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linux-next/arch/arm/mach-omap2/clock2430.c
Paul Walmsley 81b34fbecb OMAP2 clock: split OMAP2420, OMAP2430 clock data into their own files
In preparation for multi-OMAP2 kernels, split
mach-omap2/clock2xxx_data.c into mach-omap2/clock2420_data.c and
mach-omap2/clock2430_data.c.  2430 uses a different device space
physical memory layout than past or future OMAPs, and we use a
different virtual memory layout as well, which causes trouble for
architecture-level code/data that tries to support both.  We tried
using offsets from the virtual base last year, but those patches never
made it upstream; so after some discussion with Tony about the best
all-around approach, we'll just grit our teeth and duplicate the
structures.  The maintenance advantages of a single kernel config that
can compile and boot on OMAP2, 3, and 4 platforms are simply too
compelling.

This approach does have some nice benefits beyond multi-OMAP 2 kernel
support.  The runtime size of OMAP2420-specific and OMAP2430-specific
kernels is smaller, since unused clocks for the other OMAP2 chip will
no longer be compiled in.  (At some point we will mark the clock data
__initdata and allocate it during registration, which will eliminate
the runtime memory advantage.)  It also makes the clock trees slightly
easier to read, since 2420-specific and 2430-specific clocks are no
longer mixed together.

This patch also splits 2430-specific clock code into its own file,
mach-omap2/clock2430.c, which is only compiled in for 2430 builds -
mostly for organizational clarity.

While here, fix a bug in the OMAP2430 clock tree: "emul_ck" was
incorrectly marked as being 2420-only, when actually it is present on
both OMAP2420 and OMAP2430.

Thanks to Tony for some good discussions about how to approach this
problem.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Richard Woodruff <r-woodruff2@ti.com>
2010-02-24 12:29:42 -07:00

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1.8 KiB
C

/*
* clock2430.c - OMAP2430-specific clock integration code
*
* Copyright (C) 2005-2008 Texas Instruments, Inc.
* Copyright (C) 2004-2010 Nokia Corporation
*
* Contacts:
* Richard Woodruff <r-woodruff2@ti.com>
* Paul Walmsley
*
* Based on earlier work by Tuukka Tikkanen, Tony Lindgren,
* Gordon McNutt and RidgeRun, Inc.
*
* 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/clk.h>
#include <linux/io.h>
#include <plat/clock.h>
#include "clock.h"
#include "clock2xxx.h"
#include "cm.h"
#include "cm-regbits-24xx.h"
/**
* omap2430_clk_i2chs_find_idlest - return CM_IDLEST info for 2430 I2CHS
* @clk: struct clk * being enabled
* @idlest_reg: void __iomem ** to store CM_IDLEST reg address into
* @idlest_bit: pointer to a u8 to store the CM_IDLEST bit shift into
* @idlest_val: pointer to a u8 to store the CM_IDLEST indicator
*
* OMAP2430 I2CHS CM_IDLEST bits are in CM_IDLEST1_CORE, but the
* CM_*CLKEN bits are in CM_{I,F}CLKEN2_CORE. This custom function
* passes back the correct CM_IDLEST register address for I2CHS
* modules. No return value.
*/
static void omap2430_clk_i2chs_find_idlest(struct clk *clk,
void __iomem **idlest_reg,
u8 *idlest_bit,
u8 *idlest_val)
{
*idlest_reg = OMAP2430_CM_REGADDR(CORE_MOD, CM_IDLEST);
*idlest_bit = clk->enable_bit;
*idlest_val = OMAP24XX_CM_IDLEST_VAL;
}
/* 2430 I2CHS has non-standard IDLEST register */
const struct clkops clkops_omap2430_i2chs_wait = {
.enable = omap2_dflt_clk_enable,
.disable = omap2_dflt_clk_disable,
.find_idlest = omap2430_clk_i2chs_find_idlest,
.find_companion = omap2_clk_dflt_find_companion,
};