cpufreq: remove sa1100 driver

The sa11xx platform has two cpufreq drivers, one for the older
StrongARM1100 SoC, and a second one for StrongARM1110. After
the removal of most SA1100 based machines, this driver is unused,
and only the sa1110-cpufreq driver remains.
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

drivers/cpufreq/Kconfig

@@ -37,7 +37,7 @@ config CPU_FREQ_STAT
 
 choice
 	prompt "Default CPUFreq governor"
-	default CPU_FREQ_DEFAULT_GOV_USERSPACE if ARM_SA1100_CPUFREQ || ARM_SA1110_CPUFREQ
+	default CPU_FREQ_DEFAULT_GOV_USERSPACE if ARM_SA1110_CPUFREQ
 	default CPU_FREQ_DEFAULT_GOV_SCHEDUTIL if ARM64 || ARM
 	default CPU_FREQ_DEFAULT_GOV_SCHEDUTIL if X86_INTEL_PSTATE && SMP
 	default CPU_FREQ_DEFAULT_GOV_PERFORMANCE

drivers/cpufreq/Kconfig.arm

@@ -286,9 +286,6 @@ config ARM_S5PV210_CPUFREQ
 
 	  If in doubt, say N.
 
-config ARM_SA1100_CPUFREQ
-	bool
-
 config ARM_SA1110_CPUFREQ
 	bool
 

drivers/cpufreq/Makefile

@@ -79,7 +79,6 @@ obj-$(CONFIG_ARM_S3C64XX_CPUFREQ)	+= s3c64xx-cpufreq.o
 obj-$(CONFIG_ARM_S3C24XX_CPUFREQ)	+= s3c24xx-cpufreq.o
 obj-$(CONFIG_ARM_S3C24XX_CPUFREQ_DEBUGFS) += s3c24xx-cpufreq-debugfs.o
 obj-$(CONFIG_ARM_S5PV210_CPUFREQ)	+= s5pv210-cpufreq.o
-obj-$(CONFIG_ARM_SA1100_CPUFREQ)	+= sa1100-cpufreq.o
 obj-$(CONFIG_ARM_SA1110_CPUFREQ)	+= sa1110-cpufreq.o
 obj-$(CONFIG_ARM_SCMI_CPUFREQ)		+= scmi-cpufreq.o
 obj-$(CONFIG_ARM_SCPI_CPUFREQ)		+= scpi-cpufreq.o

drivers/cpufreq/sa1100-cpufreq.c

-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * cpu-sa1100.c: clock scaling for the SA1100
- *
- * Copyright (C) 2000 2001, The Delft University of Technology
- *
- * Authors:
- * - Johan Pouwelse (J.A.Pouwelse@its.tudelft.nl): initial version
- * - Erik Mouw (J.A.K.Mouw@its.tudelft.nl):
- *   - major rewrite for linux-2.3.99
- *   - rewritten for the more generic power management scheme in
- *     linux-2.4.5-rmk1
- *
- * This software has been developed while working on the LART
- * computing board (http://www.lartmaker.nl/), which is
- * sponsored by the Mobile Multi-media Communications
- * (http://www.mobimedia.org/) and Ubiquitous Communications
- * (http://www.ubicom.tudelft.nl/) projects.
- *
- * The authors can be reached at:
- *
- *  Erik Mouw
- *  Information and Communication Theory Group
- *  Faculty of Information Technology and Systems
- *  Delft University of Technology
- *  P.O. Box 5031
- *  2600 GA Delft
- *  The Netherlands
- *
- * Theory of operations
- * ====================
- *
- * Clock scaling can be used to lower the power consumption of the CPU
- * core. This will give you a somewhat longer running time.
- *
- * The SA-1100 has a single register to change the core clock speed:
- *
- *   PPCR      0x90020014    PLL config
- *
- * However, the DRAM timings are closely related to the core clock
- * speed, so we need to change these, too. The used registers are:
- *
- *   MDCNFG    0xA0000000    DRAM config
- *   MDCAS0    0xA0000004    Access waveform
- *   MDCAS1    0xA0000008    Access waveform
- *   MDCAS2    0xA000000C    Access waveform
- *
- * Care must be taken to change the DRAM parameters the correct way,
- * because otherwise the DRAM becomes unusable and the kernel will
- * crash.
- *
- * The simple solution to avoid a kernel crash is to put the actual
- * clock change in ROM and jump to that code from the kernel. The main
- * disadvantage is that the ROM has to be modified, which is not
- * possible on all SA-1100 platforms. Another disadvantage is that
- * jumping to ROM makes clock switching unnecessary complicated.
- *
- * The idea behind this driver is that the memory configuration can be
- * changed while running from DRAM (even with interrupts turned on!)
- * as long as all re-configuration steps yield a valid DRAM
- * configuration. The advantages are clear: it will run on all SA-1100
- * platforms, and the code is very simple.
- *
- * If you really want to understand what is going on in
- * sa1100_update_dram_timings(), you'll have to read sections 8.2,
- * 9.5.7.3, and 10.2 from the "Intel StrongARM SA-1100 Microprocessor
- * Developers Manual" (available for free from Intel).
- */
-
-#include <linux/kernel.h>
-#include <linux/types.h>
-#include <linux/init.h>
-#include <linux/cpufreq.h>
-#include <linux/io.h>
-
-#include <asm/cputype.h>
-
-#include <mach/generic.h>
-#include <mach/hardware.h>
-
-struct sa1100_dram_regs {
-	int speed;
-	u32 mdcnfg;
-	u32 mdcas0;
-	u32 mdcas1;
-	u32 mdcas2;
-};
-
-
-static struct cpufreq_driver sa1100_driver;
-
-static struct sa1100_dram_regs sa1100_dram_settings[] = {
-	/*speed,     mdcnfg,     mdcas0,     mdcas1,     mdcas2,   clock freq */
-	{ 59000, 0x00dc88a3, 0xcccccccf, 0xfffffffc, 0xffffffff},/*  59.0 MHz */
-	{ 73700, 0x011490a3, 0xcccccccf, 0xfffffffc, 0xffffffff},/*  73.7 MHz */
-	{ 88500, 0x014e90a3, 0xcccccccf, 0xfffffffc, 0xffffffff},/*  88.5 MHz */
-	{103200, 0x01889923, 0xcccccccf, 0xfffffffc, 0xffffffff},/* 103.2 MHz */
-	{118000, 0x01c29923, 0x9999998f, 0xfffffff9, 0xffffffff},/* 118.0 MHz */
-	{132700, 0x01fb2123, 0x9999998f, 0xfffffff9, 0xffffffff},/* 132.7 MHz */
-	{147500, 0x02352123, 0x3333330f, 0xfffffff3, 0xffffffff},/* 147.5 MHz */
-	{162200, 0x026b29a3, 0x38e38e1f, 0xfff8e38e, 0xffffffff},/* 162.2 MHz */
-	{176900, 0x02a329a3, 0x71c71c1f, 0xfff1c71c, 0xffffffff},/* 176.9 MHz */
-	{191700, 0x02dd31a3, 0xe38e383f, 0xffe38e38, 0xffffffff},/* 191.7 MHz */
-	{206400, 0x03153223, 0xc71c703f, 0xffc71c71, 0xffffffff},/* 206.4 MHz */
-	{221200, 0x034fba23, 0xc71c703f, 0xffc71c71, 0xffffffff},/* 221.2 MHz */
-	{235900, 0x03853a23, 0xe1e1e07f, 0xe1e1e1e1, 0xffffffe1},/* 235.9 MHz */
-	{250700, 0x03bf3aa3, 0xc3c3c07f, 0xc3c3c3c3, 0xffffffc3},/* 250.7 MHz */
-	{265400, 0x03f7c2a3, 0xc3c3c07f, 0xc3c3c3c3, 0xffffffc3},/* 265.4 MHz */
-	{280200, 0x0431c2a3, 0x878780ff, 0x87878787, 0xffffff87},/* 280.2 MHz */
-	{ 0, 0, 0, 0, 0 } /* last entry */
-};
-
-static void sa1100_update_dram_timings(int current_speed, int new_speed)
-{
-	struct sa1100_dram_regs *settings = sa1100_dram_settings;
-
-	/* find speed */
-	while (settings->speed != 0) {
-		if (new_speed == settings->speed)
-			break;
-
-		settings++;
-	}
-
-	if (settings->speed == 0) {
-		panic("%s: couldn't find dram setting for speed %d\n",
-		      __func__, new_speed);
-	}
-
-	/* No risk, no fun: run with interrupts on! */
-	if (new_speed > current_speed) {
-		/* We're going FASTER, so first relax the memory
-		 * timings before changing the core frequency
-		 */
-
-		/* Half the memory access clock */
-		MDCNFG |= MDCNFG_CDB2;
-
-		/* The order of these statements IS important, keep 8
-		 * pulses!!
-		 */
-		MDCAS2 = settings->mdcas2;
-		MDCAS1 = settings->mdcas1;
-		MDCAS0 = settings->mdcas0;
-		MDCNFG = settings->mdcnfg;
-	} else {
-		/* We're going SLOWER: first decrease the core
-		 * frequency and then tighten the memory settings.
-		 */
-
-		/* Half the memory access clock */
-		MDCNFG |= MDCNFG_CDB2;
-
-		/* The order of these statements IS important, keep 8
-		 * pulses!!
-		 */
-		MDCAS0 = settings->mdcas0;
-		MDCAS1 = settings->mdcas1;
-		MDCAS2 = settings->mdcas2;
-		MDCNFG = settings->mdcnfg;
-	}
-}
-
-static int sa1100_target(struct cpufreq_policy *policy, unsigned int ppcr)
-{
-	unsigned int cur = sa11x0_getspeed(0);
-	unsigned int new_freq;
-
-	new_freq = sa11x0_freq_table[ppcr].frequency;
-
-	if (new_freq > cur)
-		sa1100_update_dram_timings(cur, new_freq);
-
-	PPCR = ppcr;
-
-	if (new_freq < cur)
-		sa1100_update_dram_timings(cur, new_freq);
-
-	return 0;
-}
-
-static int __init sa1100_cpu_init(struct cpufreq_policy *policy)
-{
-	cpufreq_generic_init(policy, sa11x0_freq_table, 0);
-	return 0;
-}
-
-static struct cpufreq_driver sa1100_driver __refdata = {
-	.flags		= CPUFREQ_NEED_INITIAL_FREQ_CHECK |
-			  CPUFREQ_NO_AUTO_DYNAMIC_SWITCHING,
-	.verify		= cpufreq_generic_frequency_table_verify,
-	.target_index	= sa1100_target,
-	.get		= sa11x0_getspeed,
-	.init		= sa1100_cpu_init,
-	.name		= "sa1100",
-};
-
-static int __init sa1100_dram_init(void)
-{
-	if (cpu_is_sa1100())
-		return cpufreq_register_driver(&sa1100_driver);
-	else
-		return -ENODEV;
-}
-
-arch_initcall(sa1100_dram_init);