swh:1:snp:32555a3fd8878f019c2ebd6c964bc1edcaeff337
Tip revision: bcf876870b95592b52519ed4aafcf9d95999bc9c authored by Linus Torvalds on 02 August 2020, 21:21:45 UTC
Linux 5.8
Linux 5.8
Tip revision: bcf8768
omap4-common.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* OMAP4 specific common source file.
*
* Copyright (C) 2010 Texas Instruments, Inc.
* Author:
* Santosh Shilimkar <santosh.shilimkar@ti.com>
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/irqchip.h>
#include <linux/platform_device.h>
#include <linux/memblock.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/export.h>
#include <linux/irqchip/arm-gic.h>
#include <linux/of_address.h>
#include <linux/reboot.h>
#include <linux/genalloc.h>
#include <asm/hardware/cache-l2x0.h>
#include <asm/mach/map.h>
#include <asm/memblock.h>
#include <asm/smp_twd.h>
#include "omap-wakeupgen.h"
#include "soc.h"
#include "iomap.h"
#include "common.h"
#include "prminst44xx.h"
#include "prcm_mpu44xx.h"
#include "omap4-sar-layout.h"
#include "omap-secure.h"
#include "sram.h"
#ifdef CONFIG_CACHE_L2X0
static void __iomem *l2cache_base;
#endif
static void __iomem *sar_ram_base;
static void __iomem *gic_dist_base_addr;
static void __iomem *twd_base;
#define IRQ_LOCALTIMER 29
#ifdef CONFIG_OMAP_INTERCONNECT_BARRIER
/* Used to implement memory barrier on DRAM path */
#define OMAP4_DRAM_BARRIER_VA 0xfe600000
static void __iomem *dram_sync, *sram_sync;
static phys_addr_t dram_sync_paddr;
static u32 dram_sync_size;
/*
* The OMAP4 bus structure contains asynchronous bridges which can buffer
* data writes from the MPU. These asynchronous bridges can be found on
* paths between the MPU to EMIF, and the MPU to L3 interconnects.
*
* We need to be careful about re-ordering which can happen as a result
* of different accesses being performed via different paths, and
* therefore different asynchronous bridges.
*/
/*
* OMAP4 interconnect barrier which is called for each mb() and wmb().
* This is to ensure that normal paths to DRAM (normal memory, cacheable
* accesses) are properly synchronised with writes to DMA coherent memory
* (normal memory, uncacheable) and device writes.
*
* The mb() and wmb() barriers only operate only on the MPU->MA->EMIF
* path, as we need to ensure that data is visible to other system
* masters prior to writes to those system masters being seen.
*
* Note: the SRAM path is not synchronised via mb() and wmb().
*/
static void omap4_mb(void)
{
if (dram_sync)
writel_relaxed(0, dram_sync);
}
/*
* OMAP4 Errata i688 - asynchronous bridge corruption when entering WFI.
*
* If a data is stalled inside asynchronous bridge because of back
* pressure, it may be accepted multiple times, creating pointer
* misalignment that will corrupt next transfers on that data path until
* next reset of the system. No recovery procedure once the issue is hit,
* the path remains consistently broken.
*
* Async bridges can be found on paths between MPU to EMIF and MPU to L3
* interconnects.
*
* This situation can happen only when the idle is initiated by a Master
* Request Disconnection (which is trigged by software when executing WFI
* on the CPU).
*
* The work-around for this errata needs all the initiators connected
* through an async bridge to ensure that data path is properly drained
* before issuing WFI. This condition will be met if one Strongly ordered
* access is performed to the target right before executing the WFI.
*
* In MPU case, L3 T2ASYNC FIFO and DDR T2ASYNC FIFO needs to be drained.
* IO barrier ensure that there is no synchronisation loss on initiators
* operating on both interconnect port simultaneously.
*
* This is a stronger version of the OMAP4 memory barrier below, and
* operates on both the MPU->MA->EMIF path but also the MPU->OCP path
* as well, and is necessary prior to executing a WFI.
*/
void omap_interconnect_sync(void)
{
if (dram_sync && sram_sync) {
writel_relaxed(readl_relaxed(dram_sync), dram_sync);
writel_relaxed(readl_relaxed(sram_sync), sram_sync);
isb();
}
}
static int __init omap4_sram_init(void)
{
struct device_node *np;
struct gen_pool *sram_pool;
if (!soc_is_omap44xx() && !soc_is_omap54xx())
return 0;
np = of_find_compatible_node(NULL, NULL, "ti,omap4-mpu");
if (!np)
pr_warn("%s:Unable to allocate sram needed to handle errata I688\n",
__func__);
sram_pool = of_gen_pool_get(np, "sram", 0);
if (!sram_pool)
pr_warn("%s:Unable to get sram pool needed to handle errata I688\n",
__func__);
else
sram_sync = (void *)gen_pool_alloc(sram_pool, PAGE_SIZE);
return 0;
}
omap_arch_initcall(omap4_sram_init);
/* Steal one page physical memory for barrier implementation */
void __init omap_barrier_reserve_memblock(void)
{
dram_sync_size = ALIGN(PAGE_SIZE, SZ_1M);
dram_sync_paddr = arm_memblock_steal(dram_sync_size, SZ_1M);
}
void __init omap_barriers_init(void)
{
struct map_desc dram_io_desc[1];
dram_io_desc[0].virtual = OMAP4_DRAM_BARRIER_VA;
dram_io_desc[0].pfn = __phys_to_pfn(dram_sync_paddr);
dram_io_desc[0].length = dram_sync_size;
dram_io_desc[0].type = MT_MEMORY_RW_SO;
iotable_init(dram_io_desc, ARRAY_SIZE(dram_io_desc));
dram_sync = (void __iomem *) dram_io_desc[0].virtual;
pr_info("OMAP4: Map %pa to %p for dram barrier\n",
&dram_sync_paddr, dram_sync);
soc_mb = omap4_mb;
}
#endif
void gic_dist_disable(void)
{
if (gic_dist_base_addr)
writel_relaxed(0x0, gic_dist_base_addr + GIC_DIST_CTRL);
}
void gic_dist_enable(void)
{
if (gic_dist_base_addr)
writel_relaxed(0x1, gic_dist_base_addr + GIC_DIST_CTRL);
}
bool gic_dist_disabled(void)
{
return !(readl_relaxed(gic_dist_base_addr + GIC_DIST_CTRL) & 0x1);
}
void gic_timer_retrigger(void)
{
u32 twd_int = readl_relaxed(twd_base + TWD_TIMER_INTSTAT);
u32 gic_int = readl_relaxed(gic_dist_base_addr + GIC_DIST_PENDING_SET);
u32 twd_ctrl = readl_relaxed(twd_base + TWD_TIMER_CONTROL);
if (twd_int && !(gic_int & BIT(IRQ_LOCALTIMER))) {
/*
* The local timer interrupt got lost while the distributor was
* disabled. Ack the pending interrupt, and retrigger it.
*/
pr_warn("%s: lost localtimer interrupt\n", __func__);
writel_relaxed(1, twd_base + TWD_TIMER_INTSTAT);
if (!(twd_ctrl & TWD_TIMER_CONTROL_PERIODIC)) {
writel_relaxed(1, twd_base + TWD_TIMER_COUNTER);
twd_ctrl |= TWD_TIMER_CONTROL_ENABLE;
writel_relaxed(twd_ctrl, twd_base + TWD_TIMER_CONTROL);
}
}
}
#ifdef CONFIG_CACHE_L2X0
void __iomem *omap4_get_l2cache_base(void)
{
return l2cache_base;
}
void omap4_l2c310_write_sec(unsigned long val, unsigned reg)
{
unsigned smc_op;
switch (reg) {
case L2X0_CTRL:
smc_op = OMAP4_MON_L2X0_CTRL_INDEX;
break;
case L2X0_AUX_CTRL:
smc_op = OMAP4_MON_L2X0_AUXCTRL_INDEX;
break;
case L2X0_DEBUG_CTRL:
smc_op = OMAP4_MON_L2X0_DBG_CTRL_INDEX;
break;
case L310_PREFETCH_CTRL:
smc_op = OMAP4_MON_L2X0_PREFETCH_INDEX;
break;
case L310_POWER_CTRL:
pr_info_once("OMAP L2C310: ROM does not support power control setting\n");
return;
default:
WARN_ONCE(1, "OMAP L2C310: ignoring write to reg 0x%x\n", reg);
return;
}
omap_smc1(smc_op, val);
}
int __init omap_l2_cache_init(void)
{
/* Static mapping, never released */
l2cache_base = ioremap(OMAP44XX_L2CACHE_BASE, SZ_4K);
if (WARN_ON(!l2cache_base))
return -ENOMEM;
return 0;
}
#endif
void __iomem *omap4_get_sar_ram_base(void)
{
return sar_ram_base;
}
/*
* SAR RAM used to save and restore the HW context in low power modes.
* Note that we need to initialize this very early for kexec. See
* omap4_mpuss_early_init().
*/
void __init omap4_sar_ram_init(void)
{
unsigned long sar_base;
/*
* To avoid code running on other OMAPs in
* multi-omap builds
*/
if (cpu_is_omap44xx())
sar_base = OMAP44XX_SAR_RAM_BASE;
else if (soc_is_omap54xx())
sar_base = OMAP54XX_SAR_RAM_BASE;
else
return;
/* Static mapping, never released */
sar_ram_base = ioremap(sar_base, SZ_16K);
if (WARN_ON(!sar_ram_base))
return;
}
static const struct of_device_id intc_match[] = {
{ .compatible = "ti,omap4-wugen-mpu", },
{ .compatible = "ti,omap5-wugen-mpu", },
{ },
};
static struct device_node *intc_node;
void __init omap_gic_of_init(void)
{
struct device_node *np;
intc_node = of_find_matching_node(NULL, intc_match);
if (WARN_ON(!intc_node)) {
pr_err("No WUGEN found in DT, system will misbehave.\n");
pr_err("UPDATE YOUR DEVICE TREE!\n");
}
/* Extract GIC distributor and TWD bases for OMAP4460 ROM Errata WA */
if (!cpu_is_omap446x())
goto skip_errata_init;
np = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-gic");
gic_dist_base_addr = of_iomap(np, 0);
WARN_ON(!gic_dist_base_addr);
np = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-twd-timer");
twd_base = of_iomap(np, 0);
WARN_ON(!twd_base);
skip_errata_init:
irqchip_init();
}