[PATCH v2] cpufreq: elanfreq: Drop support for AMD Elan SC4*

[Sean Young <sean@mess.org>]

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 <sean@mess.org>
---
Changes since v1:
 - Also removes elanfreq= entry from kernel-parameters.txt

 .../admin-guide/kernel-parameters.txt         |   4 -
 drivers/cpufreq/Kconfig.x86                   |  15 --
 drivers/cpufreq/Makefile                      |   1 -
 drivers/cpufreq/elanfreq.c                    | 226 ------------------
 4 files changed, 246 deletions(-)
 delete mode 100644 drivers/cpufreq/elanfreq.c

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 4d0f545fb3ec..7ab0e58c4aa9 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 865b290b01ff..c42dd39e0b2a 100644
--- a/drivers/cpufreq/Kconfig.x86
+++ b/drivers/cpufreq/Kconfig.x86
@@ -126,21 +126,6 @@ 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 <file:Documentation/cpu-freq/>.
-
-	  If in doubt, say N.
-
 config X86_POWERNOW_K6
 	tristate "AMD Mobile K6-2/K6-3 PowerNow!"
 	depends on X86_32
diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile
index 96196edf79d5..6c7a39b7f8d2 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_X86_LONGRUN)		+= longrun.o
 obj-$(CONFIG_X86_GX_SUSPMOD)		+= gx-suspmod.o
 obj-$(CONFIG_X86_SPEEDSTEP_ICH)		+= speedstep-ich.o
diff --git a/drivers/cpufreq/elanfreq.c b/drivers/cpufreq/elanfreq.c
deleted file mode 100644
index fc5a58088b35..000000000000
--- 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 <r.schwebel@pengutronix.de>
- *
- *	Parts of this code are (c) Sven Geggus <sven@geggus.net>
- *
- *      All Rights Reserved.
- *
- *	2002-02-13: - initial revision for 2.4.18-pre9 by Robert Schwebel
- */
-
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/init.h>
-
-#include <linux/delay.h>
-#include <linux/cpufreq.h>
-
-#include <asm/cpu_device_id.h>
-#include <linux/timex.h>
-#include <linux/io.h>
-
-#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 <r.schwebel@pengutronix.de>, "
-		"Sven Geggus <sven@geggus.net>");
-MODULE_DESCRIPTION("cpufreq driver for AMD's Elan CPUs");
-
-module_init(elanfreq_init);
-module_exit(elanfreq_exit);
-- 
2.54.0