1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Hardware parameter area specific to Sharp SL series devices 4 * 5 * Copyright (c) 2005 Richard Purdie 6 * 7 * Based on Sharp's 2.4 kernel patches 8 */ 9 10 #include <linux/kernel.h> 11 #include <linux/module.h> 12 #include <linux/string.h> 13 #include <asm/mach/sharpsl_param.h> 14 #include <asm/memory.h> 15 16 /* 17 * Certain hardware parameters determined at the time of device manufacture, 18 * typically including LCD parameters are loaded by the bootloader at the 19 * address PARAM_BASE. As the kernel will overwrite them, we need to store 20 * them early in the boot process, then pass them to the appropriate drivers. 21 * Not all devices use all parameters but the format is common to all. 22 */ 23 #ifdef CONFIG_ARCH_SA1100 24 #define PARAM_BASE 0xe8ffc000 25 #define param_start(x) (void *)(x) 26 #else 27 #define PARAM_BASE 0xa0000a00 28 #define param_start(x) __va(x) 29 #endif 30 #define MAGIC_CHG(a,b,c,d) ( ( d << 24 ) | ( c << 16 ) | ( b << 8 ) | a ) 31 32 #define COMADJ_MAGIC MAGIC_CHG('C','M','A','D') 33 #define UUID_MAGIC MAGIC_CHG('U','U','I','D') 34 #define TOUCH_MAGIC MAGIC_CHG('T','U','C','H') 35 #define AD_MAGIC MAGIC_CHG('B','V','A','D') 36 #define PHAD_MAGIC MAGIC_CHG('P','H','A','D') 37 38 struct sharpsl_param_info sharpsl_param; 39 EXPORT_SYMBOL(sharpsl_param); 40 41 void sharpsl_save_param(void) 42 { 43 struct sharpsl_param_info *params = param_start(PARAM_BASE); 44 45 memcpy(&sharpsl_param, params, sizeof(*params)); 46 47 if (sharpsl_param.comadj_keyword != COMADJ_MAGIC) 48 sharpsl_param.comadj=-1; 49 50 if (sharpsl_param.phad_keyword != PHAD_MAGIC) 51 sharpsl_param.phadadj=-1; 52 53 if (sharpsl_param.uuid_keyword != UUID_MAGIC) 54 sharpsl_param.uuid[0]=-1; 55 56 if (sharpsl_param.touch_keyword != TOUCH_MAGIC) 57 sharpsl_param.touch_xp=-1; 58 59 if (sharpsl_param.adadj_keyword != AD_MAGIC) 60 sharpsl_param.adadj=-1; 61 } 62 63 64