diff options
Diffstat (limited to 'kernel/arch/arm/mach-omap2/clock3517.c')
| -rw-r--r-- | kernel/arch/arm/mach-omap2/clock3517.c | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/kernel/arch/arm/mach-omap2/clock3517.c b/kernel/arch/arm/mach-omap2/clock3517.c new file mode 100644 index 000000000..4d79ae2c0 --- /dev/null +++ b/kernel/arch/arm/mach-omap2/clock3517.c @@ -0,0 +1,118 @@ +/* + * OMAP3517/3505-specific clock framework functions + * + * Copyright (C) 2010 Texas Instruments, Inc. + * Copyright (C) 2011 Nokia Corporation + * + * Ranjith Lohithakshan + * Paul Walmsley + * + * Parts of this code are based on code written by + * Richard Woodruff, Tony Lindgren, Tuukka Tikkanen, Karthik Dasu, + * Russell King + * + * 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 "clock.h" +#include "clock3517.h" +#include "cm3xxx.h" +#include "cm-regbits-34xx.h" + +/* + * In AM35xx IPSS, the {ICK,FCK} enable bits for modules are exported + * in the same register at a bit offset of 0x8. The EN_ACK for ICK is + * at an offset of 4 from ICK enable bit. + */ +#define AM35XX_IPSS_ICK_MASK 0xF +#define AM35XX_IPSS_ICK_EN_ACK_OFFSET 0x4 +#define AM35XX_IPSS_ICK_FCK_OFFSET 0x8 +#define AM35XX_IPSS_CLK_IDLEST_VAL 0 + +/** + * am35xx_clk_find_idlest - return clock ACK info for AM35XX IPSS + * @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 + * + * The interface clocks on AM35xx IPSS reflects the clock idle status + * in the enable register itsel at a bit offset of 4 from the enable + * bit. A value of 1 indicates that clock is enabled. + */ +static void am35xx_clk_find_idlest(struct clk_hw_omap *clk, + void __iomem **idlest_reg, + u8 *idlest_bit, + u8 *idlest_val) +{ + *idlest_reg = (__force void __iomem *)(clk->enable_reg); + *idlest_bit = clk->enable_bit + AM35XX_IPSS_ICK_EN_ACK_OFFSET; + *idlest_val = AM35XX_IPSS_CLK_IDLEST_VAL; +} + +/** + * am35xx_clk_find_companion - find companion clock to @clk + * @clk: struct clk * to find the companion clock of + * @other_reg: void __iomem ** to return the companion clock CM_*CLKEN va in + * @other_bit: u8 ** to return the companion clock bit shift in + * + * Some clocks don't have companion clocks. For example, modules with + * only an interface clock (such as HECC) don't have a companion + * clock. Right now, this code relies on the hardware exporting a bit + * in the correct companion register that indicates that the + * nonexistent 'companion clock' is active. Future patches will + * associate this type of code with per-module data structures to + * avoid this issue, and remove the casts. No return value. + */ +static void am35xx_clk_find_companion(struct clk_hw_omap *clk, + void __iomem **other_reg, + u8 *other_bit) +{ + *other_reg = (__force void __iomem *)(clk->enable_reg); + if (clk->enable_bit & AM35XX_IPSS_ICK_MASK) + *other_bit = clk->enable_bit + AM35XX_IPSS_ICK_FCK_OFFSET; + else + *other_bit = clk->enable_bit - AM35XX_IPSS_ICK_FCK_OFFSET; +} +const struct clk_hw_omap_ops clkhwops_am35xx_ipss_module_wait = { + .find_idlest = am35xx_clk_find_idlest, + .find_companion = am35xx_clk_find_companion, +}; + +/** + * am35xx_clk_ipss_find_idlest - return CM_IDLEST info for IPSS + * @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 + * + * The IPSS target CM_IDLEST bit is at a different shift from the + * CM_{I,F}CLKEN bit. Pass back the correct info via @idlest_reg + * and @idlest_bit. No return value. + */ +static void am35xx_clk_ipss_find_idlest(struct clk_hw_omap *clk, + void __iomem **idlest_reg, + u8 *idlest_bit, + u8 *idlest_val) +{ + u32 r; + + r = (((__force u32)clk->enable_reg & ~0xf0) | 0x20); + *idlest_reg = (__force void __iomem *)r; + *idlest_bit = AM35XX_ST_IPSS_SHIFT; + *idlest_val = OMAP34XX_CM_IDLEST_VAL; +} + +const struct clk_hw_omap_ops clkhwops_am35xx_ipss_wait = { + .allow_idle = omap2_clkt_iclk_allow_idle, + .deny_idle = omap2_clkt_iclk_deny_idle, + .find_idlest = am35xx_clk_ipss_find_idlest, + .find_companion = omap2_clk_dflt_find_companion, +}; |