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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/arm/mach-omap2/clock3xxx.c
Initial import
Diffstat (limited to 'arch/arm/mach-omap2/clock3xxx.c')
-rw-r--r--arch/arm/mach-omap2/clock3xxx.c135
1 files changed, 135 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/clock3xxx.c b/arch/arm/mach-omap2/clock3xxx.c
new file mode 100644
index 000000000..a9e86db5d
--- /dev/null
+++ b/arch/arm/mach-omap2/clock3xxx.c
@@ -0,0 +1,135 @@
+/*
+ * OMAP3-specific clock framework functions
+ *
+ * Copyright (C) 2007-2008 Texas Instruments, Inc.
+ * Copyright (C) 2007-2010 Nokia Corporation
+ *
+ * Paul Walmsley
+ * Jouni Högander
+ *
+ * Parts of this code are based on code written by
+ * Richard Woodruff, Tony Lindgren, Tuukka Tikkanen, Karthik Dasu
+ *
+ * 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.
+ */
+#undef DEBUG
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+
+#include "soc.h"
+#include "clock.h"
+#include "clock3xxx.h"
+#include "prm2xxx_3xxx.h"
+#include "prm-regbits-34xx.h"
+#include "cm2xxx_3xxx.h"
+#include "cm-regbits-34xx.h"
+
+/*
+ * DPLL5_FREQ_FOR_USBHOST: USBHOST and USBTLL are the only clocks
+ * that are sourced by DPLL5, and both of these require this clock
+ * to be at 120 MHz for proper operation.
+ */
+#define DPLL5_FREQ_FOR_USBHOST 120000000
+
+/* needed by omap3_core_dpll_m2_set_rate() */
+struct clk *sdrc_ick_p, *arm_fck_p;
+
+/**
+ * omap3_dpll4_set_rate - set rate for omap3 per-dpll
+ * @hw: clock to change
+ * @rate: target rate for clock
+ * @parent_rate: rate of the parent clock
+ *
+ * Check if the current SoC supports the per-dpll reprogram operation
+ * or not, and then do the rate change if supported. Returns -EINVAL
+ * if not supported, 0 for success, and potential error codes from the
+ * clock rate change.
+ */
+int omap3_dpll4_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ /*
+ * According to the 12-5 CDP code from TI, "Limitation 2.5"
+ * on 3430ES1 prevents us from changing DPLL multipliers or dividers
+ * on DPLL4.
+ */
+ if (ti_clk_features.flags & TI_CLK_DPLL4_DENY_REPROGRAM) {
+ pr_err("clock: DPLL4 cannot change rate due to silicon 'Limitation 2.5' on 3430ES1.\n");
+ return -EINVAL;
+ }
+
+ return omap3_noncore_dpll_set_rate(hw, rate, parent_rate);
+}
+
+/**
+ * omap3_dpll4_set_rate_and_parent - set rate and parent for omap3 per-dpll
+ * @hw: clock to change
+ * @rate: target rate for clock
+ * @parent_rate: rate of the parent clock
+ * @index: parent index, 0 - reference clock, 1 - bypass clock
+ *
+ * Check if the current SoC support the per-dpll reprogram operation
+ * or not, and then do the rate + parent change if supported. Returns
+ * -EINVAL if not supported, 0 for success, and potential error codes
+ * from the clock rate change.
+ */
+int omap3_dpll4_set_rate_and_parent(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate, u8 index)
+{
+ if (ti_clk_features.flags & TI_CLK_DPLL4_DENY_REPROGRAM) {
+ pr_err("clock: DPLL4 cannot change rate due to silicon 'Limitation 2.5' on 3430ES1.\n");
+ return -EINVAL;
+ }
+
+ return omap3_noncore_dpll_set_rate_and_parent(hw, rate, parent_rate,
+ index);
+}
+
+void __init omap3_clk_lock_dpll5(void)
+{
+ struct clk *dpll5_clk;
+ struct clk *dpll5_m2_clk;
+
+ dpll5_clk = clk_get(NULL, "dpll5_ck");
+ clk_set_rate(dpll5_clk, DPLL5_FREQ_FOR_USBHOST);
+ clk_prepare_enable(dpll5_clk);
+
+ /* Program dpll5_m2_clk divider for no division */
+ dpll5_m2_clk = clk_get(NULL, "dpll5_m2_ck");
+ clk_prepare_enable(dpll5_m2_clk);
+ clk_set_rate(dpll5_m2_clk, DPLL5_FREQ_FOR_USBHOST);
+
+ clk_disable_unprepare(dpll5_m2_clk);
+ clk_disable_unprepare(dpll5_clk);
+ return;
+}
+
+/* Common clock code */
+
+/*
+ * Switch the MPU rate if specified on cmdline. We cannot do this
+ * early until cmdline is parsed. XXX This should be removed from the
+ * clock code and handled by the OPP layer code in the near future.
+ */
+static int __init omap3xxx_clk_arch_init(void)
+{
+ int ret;
+
+ if (!cpu_is_omap34xx())
+ return 0;
+
+ ret = omap2_clk_switch_mpurate_at_boot("dpll1_ck");
+ if (!ret)
+ omap2_clk_print_new_rates("osc_sys_ck", "core_ck", "arm_fck");
+
+ return ret;
+}
+
+omap_arch_initcall(omap3xxx_clk_arch_init);
+
+