LICENSE("GPL"); -MODULE_AUTHOR("Robert Schwebel , " - "Sven Geggus "); -MODULE_DESCRIPTION("cpufreq driver for AMD's Elan CPUs"); - -module_init(elanfreq_init); -module_exit(elanfreq_exit);