summaryrefslogtreecommitdiffstats
path: root/arch/arm/mach-shmobile/clock-emev2.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm/mach-shmobile/clock-emev2.c')
-rw-r--r--arch/arm/mach-shmobile/clock-emev2.c249
1 files changed, 249 insertions, 0 deletions
diff --git a/arch/arm/mach-shmobile/clock-emev2.c b/arch/arm/mach-shmobile/clock-emev2.c
new file mode 100644
index 0000000..4710f18
--- /dev/null
+++ b/arch/arm/mach-shmobile/clock-emev2.c
@@ -0,0 +1,249 @@
+/*
+ * Emma Mobile EV2 clock framework support
+ *
+ * Copyright (C) 2012 Magnus Damm
+ *
+ * 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; version 2 of the License.
+ *
+ * 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/io.h>
+#include <linux/sh_clk.h>
+#include <linux/clkdev.h>
+#include <mach/common.h>
+
+#define EMEV2_SMU_BASE 0xe0110000
+
+/* EMEV2 SMU registers */
+#define USIAU0_RSTCTRL 0x094
+#define USIBU1_RSTCTRL 0x0ac
+#define USIBU2_RSTCTRL 0x0b0
+#define USIBU3_RSTCTRL 0x0b4
+#define STI_RSTCTRL 0x124
+#define USIAU0GCLKCTRL 0x4a0
+#define USIBU1GCLKCTRL 0x4b8
+#define USIBU2GCLKCTRL 0x4bc
+#define USIBU3GCLKCTRL 0x04c0
+#define STIGCLKCTRL 0x528
+#define USIAU0SCLKDIV 0x61c
+#define USIB2SCLKDIV 0x65c
+#define USIB3SCLKDIV 0x660
+#define STI_CLKSEL 0x688
+#define SMU_GENERAL_REG0 0x7c0
+
+/* not pretty, but hey */
+static void __iomem *smu_base;
+
+static void emev2_smu_write(unsigned long value, int offs)
+{
+ BUG_ON(!smu_base || (offs >= PAGE_SIZE));
+ iowrite32(value, smu_base + offs);
+}
+
+void emev2_set_boot_vector(unsigned long value)
+{
+ emev2_smu_write(value, SMU_GENERAL_REG0);
+}
+
+static struct clk_mapping smu_mapping = {
+ .phys = EMEV2_SMU_BASE,
+ .len = PAGE_SIZE,
+};
+
+/* Fixed 32 KHz root clock from C32K pin */
+static struct clk c32k_clk = {
+ .rate = 32768,
+ .mapping = &smu_mapping,
+};
+
+/* PLL3 multiplies C32K with 7000 */
+static unsigned long pll3_recalc(struct clk *clk)
+{
+ return clk->parent->rate * 7000;
+}
+
+static struct sh_clk_ops pll3_clk_ops = {
+ .recalc = pll3_recalc,
+};
+
+static struct clk pll3_clk = {
+ .ops = &pll3_clk_ops,
+ .parent = &c32k_clk,
+};
+
+static struct clk *main_clks[] = {
+ &c32k_clk,
+ &pll3_clk,
+};
+
+enum { SCLKDIV_USIAU0, SCLKDIV_USIBU2, SCLKDIV_USIBU1, SCLKDIV_USIBU3,
+ SCLKDIV_NR };
+
+#define SCLKDIV(_reg, _shift) \
+{ \
+ .parent = &pll3_clk, \
+ .enable_reg = IOMEM(EMEV2_SMU_BASE + (_reg)), \
+ .enable_bit = _shift, \
+}
+
+static struct clk sclkdiv_clks[SCLKDIV_NR] = {
+ [SCLKDIV_USIAU0] = SCLKDIV(USIAU0SCLKDIV, 0),
+ [SCLKDIV_USIBU2] = SCLKDIV(USIB2SCLKDIV, 16),
+ [SCLKDIV_USIBU1] = SCLKDIV(USIB2SCLKDIV, 0),
+ [SCLKDIV_USIBU3] = SCLKDIV(USIB3SCLKDIV, 0),
+};
+
+enum { GCLK_USIAU0_SCLK, GCLK_USIBU1_SCLK, GCLK_USIBU2_SCLK, GCLK_USIBU3_SCLK,
+ GCLK_STI_SCLK,
+ GCLK_NR };
+
+#define GCLK_SCLK(_parent, _reg) \
+{ \
+ .parent = _parent, \
+ .enable_reg = IOMEM(EMEV2_SMU_BASE + (_reg)), \
+ .enable_bit = 1, /* SCLK_GCC */ \
+}
+
+static struct clk gclk_clks[GCLK_NR] = {
+ [GCLK_USIAU0_SCLK] = GCLK_SCLK(&sclkdiv_clks[SCLKDIV_USIAU0],
+ USIAU0GCLKCTRL),
+ [GCLK_USIBU1_SCLK] = GCLK_SCLK(&sclkdiv_clks[SCLKDIV_USIBU1],
+ USIBU1GCLKCTRL),
+ [GCLK_USIBU2_SCLK] = GCLK_SCLK(&sclkdiv_clks[SCLKDIV_USIBU2],
+ USIBU2GCLKCTRL),
+ [GCLK_USIBU3_SCLK] = GCLK_SCLK(&sclkdiv_clks[SCLKDIV_USIBU3],
+ USIBU3GCLKCTRL),
+ [GCLK_STI_SCLK] = GCLK_SCLK(&c32k_clk, STIGCLKCTRL),
+};
+
+static int emev2_gclk_enable(struct clk *clk)
+{
+ iowrite32(ioread32(clk->mapped_reg) | (1 << clk->enable_bit),
+ clk->mapped_reg);
+ return 0;
+}
+
+static void emev2_gclk_disable(struct clk *clk)
+{
+ iowrite32(ioread32(clk->mapped_reg) & ~(1 << clk->enable_bit),
+ clk->mapped_reg);
+}
+
+static struct sh_clk_ops emev2_gclk_clk_ops = {
+ .enable = emev2_gclk_enable,
+ .disable = emev2_gclk_disable,
+ .recalc = followparent_recalc,
+};
+
+static int __init emev2_gclk_register(struct clk *clks, int nr)
+{
+ struct clk *clkp;
+ int ret = 0;
+ int k;
+
+ for (k = 0; !ret && (k < nr); k++) {
+ clkp = clks + k;
+ clkp->ops = &emev2_gclk_clk_ops;
+ ret |= clk_register(clkp);
+ }
+
+ return ret;
+}
+
+static unsigned long emev2_sclkdiv_recalc(struct clk *clk)
+{
+ unsigned int sclk_div;
+
+ sclk_div = (ioread32(clk->mapped_reg) >> clk->enable_bit) & 0xff;
+
+ return clk->parent->rate / (sclk_div + 1);
+}
+
+static struct sh_clk_ops emev2_sclkdiv_clk_ops = {
+ .recalc = emev2_sclkdiv_recalc,
+};
+
+static int __init emev2_sclkdiv_register(struct clk *clks, int nr)
+{
+ struct clk *clkp;
+ int ret = 0;
+ int k;
+
+ for (k = 0; !ret && (k < nr); k++) {
+ clkp = clks + k;
+ clkp->ops = &emev2_sclkdiv_clk_ops;
+ ret |= clk_register(clkp);
+ }
+
+ return ret;
+}
+
+static struct clk_lookup lookups[] = {
+ CLKDEV_DEV_ID("serial8250-em.0", &gclk_clks[GCLK_USIAU0_SCLK]),
+ CLKDEV_DEV_ID("e1020000.uart", &gclk_clks[GCLK_USIAU0_SCLK]),
+ CLKDEV_DEV_ID("serial8250-em.1", &gclk_clks[GCLK_USIBU1_SCLK]),
+ CLKDEV_DEV_ID("e1030000.uart", &gclk_clks[GCLK_USIBU1_SCLK]),
+ CLKDEV_DEV_ID("serial8250-em.2", &gclk_clks[GCLK_USIBU2_SCLK]),
+ CLKDEV_DEV_ID("e1040000.uart", &gclk_clks[GCLK_USIBU2_SCLK]),
+ CLKDEV_DEV_ID("serial8250-em.3", &gclk_clks[GCLK_USIBU3_SCLK]),
+ CLKDEV_DEV_ID("e1050000.uart", &gclk_clks[GCLK_USIBU3_SCLK]),
+ CLKDEV_DEV_ID("em_sti.0", &gclk_clks[GCLK_STI_SCLK]),
+ CLKDEV_DEV_ID("e0180000.sti", &gclk_clks[GCLK_STI_SCLK]),
+};
+
+void __init emev2_clock_init(void)
+{
+ int k, ret = 0;
+ static int is_setup;
+
+ /* yuck, this is ugly as hell, but the non-smp case of clocks
+ * code is now designed to rely on ioremap() instead of static
+ * entity maps. in the case of smp we need access to the SMU
+ * register earlier than ioremap() is actually working without
+ * any static maps. to enable SMP in ugly but with dynamic
+ * mappings we have to call emev2_clock_init() from different
+ * places depending on UP and SMP...
+ */
+ if (is_setup++)
+ return;
+
+ smu_base = ioremap(EMEV2_SMU_BASE, PAGE_SIZE);
+ BUG_ON(!smu_base);
+
+ /* setup STI timer to run on 37.768 kHz and deassert reset */
+ emev2_smu_write(0, STI_CLKSEL);
+ emev2_smu_write(1, STI_RSTCTRL);
+
+ /* deassert reset for UART0->UART3 */
+ emev2_smu_write(2, USIAU0_RSTCTRL);
+ emev2_smu_write(2, USIBU1_RSTCTRL);
+ emev2_smu_write(2, USIBU2_RSTCTRL);
+ emev2_smu_write(2, USIBU3_RSTCTRL);
+
+ for (k = 0; !ret && (k < ARRAY_SIZE(main_clks)); k++)
+ ret = clk_register(main_clks[k]);
+
+ if (!ret)
+ ret = emev2_sclkdiv_register(sclkdiv_clks, SCLKDIV_NR);
+
+ if (!ret)
+ ret = emev2_gclk_register(gclk_clks, GCLK_NR);
+
+ clkdev_add_table(lookups, ARRAY_SIZE(lookups));
+
+ if (!ret)
+ shmobile_clk_init();
+ else
+ panic("failed to setup emev2 clocks\n");
+}