linux/arch/arm/mach-davinci/psc.c
Mark A. Greer fe277d9bbb davinci: PSC: Clear bits in MDCTL reg before setting new bits
Clear any set bits in the 'NEXT' field of the MDCTL register in the
Power and Sleep Controller (PSC) before setting any new bits.
This also allows some minor cleanup by removing some no longer
needed lines of code.

Signed-off-by: Mark A. Greer <mgreer@mvista.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
2009-04-27 09:49:43 -07:00

100 lines
2.8 KiB
C

/*
* TI DaVinci Power and Sleep Controller (PSC)
*
* Copyright (C) 2006 Texas Instruments.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/io.h>
#include <mach/cputype.h>
#include <mach/hardware.h>
#include <mach/psc.h>
#include <mach/mux.h>
#define DAVINCI_PWR_SLEEP_CNTRL_BASE 0x01C41000
/* PSC register offsets */
#define EPCPR 0x070
#define PTCMD 0x120
#define PTSTAT 0x128
#define PDSTAT 0x200
#define PDCTL1 0x304
#define MDSTAT 0x800
#define MDCTL 0xA00
#define MDSTAT_STATE_MASK 0x1f
/* Return nonzero iff the domain's clock is active */
int __init davinci_psc_is_clk_active(unsigned int id)
{
void __iomem *psc_base = IO_ADDRESS(DAVINCI_PWR_SLEEP_CNTRL_BASE);
u32 mdstat = __raw_readl(psc_base + MDSTAT + 4 * id);
/* if clocked, state can be "Enable" or "SyncReset" */
return mdstat & BIT(12);
}
/* Enable or disable a PSC domain */
void davinci_psc_config(unsigned int domain, unsigned int id, char enable)
{
u32 epcpr, ptcmd, ptstat, pdstat, pdctl1, mdstat, mdctl;
void __iomem *psc_base = IO_ADDRESS(DAVINCI_PWR_SLEEP_CNTRL_BASE);
u32 next_state = enable ? 0x3 : 0x2; /* 0x3 enables, 0x2 disables */
mdctl = __raw_readl(psc_base + MDCTL + 4 * id);
mdctl &= ~MDSTAT_STATE_MASK;
mdctl |= next_state;
__raw_writel(mdctl, psc_base + MDCTL + 4 * id);
pdstat = __raw_readl(psc_base + PDSTAT);
if ((pdstat & 0x00000001) == 0) {
pdctl1 = __raw_readl(psc_base + PDCTL1);
pdctl1 |= 0x1;
__raw_writel(pdctl1, psc_base + PDCTL1);
ptcmd = 1 << domain;
__raw_writel(ptcmd, psc_base + PTCMD);
do {
epcpr = __raw_readl(psc_base + EPCPR);
} while ((((epcpr >> domain) & 1) == 0));
pdctl1 = __raw_readl(psc_base + PDCTL1);
pdctl1 |= 0x100;
__raw_writel(pdctl1, psc_base + PDCTL1);
do {
ptstat = __raw_readl(psc_base +
PTSTAT);
} while (!(((ptstat >> domain) & 1) == 0));
} else {
ptcmd = 1 << domain;
__raw_writel(ptcmd, psc_base + PTCMD);
do {
ptstat = __raw_readl(psc_base + PTSTAT);
} while (!(((ptstat >> domain) & 1) == 0));
}
do {
mdstat = __raw_readl(psc_base + MDSTAT + 4 * id);
} while (!((mdstat & MDSTAT_STATE_MASK) == next_state));
}