linux/arch/arm/mach-omap2/prm44xx.c

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/*
* OMAP4 PRM module functions
*
* Copyright (C) 2011 Texas Instruments, Inc.
* Copyright (C) 2010 Nokia Corporation
* Benoît 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>
OMAP4: PRCM: add OMAP4-specific accessor/mutator functions In some ways, the OMAP4 PRCM register layout is quite different than the OMAP2/3 PRCM register layout. For example, on OMAP2/3, from a register layout point of view, all CM instances were located in the CM subsystem, and all PRM instances were located in the PRM subsystem. OMAP4 changes this. Now, for example, some CM instances, such as WKUP_CM and EMU_CM, are located in the system PRM subsystem. And a "local PRCM" exists for the MPU - this PRCM combines registers that would normally appear in both CM and PRM instances, but uses its own register layout which matches neither the OMAP2/3 PRCM layout nor the OMAP4 PRCM layout. To try to deal with this, introduce some new functions, omap4_cminst* and omap4_prminst*. The former is to be used when writing to a CM instance register (no matter what subsystem or hardware module it exists in), and the latter, similarly, with PRM instance registers. To determine which "PRCM partition" to write to, the functions take a PRCM instance ID argument. Subsequent patches add these partition IDs to the OMAP4 powerdomain and clockdomain definitions. As far as I can see, there's really no good way to handle these types of register access inconsistencies. This patch seemed like the least bad approach. Moving forward, the long-term goal is to remove all direct PRCM register access from the PM code. PRCM register access should go through layers such as the powerdomain and clockdomain code that can hide the details of how to interact with the specific hardware variant. While here, rename cm4xxx.c to cm44xx.c to match the naming convention of the other OMAP4 PRCM files. Thanks to Santosh Shilimkar <santosh.shilimkar@ti.com>, Rajendra Nayak <rnayak@ti.com>, and Benoît Cousson <b-cousson@ti.com> for some comments. Signed-off-by: Paul Walmsley <paul@pwsan.com> Cc: Benoît Cousson <b-cousson@ti.com> Cc: Rajendra Nayak <rnayak@ti.com> Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
2010-12-22 04:05:14 +00:00
#include <linux/io.h>
#include <plat/cpu.h>
#include <plat/irqs.h>
#include <plat/prcm.h>
#include "iomap.h"
#include "common.h"
#include "vp.h"
#include "prm44xx.h"
#include "prm-regbits-44xx.h"
#include "prcm44xx.h"
#include "prminst44xx.h"
static const struct omap_prcm_irq omap4_prcm_irqs[] = {
OMAP_PRCM_IRQ("wkup", 0, 0),
OMAP_PRCM_IRQ("io", 9, 1),
};
static struct omap_prcm_irq_setup omap4_prcm_irq_setup = {
.ack = OMAP4_PRM_IRQSTATUS_MPU_OFFSET,
.mask = OMAP4_PRM_IRQENABLE_MPU_OFFSET,
.nr_regs = 2,
.irqs = omap4_prcm_irqs,
.nr_irqs = ARRAY_SIZE(omap4_prcm_irqs),
.irq = OMAP44XX_IRQ_PRCM,
.read_pending_irqs = &omap44xx_prm_read_pending_irqs,
.ocp_barrier = &omap44xx_prm_ocp_barrier,
.save_and_clear_irqen = &omap44xx_prm_save_and_clear_irqen,
.restore_irqen = &omap44xx_prm_restore_irqen,
};
OMAP4: PRCM: add OMAP4-specific accessor/mutator functions In some ways, the OMAP4 PRCM register layout is quite different than the OMAP2/3 PRCM register layout. For example, on OMAP2/3, from a register layout point of view, all CM instances were located in the CM subsystem, and all PRM instances were located in the PRM subsystem. OMAP4 changes this. Now, for example, some CM instances, such as WKUP_CM and EMU_CM, are located in the system PRM subsystem. And a "local PRCM" exists for the MPU - this PRCM combines registers that would normally appear in both CM and PRM instances, but uses its own register layout which matches neither the OMAP2/3 PRCM layout nor the OMAP4 PRCM layout. To try to deal with this, introduce some new functions, omap4_cminst* and omap4_prminst*. The former is to be used when writing to a CM instance register (no matter what subsystem or hardware module it exists in), and the latter, similarly, with PRM instance registers. To determine which "PRCM partition" to write to, the functions take a PRCM instance ID argument. Subsequent patches add these partition IDs to the OMAP4 powerdomain and clockdomain definitions. As far as I can see, there's really no good way to handle these types of register access inconsistencies. This patch seemed like the least bad approach. Moving forward, the long-term goal is to remove all direct PRCM register access from the PM code. PRCM register access should go through layers such as the powerdomain and clockdomain code that can hide the details of how to interact with the specific hardware variant. While here, rename cm4xxx.c to cm44xx.c to match the naming convention of the other OMAP4 PRCM files. Thanks to Santosh Shilimkar <santosh.shilimkar@ti.com>, Rajendra Nayak <rnayak@ti.com>, and Benoît Cousson <b-cousson@ti.com> for some comments. Signed-off-by: Paul Walmsley <paul@pwsan.com> Cc: Benoît Cousson <b-cousson@ti.com> Cc: Rajendra Nayak <rnayak@ti.com> Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
2010-12-22 04:05:14 +00:00
/* PRM low-level functions */
/* Read a register in a CM/PRM instance in the PRM module */
u32 omap4_prm_read_inst_reg(s16 inst, u16 reg)
{
return __raw_readl(OMAP44XX_PRM_REGADDR(inst, reg));
}
/* Write into a register in a CM/PRM instance in the PRM module */
void omap4_prm_write_inst_reg(u32 val, s16 inst, u16 reg)
{
__raw_writel(val, OMAP44XX_PRM_REGADDR(inst, reg));
}
/* Read-modify-write a register in a PRM module. Caller must lock */
u32 omap4_prm_rmw_inst_reg_bits(u32 mask, u32 bits, s16 inst, s16 reg)
{
u32 v;
v = omap4_prm_read_inst_reg(inst, reg);
v &= ~mask;
v |= bits;
omap4_prm_write_inst_reg(v, inst, reg);
return v;
}
/* PRM VP */
/*
* struct omap4_vp - OMAP4 VP register access description.
* @irqstatus_mpu: offset to IRQSTATUS_MPU register for VP
* @tranxdone_status: VP_TRANXDONE_ST bitmask in PRM_IRQSTATUS_MPU reg
*/
struct omap4_vp {
u32 irqstatus_mpu;
u32 tranxdone_status;
};
static struct omap4_vp omap4_vp[] = {
[OMAP4_VP_VDD_MPU_ID] = {
.irqstatus_mpu = OMAP4_PRM_IRQSTATUS_MPU_2_OFFSET,
.tranxdone_status = OMAP4430_VP_MPU_TRANXDONE_ST_MASK,
},
[OMAP4_VP_VDD_IVA_ID] = {
.irqstatus_mpu = OMAP4_PRM_IRQSTATUS_MPU_OFFSET,
.tranxdone_status = OMAP4430_VP_IVA_TRANXDONE_ST_MASK,
},
[OMAP4_VP_VDD_CORE_ID] = {
.irqstatus_mpu = OMAP4_PRM_IRQSTATUS_MPU_OFFSET,
.tranxdone_status = OMAP4430_VP_CORE_TRANXDONE_ST_MASK,
},
};
u32 omap4_prm_vp_check_txdone(u8 vp_id)
{
struct omap4_vp *vp = &omap4_vp[vp_id];
u32 irqstatus;
irqstatus = omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION,
OMAP4430_PRM_OCP_SOCKET_INST,
vp->irqstatus_mpu);
return irqstatus & vp->tranxdone_status;
}
void omap4_prm_vp_clear_txdone(u8 vp_id)
{
struct omap4_vp *vp = &omap4_vp[vp_id];
omap4_prminst_write_inst_reg(vp->tranxdone_status,
OMAP4430_PRM_PARTITION,
OMAP4430_PRM_OCP_SOCKET_INST,
vp->irqstatus_mpu);
};
u32 omap4_prm_vcvp_read(u8 offset)
{
return omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION,
OMAP4430_PRM_DEVICE_INST, offset);
}
void omap4_prm_vcvp_write(u32 val, u8 offset)
{
omap4_prminst_write_inst_reg(val, OMAP4430_PRM_PARTITION,
OMAP4430_PRM_DEVICE_INST, offset);
}
u32 omap4_prm_vcvp_rmw(u32 mask, u32 bits, u8 offset)
{
return omap4_prminst_rmw_inst_reg_bits(mask, bits,
OMAP4430_PRM_PARTITION,
OMAP4430_PRM_DEVICE_INST,
offset);
}
static inline u32 _read_pending_irq_reg(u16 irqen_offs, u16 irqst_offs)
{
u32 mask, st;
/* XXX read mask from RAM? */
mask = omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
irqen_offs);
st = omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST, irqst_offs);
return mask & st;
}
/**
* omap44xx_prm_read_pending_irqs - read pending PRM MPU IRQs into @events
* @events: ptr to two consecutive u32s, preallocated by caller
*
* Read PRM_IRQSTATUS_MPU* bits, AND'ed with the currently-enabled PRM
* MPU IRQs, and store the result into the two u32s pointed to by @events.
* No return value.
*/
void omap44xx_prm_read_pending_irqs(unsigned long *events)
{
events[0] = _read_pending_irq_reg(OMAP4_PRM_IRQENABLE_MPU_OFFSET,
OMAP4_PRM_IRQSTATUS_MPU_OFFSET);
events[1] = _read_pending_irq_reg(OMAP4_PRM_IRQENABLE_MPU_2_OFFSET,
OMAP4_PRM_IRQSTATUS_MPU_2_OFFSET);
}
/**
* omap44xx_prm_ocp_barrier - force buffered MPU writes to the PRM to complete
*
* Force any buffered writes to the PRM IP block to complete. Needed
* by the PRM IRQ handler, which reads and writes directly to the IP
* block, to avoid race conditions after acknowledging or clearing IRQ
* bits. No return value.
*/
void omap44xx_prm_ocp_barrier(void)
{
omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
OMAP4_REVISION_PRM_OFFSET);
}
/**
* omap44xx_prm_save_and_clear_irqen - save/clear PRM_IRQENABLE_MPU* regs
* @saved_mask: ptr to a u32 array to save IRQENABLE bits
*
* Save the PRM_IRQENABLE_MPU and PRM_IRQENABLE_MPU_2 registers to
* @saved_mask. @saved_mask must be allocated by the caller.
* Intended to be used in the PRM interrupt handler suspend callback.
* The OCP barrier is needed to ensure the write to disable PRM
* interrupts reaches the PRM before returning; otherwise, spurious
* interrupts might occur. No return value.
*/
void omap44xx_prm_save_and_clear_irqen(u32 *saved_mask)
{
saved_mask[0] =
omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
OMAP4_PRM_IRQSTATUS_MPU_OFFSET);
saved_mask[1] =
omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
OMAP4_PRM_IRQSTATUS_MPU_2_OFFSET);
omap4_prm_write_inst_reg(0, OMAP4430_PRM_OCP_SOCKET_INST,
OMAP4_PRM_IRQENABLE_MPU_OFFSET);
omap4_prm_write_inst_reg(0, OMAP4430_PRM_OCP_SOCKET_INST,
OMAP4_PRM_IRQENABLE_MPU_2_OFFSET);
/* OCP barrier */
omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
OMAP4_REVISION_PRM_OFFSET);
}
/**
* omap44xx_prm_restore_irqen - set PRM_IRQENABLE_MPU* registers from args
* @saved_mask: ptr to a u32 array of IRQENABLE bits saved previously
*
* Restore the PRM_IRQENABLE_MPU and PRM_IRQENABLE_MPU_2 registers from
* @saved_mask. Intended to be used in the PRM interrupt handler resume
* callback to restore values saved by omap44xx_prm_save_and_clear_irqen().
* No OCP barrier should be needed here; any pending PRM interrupts will fire
* once the writes reach the PRM. No return value.
*/
void omap44xx_prm_restore_irqen(u32 *saved_mask)
{
omap4_prm_write_inst_reg(saved_mask[0], OMAP4430_PRM_OCP_SOCKET_INST,
OMAP4_PRM_IRQENABLE_MPU_OFFSET);
omap4_prm_write_inst_reg(saved_mask[1], OMAP4430_PRM_OCP_SOCKET_INST,
OMAP4_PRM_IRQENABLE_MPU_2_OFFSET);
}
static int __init omap4xxx_prcm_init(void)
{
if (cpu_is_omap44xx())
return omap_prcm_register_chain_handler(&omap4_prcm_irq_setup);
return 0;
}
subsys_initcall(omap4xxx_prcm_init);