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Diffstat (limited to 'arch/arm/mach-omap2/clkt34xx_dpll3m2.c')
-rw-r--r--arch/arm/mach-omap2/clkt34xx_dpll3m2.c121
1 files changed, 121 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/clkt34xx_dpll3m2.c b/arch/arm/mach-omap2/clkt34xx_dpll3m2.c
new file mode 100644
index 000000000000..b2b1e37bb6bb
--- /dev/null
+++ b/arch/arm/mach-omap2/clkt34xx_dpll3m2.c
@@ -0,0 +1,121 @@
+/*
+ * OMAP34xx M2 divider clock code
+ *
+ * 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 <plat/clock.h>
+#include <plat/sram.h>
+#include <plat/sdrc.h>
+
+#include "clock.h"
+#include "clock3xxx.h"
+#include "clock34xx.h"
+#include "sdrc.h"
+
+#define CYCLES_PER_MHZ 1000000
+
+/*
+ * CORE DPLL (DPLL3) M2 divider rate programming functions
+ *
+ * These call into SRAM code to do the actual CM writes, since the SDRAM
+ * is clocked from DPLL3.
+ */
+
+/**
+ * omap3_core_dpll_m2_set_rate - set CORE DPLL M2 divider
+ * @clk: struct clk * of DPLL to set
+ * @rate: rounded target rate
+ *
+ * Program the DPLL M2 divider with the rounded target rate. Returns
+ * -EINVAL upon error, or 0 upon success.
+ */
+int omap3_core_dpll_m2_set_rate(struct clk *clk, unsigned long rate)
+{
+ u32 new_div = 0;
+ u32 unlock_dll = 0;
+ u32 c;
+ unsigned long validrate, sdrcrate, _mpurate;
+ struct omap_sdrc_params *sdrc_cs0;
+ struct omap_sdrc_params *sdrc_cs1;
+ int ret;
+
+ if (!clk || !rate)
+ return -EINVAL;
+
+ validrate = omap2_clksel_round_rate_div(clk, rate, &new_div);
+ if (validrate != rate)
+ return -EINVAL;
+
+ sdrcrate = sdrc_ick_p->rate;
+ if (rate > clk->rate)
+ sdrcrate <<= ((rate / clk->rate) >> 1);
+ else
+ sdrcrate >>= ((clk->rate / rate) >> 1);
+
+ ret = omap2_sdrc_get_params(sdrcrate, &sdrc_cs0, &sdrc_cs1);
+ if (ret)
+ return -EINVAL;
+
+ if (sdrcrate < MIN_SDRC_DLL_LOCK_FREQ) {
+ pr_debug("clock: will unlock SDRC DLL\n");
+ unlock_dll = 1;
+ }
+
+ /*
+ * XXX This only needs to be done when the CPU frequency changes
+ */
+ _mpurate = arm_fck_p->rate / CYCLES_PER_MHZ;
+ c = (_mpurate << SDRC_MPURATE_SCALE) >> SDRC_MPURATE_BASE_SHIFT;
+ c += 1; /* for safety */
+ c *= SDRC_MPURATE_LOOPS;
+ c >>= SDRC_MPURATE_SCALE;
+ if (c == 0)
+ c = 1;
+
+ pr_debug("clock: changing CORE DPLL rate from %lu to %lu\n", clk->rate,
+ validrate);
+ pr_debug("clock: SDRC CS0 timing params used:"
+ " RFR %08x CTRLA %08x CTRLB %08x MR %08x\n",
+ sdrc_cs0->rfr_ctrl, sdrc_cs0->actim_ctrla,
+ sdrc_cs0->actim_ctrlb, sdrc_cs0->mr);
+ if (sdrc_cs1)
+ pr_debug("clock: SDRC CS1 timing params used: "
+ " RFR %08x CTRLA %08x CTRLB %08x MR %08x\n",
+ sdrc_cs1->rfr_ctrl, sdrc_cs1->actim_ctrla,
+ sdrc_cs1->actim_ctrlb, sdrc_cs1->mr);
+
+ if (sdrc_cs1)
+ omap3_configure_core_dpll(
+ new_div, unlock_dll, c, rate > clk->rate,
+ sdrc_cs0->rfr_ctrl, sdrc_cs0->actim_ctrla,
+ sdrc_cs0->actim_ctrlb, sdrc_cs0->mr,
+ sdrc_cs1->rfr_ctrl, sdrc_cs1->actim_ctrla,
+ sdrc_cs1->actim_ctrlb, sdrc_cs1->mr);
+ else
+ omap3_configure_core_dpll(
+ new_div, unlock_dll, c, rate > clk->rate,
+ sdrc_cs0->rfr_ctrl, sdrc_cs0->actim_ctrla,
+ sdrc_cs0->actim_ctrlb, sdrc_cs0->mr,
+ 0, 0, 0, 0);
+
+ return 0;
+}
+