summaryrefslogtreecommitdiff
path: root/arch/arm/mach-s3c24xx/clock-s3c2443.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm/mach-s3c24xx/clock-s3c2443.c')
-rw-r--r--arch/arm/mach-s3c24xx/clock-s3c2443.c215
1 files changed, 215 insertions, 0 deletions
diff --git a/arch/arm/mach-s3c24xx/clock-s3c2443.c b/arch/arm/mach-s3c24xx/clock-s3c2443.c
new file mode 100644
index 000000000000..efb3ac359566
--- /dev/null
+++ b/arch/arm/mach-s3c24xx/clock-s3c2443.c
@@ -0,0 +1,215 @@
+/* linux/arch/arm/mach-s3c2443/clock.c
+ *
+ * Copyright (c) 2007, 2010 Simtec Electronics
+ * Ben Dooks <ben@simtec.co.uk>
+ *
+ * S3C2443 Clock control support
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+*/
+
+#include <linux/init.h>
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/device.h>
+#include <linux/clk.h>
+#include <linux/mutex.h>
+#include <linux/serial_core.h>
+#include <linux/io.h>
+
+#include <asm/mach/map.h>
+
+#include <mach/hardware.h>
+
+#include <mach/regs-s3c2443-clock.h>
+
+#include <plat/cpu-freq.h>
+
+#include <plat/s3c2443.h>
+#include <plat/clock.h>
+#include <plat/clock-clksrc.h>
+#include <plat/cpu.h>
+
+/* We currently have to assume that the system is running
+ * from the XTPll input, and that all ***REFCLKs are being
+ * fed from it, as we cannot read the state of OM[4] from
+ * software.
+ *
+ * It would be possible for each board initialisation to
+ * set the correct muxing at initialisation
+*/
+
+/* clock selections */
+
+/* armdiv
+ *
+ * this clock is sourced from msysclk and can have a number of
+ * divider values applied to it to then be fed into armclk.
+ * The real clock definition is done in s3c2443-clock.c,
+ * only the armdiv divisor table must be defined here.
+*/
+
+static unsigned int armdiv[16] = {
+ [S3C2443_CLKDIV0_ARMDIV_1 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 1,
+ [S3C2443_CLKDIV0_ARMDIV_2 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 2,
+ [S3C2443_CLKDIV0_ARMDIV_3 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 3,
+ [S3C2443_CLKDIV0_ARMDIV_4 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 4,
+ [S3C2443_CLKDIV0_ARMDIV_6 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 6,
+ [S3C2443_CLKDIV0_ARMDIV_8 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 8,
+ [S3C2443_CLKDIV0_ARMDIV_12 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 12,
+ [S3C2443_CLKDIV0_ARMDIV_16 >> S3C2443_CLKDIV0_ARMDIV_SHIFT] = 16,
+};
+
+/* hsspi
+ *
+ * high-speed spi clock, sourced from esysclk
+*/
+
+static struct clksrc_clk clk_hsspi = {
+ .clk = {
+ .name = "hsspi-if",
+ .parent = &clk_esysclk.clk,
+ .ctrlbit = S3C2443_SCLKCON_HSSPICLK,
+ .enable = s3c2443_clkcon_enable_s,
+ },
+ .reg_div = { .reg = S3C2443_CLKDIV1, .size = 2, .shift = 4 },
+};
+
+
+/* clk_hsmcc_div
+ *
+ * this clock is sourced from epll, and is fed through a divider,
+ * to a mux controlled by sclkcon where either it or a extclk can
+ * be fed to the hsmmc block
+*/
+
+static struct clksrc_clk clk_hsmmc_div = {
+ .clk = {
+ .name = "hsmmc-div",
+ .devname = "s3c-sdhci.1",
+ .parent = &clk_esysclk.clk,
+ },
+ .reg_div = { .reg = S3C2443_CLKDIV1, .size = 2, .shift = 6 },
+};
+
+static int s3c2443_setparent_hsmmc(struct clk *clk, struct clk *parent)
+{
+ unsigned long clksrc = __raw_readl(S3C2443_SCLKCON);
+
+ clksrc &= ~(S3C2443_SCLKCON_HSMMCCLK_EXT |
+ S3C2443_SCLKCON_HSMMCCLK_EPLL);
+
+ if (parent == &clk_epll)
+ clksrc |= S3C2443_SCLKCON_HSMMCCLK_EPLL;
+ else if (parent == &clk_ext)
+ clksrc |= S3C2443_SCLKCON_HSMMCCLK_EXT;
+ else
+ return -EINVAL;
+
+ if (clk->usage > 0) {
+ __raw_writel(clksrc, S3C2443_SCLKCON);
+ }
+
+ clk->parent = parent;
+ return 0;
+}
+
+static int s3c2443_enable_hsmmc(struct clk *clk, int enable)
+{
+ return s3c2443_setparent_hsmmc(clk, clk->parent);
+}
+
+static struct clk clk_hsmmc = {
+ .name = "hsmmc-if",
+ .devname = "s3c-sdhci.1",
+ .parent = &clk_hsmmc_div.clk,
+ .enable = s3c2443_enable_hsmmc,
+ .ops = &(struct clk_ops) {
+ .set_parent = s3c2443_setparent_hsmmc,
+ },
+};
+
+/* standard clock definitions */
+
+static struct clk init_clocks_off[] = {
+ {
+ .name = "sdi",
+ .parent = &clk_p,
+ .enable = s3c2443_clkcon_enable_p,
+ .ctrlbit = S3C2443_PCLKCON_SDI,
+ }, {
+ .name = "spi",
+ .devname = "s3c2410-spi.0",
+ .parent = &clk_p,
+ .enable = s3c2443_clkcon_enable_p,
+ .ctrlbit = S3C2443_PCLKCON_SPI0,
+ }, {
+ .name = "spi",
+ .devname = "s3c2410-spi.1",
+ .parent = &clk_p,
+ .enable = s3c2443_clkcon_enable_p,
+ .ctrlbit = S3C2443_PCLKCON_SPI1,
+ }
+};
+
+/* clocks to add straight away */
+
+static struct clksrc_clk *clksrcs[] __initdata = {
+ &clk_hsspi,
+ &clk_hsmmc_div,
+};
+
+static struct clk *clks[] __initdata = {
+ &clk_hsmmc,
+};
+
+void __init s3c2443_init_clocks(int xtal)
+{
+ unsigned long epllcon = __raw_readl(S3C2443_EPLLCON);
+ int ptr;
+
+ clk_epll.rate = s3c2443_get_epll(epllcon, xtal);
+ clk_epll.parent = &clk_epllref.clk;
+
+ s3c2443_common_init_clocks(xtal, s3c2443_get_mpll,
+ armdiv, ARRAY_SIZE(armdiv),
+ S3C2443_CLKDIV0_ARMDIV_MASK);
+
+ s3c24xx_register_clocks(clks, ARRAY_SIZE(clks));
+
+ for (ptr = 0; ptr < ARRAY_SIZE(clksrcs); ptr++)
+ s3c_register_clksrc(clksrcs[ptr], 1);
+
+ /* We must be careful disabling the clocks we are not intending to
+ * be using at boot time, as subsystems such as the LCD which do
+ * their own DMA requests to the bus can cause the system to lockup
+ * if they where in the middle of requesting bus access.
+ *
+ * Disabling the LCD clock if the LCD is active is very dangerous,
+ * and therefore the bootloader should be careful to not enable
+ * the LCD clock if it is not needed.
+ */
+
+ /* install (and disable) the clocks we do not need immediately */
+
+ s3c_register_clocks(init_clocks_off, ARRAY_SIZE(init_clocks_off));
+ s3c_disable_clocks(init_clocks_off, ARRAY_SIZE(init_clocks_off));
+
+ s3c_pwmclk_init();
+}