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author | Linus Torvalds <torvalds@linux-foundation.org> | 2010-10-25 13:46:56 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-10-25 13:46:56 -0700 |
commit | 7b6181e06841f5ad15c4ff708b967b4db65a64de (patch) | |
tree | bdfcf5b74b692f76581156e452d268b64c795200 /arch/arm/mach-omap2/prm44xx.c | |
parent | 72e58063d63c5f0a7bf65312f1e3a5ed9bb5c2ff (diff) | |
parent | bc487fb341af05120bccb9f59ce76302391dcc77 (diff) | |
download | op-kernel-dev-7b6181e06841f5ad15c4ff708b967b4db65a64de.zip op-kernel-dev-7b6181e06841f5ad15c4ff708b967b4db65a64de.tar.gz |
Merge branch 'omap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6
* 'omap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6: (163 commits)
omap: complete removal of machine_desc.io_pg_offst and .phys_io
omap: UART: fix wakeup registers for OMAP24xx UART2
omap: Fix spotty MMC voltages
ASoC: OMAP4: MCPDM: Remove unnecessary include of plat/control.h
serial: omap-serial: fix signess error
OMAP3: DMA: Errata i541: sDMA FIFO draining does not finish
omap: dma: Fix buffering disable bit setting for omap24xx
omap: serial: Fix the boot-up crash/reboot without CONFIG_PM
OMAP3: PM: fix scratchpad memory accesses for off-mode
omap4: pandaboard: enable the ehci port on pandaboard
omap4: pandaboard: Fix the init if CONFIG_MMC_OMAP_HS is not set
omap4: pandaboard: remove unused hsmmc definition
OMAP: McBSP: Remove null omap44xx ops comment
OMAP: McBSP: Swap CLKS source definition
OMAP: McBSP: Fix CLKR and FSR signal muxing
OMAP2+: clock: reduce the amount of standard debugging while disabling unused clocks
OMAP: control: move plat-omap/control.h to mach-omap2/control.h
OMAP: split plat-omap/common.c
OMAP: McBSP: implement functional clock switching via clock framework
OMAP: McBSP: implement McBSP CLKR and FSR signal muxing via mach-omap2/mcbsp.c
...
Fixed up trivial conflicts in arch/arm/mach-omap2/
{board-zoom-peripherals.c,devices.c} as per Tony
Diffstat (limited to 'arch/arm/mach-omap2/prm44xx.c')
-rw-r--r-- | arch/arm/mach-omap2/prm44xx.c | 116 |
1 files changed, 116 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/prm44xx.c b/arch/arm/mach-omap2/prm44xx.c new file mode 100644 index 0000000..a1ff918 --- /dev/null +++ b/arch/arm/mach-omap2/prm44xx.c @@ -0,0 +1,116 @@ +/* + * OMAP4 PRM module functions + * + * Copyright (C) 2010 Texas Instruments, Inc. + * Copyright (C) 2010 Nokia Corporation + * BenoƮt Cousson + * Paul Walmsley + * + * 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. + */ + +#include <linux/kernel.h> +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/err.h> + +#include <plat/common.h> +#include <plat/cpu.h> +#include <plat/prcm.h> + +#include "prm.h" +#include "prm-regbits-44xx.h" + +/* + * Address offset (in bytes) between the reset control and the reset + * status registers: 4 bytes on OMAP4 + */ +#define OMAP4_RST_CTRL_ST_OFFSET 4 + +/** + * omap4_prm_is_hardreset_asserted - read the HW reset line state of + * submodules contained in the hwmod module + * @rstctrl_reg: RM_RSTCTRL register address for this module + * @shift: register bit shift corresponding to the reset line to check + * + * Returns 1 if the (sub)module hardreset line is currently asserted, + * 0 if the (sub)module hardreset line is not currently asserted, or + * -EINVAL upon parameter error. + */ +int omap4_prm_is_hardreset_asserted(void __iomem *rstctrl_reg, u8 shift) +{ + if (!cpu_is_omap44xx() || !rstctrl_reg) + return -EINVAL; + + return omap4_prm_read_bits_shift(rstctrl_reg, (1 << shift)); +} + +/** + * omap4_prm_assert_hardreset - assert the HW reset line of a submodule + * @rstctrl_reg: RM_RSTCTRL register address for this module + * @shift: register bit shift corresponding to the reset line to assert + * + * Some IPs like dsp, ipu or iva contain processors that require an HW + * reset line to be asserted / deasserted in order to fully enable the + * IP. These modules may have multiple hard-reset lines that reset + * different 'submodules' inside the IP block. This function will + * place the submodule into reset. Returns 0 upon success or -EINVAL + * upon an argument error. + */ +int omap4_prm_assert_hardreset(void __iomem *rstctrl_reg, u8 shift) +{ + u32 mask; + + if (!cpu_is_omap44xx() || !rstctrl_reg) + return -EINVAL; + + mask = 1 << shift; + omap4_prm_rmw_reg_bits(mask, mask, rstctrl_reg); + + return 0; +} + +/** + * omap4_prm_deassert_hardreset - deassert a submodule hardreset line and wait + * @rstctrl_reg: RM_RSTCTRL register address for this module + * @shift: register bit shift corresponding to the reset line to deassert + * + * Some IPs like dsp, ipu or iva contain processors that require an HW + * reset line to be asserted / deasserted in order to fully enable the + * IP. These modules may have multiple hard-reset lines that reset + * different 'submodules' inside the IP block. This function will + * take the submodule out of reset and wait until the PRCM indicates + * that the reset has completed before returning. Returns 0 upon success or + * -EINVAL upon an argument error, -EEXIST if the submodule was already out + * of reset, or -EBUSY if the submodule did not exit reset promptly. + */ +int omap4_prm_deassert_hardreset(void __iomem *rstctrl_reg, u8 shift) +{ + u32 mask; + void __iomem *rstst_reg; + int c; + + if (!cpu_is_omap44xx() || !rstctrl_reg) + return -EINVAL; + + rstst_reg = rstctrl_reg + OMAP4_RST_CTRL_ST_OFFSET; + + mask = 1 << shift; + + /* Check the current status to avoid de-asserting the line twice */ + if (omap4_prm_read_bits_shift(rstctrl_reg, mask) == 0) + return -EEXIST; + + /* Clear the reset status by writing 1 to the status bit */ + omap4_prm_rmw_reg_bits(0xffffffff, mask, rstst_reg); + /* de-assert the reset control line */ + omap4_prm_rmw_reg_bits(mask, 0, rstctrl_reg); + /* wait the status to be set */ + omap_test_timeout(omap4_prm_read_bits_shift(rstst_reg, mask), + MAX_MODULE_HARDRESET_WAIT, c); + + return (c == MAX_MODULE_HARDRESET_WAIT) ? -EBUSY : 0; +} + |