From 140780ab5a2bc04ccff77337c3a27f3b44182a91 Mon Sep 17 00:00:00 2001 From: Ben Dooks Date: Thu, 30 Jul 2009 23:23:37 +0100 Subject: ARM: S3C24XX: CPUFREQ: S3C2412/S3C2443 IO timing support Add IO bank timing support for S3C2412/S3C2443. Signed-off-by: Ben Dooks Signed-off-by: Ben Dooks --- arch/arm/plat-s3c24xx/Kconfig | 9 + arch/arm/plat-s3c24xx/Makefile | 1 + arch/arm/plat-s3c24xx/include/plat/cpu-freq-core.h | 52 +++- arch/arm/plat-s3c24xx/s3c2412-iotiming.c | 261 +++++++++++++++++++++ 4 files changed, 322 insertions(+), 1 deletion(-) create mode 100644 arch/arm/plat-s3c24xx/s3c2412-iotiming.c (limited to 'arch/arm/plat-s3c24xx') diff --git a/arch/arm/plat-s3c24xx/Kconfig b/arch/arm/plat-s3c24xx/Kconfig index ec9921b6848b..f0b9c73fe008 100644 --- a/arch/arm/plat-s3c24xx/Kconfig +++ b/arch/arm/plat-s3c24xx/Kconfig @@ -157,6 +157,15 @@ config S3C2410_CPUFREQ_UTILS Internal node to select timing code that is common to the s3c2410 and s3c2440/s3c244 cpu frequency support. +# cpu frequency support common to s3c2412, s3c2413 and s3c2442 + +config S3C2412_IOTIMING + bool + depends on CPU_FREQ_S3C24XX && (CPU_S3C2412 || CPU_S3C2443) + help + Intel node to select io timing code that is common to the s3c2412 + and the s3c2443. + config MACH_SMDK bool help diff --git a/arch/arm/plat-s3c24xx/Makefile b/arch/arm/plat-s3c24xx/Makefile index c60317b3491b..8759c070fd9a 100644 --- a/arch/arm/plat-s3c24xx/Makefile +++ b/arch/arm/plat-s3c24xx/Makefile @@ -40,6 +40,7 @@ obj-$(CONFIG_S3C2410_CLOCK) += s3c2410-clock.o obj-$(CONFIG_S3C2410_DMA) += dma.o obj-$(CONFIG_S3C24XX_ADC) += adc.o obj-$(CONFIG_S3C2410_IOTIMING) += s3c2410-iotiming.o +obj-$(CONFIG_S3C2412_IOTIMING) += s3c2412-iotiming.o obj-$(CONFIG_S3C2410_CPUFREQ_UTILS) += s3c2410-cpufreq-utils.o # device specific setup and/or initialisation diff --git a/arch/arm/plat-s3c24xx/include/plat/cpu-freq-core.h b/arch/arm/plat-s3c24xx/include/plat/cpu-freq-core.h index 7938fb0bc387..f02b3c06c1e0 100644 --- a/arch/arm/plat-s3c24xx/include/plat/cpu-freq-core.h +++ b/arch/arm/plat-s3c24xx/include/plat/cpu-freq-core.h @@ -42,8 +42,44 @@ struct s3c2410_iobank_timing { unsigned char nwait_en; /* nWait enabled for bank. */ }; +/** + * struct s3c2412_iobank_timing - io timings for PL092 (S3C2412) style IO + * @idcy: The idle cycle time between transactions. + * @wstrd: nCS release to end of read cycle. + * @wstwr: nCS release to end of write cycle. + * @wstoen: nCS assertion to nOE assertion time. + * @wstwen: nCS assertion to nWE assertion time. + * @wstbrd: Burst ready delay. + * @smbidcyr: Register cache for smbidcyr value. + * @smbwstrd: Register cache for smbwstrd value. + * @smbwstwr: Register cache for smbwstwr value. + * @smbwstoen: Register cache for smbwstoen value. + * @smbwstwen: Register cache for smbwstwen value. + * @smbwstbrd: Register cache for smbwstbrd value. + * + * Timing information for a IO bank on an S3C2412 or similar system which + * uses a PL093 block. + */ +struct s3c2412_iobank_timing { + unsigned int idcy; + unsigned int wstrd; + unsigned int wstwr; + unsigned int wstoen; + unsigned int wstwen; + unsigned int wstbrd; + + /* register cache */ + unsigned char smbidcyr; + unsigned char smbwstrd; + unsigned char smbwstwr; + unsigned char smbwstoen; + unsigned char smbwstwen; + unsigned char smbwstbrd; +}; + union s3c_iobank { - struct s3c2410_iobank_timing *io_2410; + struct s3c2410_iobank_timing *io_2410; + struct s3c2412_iobank_timing *io_2412; }; /** @@ -174,6 +210,20 @@ extern void s3c2410_iotiming_set(struct s3c_cpufreq_config *cfg, extern void s3c2410_set_fvco(struct s3c_cpufreq_config *cfg); +/* S3C2412 compatible routines */ + +extern int s3c2412_iotiming_get(struct s3c_cpufreq_config *cfg, + struct s3c_iotimings *timings); + +extern int s3c2412_iotiming_get(struct s3c_cpufreq_config *cfg, + struct s3c_iotimings *timings); + +extern int s3c2412_iotiming_calc(struct s3c_cpufreq_config *cfg, + struct s3c_iotimings *iot); + +extern void s3c2412_iotiming_set(struct s3c_cpufreq_config *cfg, + struct s3c_iotimings *iot); + #ifdef CONFIG_CPU_FREQ_S3C24XX_DEBUG #define s3c_freq_dbg(x...) printk(KERN_INFO x) #else diff --git a/arch/arm/plat-s3c24xx/s3c2412-iotiming.c b/arch/arm/plat-s3c24xx/s3c2412-iotiming.c new file mode 100644 index 000000000000..a3648cba0eb9 --- /dev/null +++ b/arch/arm/plat-s3c24xx/s3c2412-iotiming.c @@ -0,0 +1,261 @@ +/* linux/arch/arm/plat-s3c24xx/s3c2412-iotiming.c + * + * Copyright (c) 2006,2008 Simtec Electronics + * http://armlinux.simtec.co.uk/ + * Ben Dooks + * + * S3C2412/S3C2443 (PL093 based) IO timing support + * + * 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. +*/ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +#include +#include + +#include + +#include +#include +#include + +#define print_ns(x) ((x) / 10), ((x) % 10) + +/** + * s3c2412_print_timing - print timing infromation via printk. + * @pfx: The prefix to print each line with. + * @iot: The IO timing information + */ +static void s3c2412_print_timing(const char *pfx, struct s3c_iotimings *iot) +{ + struct s3c2412_iobank_timing *bt; + unsigned int bank; + + for (bank = 0; bank < MAX_BANKS; bank++) { + bt = iot->bank[bank].io_2412; + if (!bt) + continue; + + printk(KERN_DEBUG "%s: %d: idcy=%d.%d wstrd=%d.%d wstwr=%d,%d" + "wstoen=%d.%d wstwen=%d.%d wstbrd=%d.%d\n", pfx, bank, + print_ns(bt->idcy), + print_ns(bt->wstrd), + print_ns(bt->wstwr), + print_ns(bt->wstoen), + print_ns(bt->wstwen), + print_ns(bt->wstbrd)); + } +} + +/** + * to_div - turn a cycle length into a divisor setting. + * @cyc_tns: The cycle time in 10ths of nanoseconds. + * @clk_tns: The clock period in 10ths of nanoseconds. + */ +static inline unsigned int to_div(unsigned int cyc_tns, unsigned int clk_tns) +{ + return cyc_tns ? DIV_ROUND_UP(cyc_tns, clk_tns) : 0; +} + +/** + * calc_timing - calculate timing divisor value and check in range. + * @hwtm: The hardware timing in 10ths of nanoseconds. + * @clk_tns: The clock period in 10ths of nanoseconds. + * @err: Pointer to err variable to update in event of failure. + */ +static unsigned int calc_timing(unsigned int hwtm, unsigned int clk_tns, + unsigned int *err) +{ + unsigned int ret = to_div(hwtm, clk_tns); + + if (ret > 0xf) + *err = -EINVAL; + + return ret; +} + +/** + * s3c2412_calc_bank - calculate the bank divisor settings. + * @cfg: The current frequency configuration. + * @bt: The bank timing. + */ +static int s3c2412_calc_bank(struct s3c_cpufreq_config *cfg, + struct s3c2412_iobank_timing *bt) +{ + unsigned int hclk = cfg->freq.hclk_tns; + int err = 0; + + bt->smbidcyr = calc_timing(bt->idcy, hclk, &err); + bt->smbwstrd = calc_timing(bt->wstrd, hclk, &err); + bt->smbwstwr = calc_timing(bt->wstwr, hclk, &err); + bt->smbwstoen = calc_timing(bt->wstoen, hclk, &err); + bt->smbwstwen = calc_timing(bt->wstwen, hclk, &err); + bt->smbwstbrd = calc_timing(bt->wstbrd, hclk, &err); + + return err; +} + +/** + * s3c2412_iotiming_calc - calculate all the bank divisor settings. + * @cfg: The current frequency configuration. + * @iot: The bank timing information. + * + * Calculate the timing information for all the banks that are + * configured as IO, using s3c2412_calc_bank(). + */ +int s3c2412_iotiming_calc(struct s3c_cpufreq_config *cfg, + struct s3c_iotimings *iot) +{ + struct s3c2412_iobank_timing *bt; + int bank; + int ret; + + for (bank = 0; bank < MAX_BANKS; bank++) { + bt = iot->bank[bank].io_2412; + if (!bt) + continue; + + ret = s3c2412_calc_bank(cfg, bt); + if (ret) { + printk(KERN_ERR "%s: cannot calculate bank %d io\n", + __func__, bank); + goto err; + } + } + + return 0; + err: + return ret; +} + +/** + * s3c2412_iotiming_set - set the timing information + * @cfg: The current frequency configuration. + * @iot: The bank timing information. + * + * Set the IO bank information from the details calculated earlier from + * calling s3c2412_iotiming_calc(). + */ +void s3c2412_iotiming_set(struct s3c_cpufreq_config *cfg, + struct s3c_iotimings *iot) +{ + struct s3c2412_iobank_timing *bt; + void __iomem *regs; + int bank; + + /* set the io timings from the specifier */ + + for (bank = 0; bank < MAX_BANKS; bank++) { + bt = iot->bank[bank].io_2412; + if (!bt) + continue; + + regs = S3C2412_SSMC_BANK(bank); + + __raw_writel(bt->smbidcyr, regs + SMBIDCYR); + __raw_writel(bt->smbwstrd, regs + SMBWSTRDR); + __raw_writel(bt->smbwstwr, regs + SMBWSTWRR); + __raw_writel(bt->smbwstoen, regs + SMBWSTOENR); + __raw_writel(bt->smbwstwen, regs + SMBWSTWENR); + __raw_writel(bt->smbwstbrd, regs + SMBWSTBRDR); + } +} + +static inline unsigned int s3c2412_decode_timing(unsigned int clock, u32 reg) +{ + return (reg & 0xf) * clock; +} + +static void s3c2412_iotiming_getbank(struct s3c_cpufreq_config *cfg, + struct s3c2412_iobank_timing *bt, + unsigned int bank) +{ + unsigned long clk = cfg->freq.hclk_tns; /* ssmc clock??? */ + void __iomem *regs = S3C2412_SSMC_BANK(bank); + + bt->idcy = s3c2412_decode_timing(clk, __raw_readl(regs + SMBIDCYR)); + bt->wstrd = s3c2412_decode_timing(clk, __raw_readl(regs + SMBWSTRDR)); + bt->wstoen = s3c2412_decode_timing(clk, __raw_readl(regs + SMBWSTOENR)); + bt->wstwen = s3c2412_decode_timing(clk, __raw_readl(regs + SMBWSTWENR)); + bt->wstbrd = s3c2412_decode_timing(clk, __raw_readl(regs + SMBWSTBRDR)); +} + +/** + * bank_is_io - return true if bank is (possibly) IO. + * @bank: The bank number. + * @bankcfg: The value of S3C2412_EBI_BANKCFG. + */ +static inline bool bank_is_io(unsigned int bank, u32 bankcfg) +{ + if (bank < 2) + return true; + + return !(bankcfg & (1 << bank)); +} + +int s3c2412_iotiming_get(struct s3c_cpufreq_config *cfg, + struct s3c_iotimings *timings) +{ + struct s3c2412_iobank_timing *bt; + u32 bankcfg = __raw_readl(S3C2412_EBI_BANKCFG); + unsigned int bank; + + /* look through all banks to see what is currently set. */ + + for (bank = 0; bank < MAX_BANKS; bank++) { + if (!bank_is_io(bank, bankcfg)) + continue; + + bt = kzalloc(sizeof(struct s3c2412_iobank_timing), GFP_KERNEL); + if (!bt) { + printk(KERN_ERR "%s: no memory for bank\n", __func__); + return -ENOMEM; + } + + timings->bank[bank].io_2412 = bt; + s3c2412_iotiming_getbank(cfg, bt, bank); + } + + s3c2412_print_timing("get", timings); + return 0; +} + +/* this is in here as it is so small, it doesn't currently warrant a file + * to itself. We expect that any s3c24xx needing this is going to also + * need the iotiming support. + */ +void s3c2412_cpufreq_setrefresh(struct s3c_cpufreq_config *cfg) +{ + struct s3c_cpufreq_board *board = cfg->board; + u32 refresh; + + WARN_ON(board == NULL); + + /* Reduce both the refresh time (in ns) and the frequency (in MHz) + * down to ensure that we do not overflow 32 bit numbers. + * + * This should work for HCLK up to 133MHz and refresh period up + * to 30usec. + */ + + refresh = (cfg->freq.hclk / 100) * (board->refresh / 10); + refresh = DIV_ROUND_UP(refresh, (1000 * 1000)); /* apply scale */ + refresh &= ((1 << 16) - 1); + + s3c_freq_dbg("%s: refresh value %u\n", __func__, (unsigned int)refresh); + + __raw_writel(refresh, S3C2412_REFRESH); +} -- cgit v1.2.3