https://github.com/torvalds/linux
Tip revision: b7bfaa761d760e72a969d116517eaa12e404c262 authored by Linus Torvalds on 08 January 2023, 17:49:43 UTC
Linux 6.2-rc3
Linux 6.2-rc3
Tip revision: b7bfaa7
emif.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* EMIF driver
*
* Copyright (C) 2012 Texas Instruments, Inc.
*
* Aneesh V <aneesh@ti.com>
* Santosh Shilimkar <santosh.shilimkar@ti.com>
*/
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/reboot.h>
#include <linux/platform_data/emif_plat.h>
#include <linux/io.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#include <linux/module.h>
#include <linux/list.h>
#include <linux/spinlock.h>
#include <linux/pm.h>
#include "emif.h"
#include "jedec_ddr.h"
#include "of_memory.h"
/**
* struct emif_data - Per device static data for driver's use
* @duplicate: Whether the DDR devices attached to this EMIF
* instance are exactly same as that on EMIF1. In
* this case we can save some memory and processing
* @temperature_level: Maximum temperature of LPDDR2 devices attached
* to this EMIF - read from MR4 register. If there
* are two devices attached to this EMIF, this
* value is the maximum of the two temperature
* levels.
* @node: node in the device list
* @base: base address of memory-mapped IO registers.
* @dev: device pointer.
* @regs_cache: An array of 'struct emif_regs' that stores
* calculated register values for different
* frequencies, to avoid re-calculating them on
* each DVFS transition.
* @curr_regs: The set of register values used in the last
* frequency change (i.e. corresponding to the
* frequency in effect at the moment)
* @plat_data: Pointer to saved platform data.
* @debugfs_root: dentry to the root folder for EMIF in debugfs
* @np_ddr: Pointer to ddr device tree node
*/
struct emif_data {
u8 duplicate;
u8 temperature_level;
u8 lpmode;
struct list_head node;
unsigned long irq_state;
void __iomem *base;
struct device *dev;
struct emif_regs *regs_cache[EMIF_MAX_NUM_FREQUENCIES];
struct emif_regs *curr_regs;
struct emif_platform_data *plat_data;
struct dentry *debugfs_root;
struct device_node *np_ddr;
};
static struct emif_data *emif1;
static DEFINE_SPINLOCK(emif_lock);
static unsigned long irq_state;
static LIST_HEAD(device_list);
#ifdef CONFIG_DEBUG_FS
static void do_emif_regdump_show(struct seq_file *s, struct emif_data *emif,
struct emif_regs *regs)
{
u32 type = emif->plat_data->device_info->type;
u32 ip_rev = emif->plat_data->ip_rev;
seq_printf(s, "EMIF register cache dump for %dMHz\n",
regs->freq/1000000);
seq_printf(s, "ref_ctrl_shdw\t: 0x%08x\n", regs->ref_ctrl_shdw);
seq_printf(s, "sdram_tim1_shdw\t: 0x%08x\n", regs->sdram_tim1_shdw);
seq_printf(s, "sdram_tim2_shdw\t: 0x%08x\n", regs->sdram_tim2_shdw);
seq_printf(s, "sdram_tim3_shdw\t: 0x%08x\n", regs->sdram_tim3_shdw);
if (ip_rev == EMIF_4D) {
seq_printf(s, "read_idle_ctrl_shdw_normal\t: 0x%08x\n",
regs->read_idle_ctrl_shdw_normal);
seq_printf(s, "read_idle_ctrl_shdw_volt_ramp\t: 0x%08x\n",
regs->read_idle_ctrl_shdw_volt_ramp);
} else if (ip_rev == EMIF_4D5) {
seq_printf(s, "dll_calib_ctrl_shdw_normal\t: 0x%08x\n",
regs->dll_calib_ctrl_shdw_normal);
seq_printf(s, "dll_calib_ctrl_shdw_volt_ramp\t: 0x%08x\n",
regs->dll_calib_ctrl_shdw_volt_ramp);
}
if (type == DDR_TYPE_LPDDR2_S2 || type == DDR_TYPE_LPDDR2_S4) {
seq_printf(s, "ref_ctrl_shdw_derated\t: 0x%08x\n",
regs->ref_ctrl_shdw_derated);
seq_printf(s, "sdram_tim1_shdw_derated\t: 0x%08x\n",
regs->sdram_tim1_shdw_derated);
seq_printf(s, "sdram_tim3_shdw_derated\t: 0x%08x\n",
regs->sdram_tim3_shdw_derated);
}
}
static int emif_regdump_show(struct seq_file *s, void *unused)
{
struct emif_data *emif = s->private;
struct emif_regs **regs_cache;
int i;
if (emif->duplicate)
regs_cache = emif1->regs_cache;
else
regs_cache = emif->regs_cache;
for (i = 0; i < EMIF_MAX_NUM_FREQUENCIES && regs_cache[i]; i++) {
do_emif_regdump_show(s, emif, regs_cache[i]);
seq_putc(s, '\n');
}
return 0;
}
DEFINE_SHOW_ATTRIBUTE(emif_regdump);
static int emif_mr4_show(struct seq_file *s, void *unused)
{
struct emif_data *emif = s->private;
seq_printf(s, "MR4=%d\n", emif->temperature_level);
return 0;
}
DEFINE_SHOW_ATTRIBUTE(emif_mr4);
static int __init_or_module emif_debugfs_init(struct emif_data *emif)
{
emif->debugfs_root = debugfs_create_dir(dev_name(emif->dev), NULL);
debugfs_create_file("regcache_dump", S_IRUGO, emif->debugfs_root, emif,
&emif_regdump_fops);
debugfs_create_file("mr4", S_IRUGO, emif->debugfs_root, emif,
&emif_mr4_fops);
return 0;
}
static void __exit emif_debugfs_exit(struct emif_data *emif)
{
debugfs_remove_recursive(emif->debugfs_root);
emif->debugfs_root = NULL;
}
#else
static inline int __init_or_module emif_debugfs_init(struct emif_data *emif)
{
return 0;
}
static inline void __exit emif_debugfs_exit(struct emif_data *emif)
{
}
#endif
/*
* Get bus width used by EMIF. Note that this may be different from the
* bus width of the DDR devices used. For instance two 16-bit DDR devices
* may be connected to a given CS of EMIF. In this case bus width as far
* as EMIF is concerned is 32, where as the DDR bus width is 16 bits.
*/
static u32 get_emif_bus_width(struct emif_data *emif)
{
u32 width;
void __iomem *base = emif->base;
width = (readl(base + EMIF_SDRAM_CONFIG) & NARROW_MODE_MASK)
>> NARROW_MODE_SHIFT;
width = width == 0 ? 32 : 16;
return width;
}
static void set_lpmode(struct emif_data *emif, u8 lpmode)
{
u32 temp;
void __iomem *base = emif->base;
/*
* Workaround for errata i743 - LPDDR2 Power-Down State is Not
* Efficient
*
* i743 DESCRIPTION:
* The EMIF supports power-down state for low power. The EMIF
* automatically puts the SDRAM into power-down after the memory is
* not accessed for a defined number of cycles and the
* EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE bit field is set to 0x4.
* As the EMIF supports automatic output impedance calibration, a ZQ
* calibration long command is issued every time it exits active
* power-down and precharge power-down modes. The EMIF waits and
* blocks any other command during this calibration.
* The EMIF does not allow selective disabling of ZQ calibration upon
* exit of power-down mode. Due to very short periods of power-down
* cycles, ZQ calibration overhead creates bandwidth issues and
* increases overall system power consumption. On the other hand,
* issuing ZQ calibration long commands when exiting self-refresh is
* still required.
*
* WORKAROUND
* Because there is no power consumption benefit of the power-down due
* to the calibration and there is a performance risk, the guideline
* is to not allow power-down state and, therefore, to not have set
* the EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE bit field to 0x4.
*/
if ((emif->plat_data->ip_rev == EMIF_4D) &&
(lpmode == EMIF_LP_MODE_PWR_DN)) {
WARN_ONCE(1,
"REG_LP_MODE = LP_MODE_PWR_DN(4) is prohibited by erratum i743 switch to LP_MODE_SELF_REFRESH(2)\n");
/* rollback LP_MODE to Self-refresh mode */
lpmode = EMIF_LP_MODE_SELF_REFRESH;
}
temp = readl(base + EMIF_POWER_MANAGEMENT_CONTROL);
temp &= ~LP_MODE_MASK;
temp |= (lpmode << LP_MODE_SHIFT);
writel(temp, base + EMIF_POWER_MANAGEMENT_CONTROL);
}
static void do_freq_update(void)
{
struct emif_data *emif;
/*
* Workaround for errata i728: Disable LPMODE during FREQ_UPDATE
*
* i728 DESCRIPTION:
* The EMIF automatically puts the SDRAM into self-refresh mode
* after the EMIF has not performed accesses during
* EMIF_PWR_MGMT_CTRL[7:4] REG_SR_TIM number of DDR clock cycles
* and the EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE bit field is set
* to 0x2. If during a small window the following three events
* occur:
* - The SR_TIMING counter expires
* - And frequency change is requested
* - And OCP access is requested
* Then it causes instable clock on the DDR interface.
*
* WORKAROUND
* To avoid the occurrence of the three events, the workaround
* is to disable the self-refresh when requesting a frequency
* change. Before requesting a frequency change the software must
* program EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE to 0x0. When the
* frequency change has been done, the software can reprogram
* EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE to 0x2
*/
list_for_each_entry(emif, &device_list, node) {
if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
set_lpmode(emif, EMIF_LP_MODE_DISABLE);
}
/*
* TODO: Do FREQ_UPDATE here when an API
* is available for this as part of the new
* clock framework
*/
list_for_each_entry(emif, &device_list, node) {
if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
set_lpmode(emif, EMIF_LP_MODE_SELF_REFRESH);
}
}
/* Find addressing table entry based on the device's type and density */
static const struct lpddr2_addressing *get_addressing_table(
const struct ddr_device_info *device_info)
{
u32 index, type, density;
type = device_info->type;
density = device_info->density;
switch (type) {
case DDR_TYPE_LPDDR2_S4:
index = density - 1;
break;
case DDR_TYPE_LPDDR2_S2:
switch (density) {
case DDR_DENSITY_1Gb:
case DDR_DENSITY_2Gb:
index = density + 3;
break;
default:
index = density - 1;
}
break;
default:
return NULL;
}
return &lpddr2_jedec_addressing_table[index];
}
static u32 get_zq_config_reg(const struct lpddr2_addressing *addressing,
bool cs1_used, bool cal_resistors_per_cs)
{
u32 zq = 0, val = 0;
val = EMIF_ZQCS_INTERVAL_US * 1000 / addressing->tREFI_ns;
zq |= val << ZQ_REFINTERVAL_SHIFT;
val = DIV_ROUND_UP(T_ZQCL_DEFAULT_NS, T_ZQCS_DEFAULT_NS) - 1;
zq |= val << ZQ_ZQCL_MULT_SHIFT;
val = DIV_ROUND_UP(T_ZQINIT_DEFAULT_NS, T_ZQCL_DEFAULT_NS) - 1;
zq |= val << ZQ_ZQINIT_MULT_SHIFT;
zq |= ZQ_SFEXITEN_ENABLE << ZQ_SFEXITEN_SHIFT;
if (cal_resistors_per_cs)
zq |= ZQ_DUALCALEN_ENABLE << ZQ_DUALCALEN_SHIFT;
else
zq |= ZQ_DUALCALEN_DISABLE << ZQ_DUALCALEN_SHIFT;
zq |= ZQ_CS0EN_MASK; /* CS0 is used for sure */
val = cs1_used ? 1 : 0;
zq |= val << ZQ_CS1EN_SHIFT;
return zq;
}
static u32 get_temp_alert_config(const struct lpddr2_addressing *addressing,
const struct emif_custom_configs *custom_configs, bool cs1_used,
u32 sdram_io_width, u32 emif_bus_width)
{
u32 alert = 0, interval, devcnt;
if (custom_configs && (custom_configs->mask &
EMIF_CUSTOM_CONFIG_TEMP_ALERT_POLL_INTERVAL))
interval = custom_configs->temp_alert_poll_interval_ms;
else
interval = TEMP_ALERT_POLL_INTERVAL_DEFAULT_MS;
interval *= 1000000; /* Convert to ns */
interval /= addressing->tREFI_ns; /* Convert to refresh cycles */
alert |= (interval << TA_REFINTERVAL_SHIFT);
/*
* sdram_io_width is in 'log2(x) - 1' form. Convert emif_bus_width
* also to this form and subtract to get TA_DEVCNT, which is
* in log2(x) form.
*/
emif_bus_width = __fls(emif_bus_width) - 1;
devcnt = emif_bus_width - sdram_io_width;
alert |= devcnt << TA_DEVCNT_SHIFT;
/* DEVWDT is in 'log2(x) - 3' form */
alert |= (sdram_io_width - 2) << TA_DEVWDT_SHIFT;
alert |= 1 << TA_SFEXITEN_SHIFT;
alert |= 1 << TA_CS0EN_SHIFT;
alert |= (cs1_used ? 1 : 0) << TA_CS1EN_SHIFT;
return alert;
}
static u32 get_pwr_mgmt_ctrl(u32 freq, struct emif_data *emif, u32 ip_rev)
{
u32 pwr_mgmt_ctrl = 0, timeout;
u32 lpmode = EMIF_LP_MODE_SELF_REFRESH;
u32 timeout_perf = EMIF_LP_MODE_TIMEOUT_PERFORMANCE;
u32 timeout_pwr = EMIF_LP_MODE_TIMEOUT_POWER;
u32 freq_threshold = EMIF_LP_MODE_FREQ_THRESHOLD;
u32 mask;
u8 shift;
struct emif_custom_configs *cust_cfgs = emif->plat_data->custom_configs;
if (cust_cfgs && (cust_cfgs->mask & EMIF_CUSTOM_CONFIG_LPMODE)) {
lpmode = cust_cfgs->lpmode;
timeout_perf = cust_cfgs->lpmode_timeout_performance;
timeout_pwr = cust_cfgs->lpmode_timeout_power;
freq_threshold = cust_cfgs->lpmode_freq_threshold;
}
/* Timeout based on DDR frequency */
timeout = freq >= freq_threshold ? timeout_perf : timeout_pwr;
/*
* The value to be set in register is "log2(timeout) - 3"
* if timeout < 16 load 0 in register
* if timeout is not a power of 2, round to next highest power of 2
*/
if (timeout < 16) {
timeout = 0;
} else {
if (timeout & (timeout - 1))
timeout <<= 1;
timeout = __fls(timeout) - 3;
}
switch (lpmode) {
case EMIF_LP_MODE_CLOCK_STOP:
shift = CS_TIM_SHIFT;
mask = CS_TIM_MASK;
break;
case EMIF_LP_MODE_SELF_REFRESH:
/* Workaround for errata i735 */
if (timeout < 6)
timeout = 6;
shift = SR_TIM_SHIFT;
mask = SR_TIM_MASK;
break;
case EMIF_LP_MODE_PWR_DN:
shift = PD_TIM_SHIFT;
mask = PD_TIM_MASK;
break;
case EMIF_LP_MODE_DISABLE:
default:
mask = 0;
shift = 0;
break;
}
/* Round to maximum in case of overflow, BUT warn! */
if (lpmode != EMIF_LP_MODE_DISABLE && timeout > mask >> shift) {
pr_err("TIMEOUT Overflow - lpmode=%d perf=%d pwr=%d freq=%d\n",
lpmode,
timeout_perf,
timeout_pwr,
freq_threshold);
WARN(1, "timeout=0x%02x greater than 0x%02x. Using max\n",
timeout, mask >> shift);
timeout = mask >> shift;
}
/* Setup required timing */
pwr_mgmt_ctrl = (timeout << shift) & mask;
/* setup a default mask for rest of the modes */
pwr_mgmt_ctrl |= (SR_TIM_MASK | CS_TIM_MASK | PD_TIM_MASK) &
~mask;
/* No CS_TIM in EMIF_4D5 */
if (ip_rev == EMIF_4D5)
pwr_mgmt_ctrl &= ~CS_TIM_MASK;
pwr_mgmt_ctrl |= lpmode << LP_MODE_SHIFT;
return pwr_mgmt_ctrl;
}
/*
* Get the temperature level of the EMIF instance:
* Reads the MR4 register of attached SDRAM parts to find out the temperature
* level. If there are two parts attached(one on each CS), then the temperature
* level for the EMIF instance is the higher of the two temperatures.
*/
static void get_temperature_level(struct emif_data *emif)
{
u32 temp, temperature_level;
void __iomem *base;
base = emif->base;
/* Read mode register 4 */
writel(DDR_MR4, base + EMIF_LPDDR2_MODE_REG_CONFIG);
temperature_level = readl(base + EMIF_LPDDR2_MODE_REG_DATA);
temperature_level = (temperature_level & MR4_SDRAM_REF_RATE_MASK) >>
MR4_SDRAM_REF_RATE_SHIFT;
if (emif->plat_data->device_info->cs1_used) {
writel(DDR_MR4 | CS_MASK, base + EMIF_LPDDR2_MODE_REG_CONFIG);
temp = readl(base + EMIF_LPDDR2_MODE_REG_DATA);
temp = (temp & MR4_SDRAM_REF_RATE_MASK)
>> MR4_SDRAM_REF_RATE_SHIFT;
temperature_level = max(temp, temperature_level);
}
/* treat everything less than nominal(3) in MR4 as nominal */
if (unlikely(temperature_level < SDRAM_TEMP_NOMINAL))
temperature_level = SDRAM_TEMP_NOMINAL;
/* if we get reserved value in MR4 persist with the existing value */
if (likely(temperature_level != SDRAM_TEMP_RESERVED_4))
emif->temperature_level = temperature_level;
}
/*
* setup_temperature_sensitive_regs() - set the timings for temperature
* sensitive registers. This happens once at initialisation time based
* on the temperature at boot time and subsequently based on the temperature
* alert interrupt. Temperature alert can happen when the temperature
* increases or drops. So this function can have the effect of either
* derating the timings or going back to nominal values.
*/
static void setup_temperature_sensitive_regs(struct emif_data *emif,
struct emif_regs *regs)
{
u32 tim1, tim3, ref_ctrl, type;
void __iomem *base = emif->base;
u32 temperature;
type = emif->plat_data->device_info->type;
tim1 = regs->sdram_tim1_shdw;
tim3 = regs->sdram_tim3_shdw;
ref_ctrl = regs->ref_ctrl_shdw;
/* No de-rating for non-lpddr2 devices */
if (type != DDR_TYPE_LPDDR2_S2 && type != DDR_TYPE_LPDDR2_S4)
goto out;
temperature = emif->temperature_level;
if (temperature == SDRAM_TEMP_HIGH_DERATE_REFRESH) {
ref_ctrl = regs->ref_ctrl_shdw_derated;
} else if (temperature == SDRAM_TEMP_HIGH_DERATE_REFRESH_AND_TIMINGS) {
tim1 = regs->sdram_tim1_shdw_derated;
tim3 = regs->sdram_tim3_shdw_derated;
ref_ctrl = regs->ref_ctrl_shdw_derated;
}
out:
writel(tim1, base + EMIF_SDRAM_TIMING_1_SHDW);
writel(tim3, base + EMIF_SDRAM_TIMING_3_SHDW);
writel(ref_ctrl, base + EMIF_SDRAM_REFRESH_CTRL_SHDW);
}
static irqreturn_t handle_temp_alert(void __iomem *base, struct emif_data *emif)
{
u32 old_temp_level;
irqreturn_t ret = IRQ_HANDLED;
struct emif_custom_configs *custom_configs;
spin_lock_irqsave(&emif_lock, irq_state);
old_temp_level = emif->temperature_level;
get_temperature_level(emif);
if (unlikely(emif->temperature_level == old_temp_level)) {
goto out;
} else if (!emif->curr_regs) {
dev_err(emif->dev, "temperature alert before registers are calculated, not de-rating timings\n");
goto out;
}
custom_configs = emif->plat_data->custom_configs;
/*
* IF we detect higher than "nominal rating" from DDR sensor
* on an unsupported DDR part, shutdown system
*/
if (custom_configs && !(custom_configs->mask &
EMIF_CUSTOM_CONFIG_EXTENDED_TEMP_PART)) {
if (emif->temperature_level >= SDRAM_TEMP_HIGH_DERATE_REFRESH) {
dev_err(emif->dev,
"%s:NOT Extended temperature capable memory. Converting MR4=0x%02x as shutdown event\n",
__func__, emif->temperature_level);
/*
* Temperature far too high - do kernel_power_off()
* from thread context
*/
emif->temperature_level = SDRAM_TEMP_VERY_HIGH_SHUTDOWN;
ret = IRQ_WAKE_THREAD;
goto out;
}
}
if (emif->temperature_level < old_temp_level ||
emif->temperature_level == SDRAM_TEMP_VERY_HIGH_SHUTDOWN) {
/*
* Temperature coming down - defer handling to thread OR
* Temperature far too high - do kernel_power_off() from
* thread context
*/
ret = IRQ_WAKE_THREAD;
} else {
/* Temperature is going up - handle immediately */
setup_temperature_sensitive_regs(emif, emif->curr_regs);
do_freq_update();
}
out:
spin_unlock_irqrestore(&emif_lock, irq_state);
return ret;
}
static irqreturn_t emif_interrupt_handler(int irq, void *dev_id)
{
u32 interrupts;
struct emif_data *emif = dev_id;
void __iomem *base = emif->base;
struct device *dev = emif->dev;
irqreturn_t ret = IRQ_HANDLED;
/* Save the status and clear it */
interrupts = readl(base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS);
writel(interrupts, base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS);
/*
* Handle temperature alert
* Temperature alert should be same for all ports
* So, it's enough to process it only for one of the ports
*/
if (interrupts & TA_SYS_MASK)
ret = handle_temp_alert(base, emif);
if (interrupts & ERR_SYS_MASK)
dev_err(dev, "Access error from SYS port - %x\n", interrupts);
if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE) {
/* Save the status and clear it */
interrupts = readl(base + EMIF_LL_OCP_INTERRUPT_STATUS);
writel(interrupts, base + EMIF_LL_OCP_INTERRUPT_STATUS);
if (interrupts & ERR_LL_MASK)
dev_err(dev, "Access error from LL port - %x\n",
interrupts);
}
return ret;
}
static irqreturn_t emif_threaded_isr(int irq, void *dev_id)
{
struct emif_data *emif = dev_id;
if (emif->temperature_level == SDRAM_TEMP_VERY_HIGH_SHUTDOWN) {
dev_emerg(emif->dev, "SDRAM temperature exceeds operating limit.. Needs shut down!!!\n");
/* If we have Power OFF ability, use it, else try restarting */
if (kernel_can_power_off()) {
kernel_power_off();
} else {
WARN(1, "FIXME: NO pm_power_off!!! trying restart\n");
kernel_restart("SDRAM Over-temp Emergency restart");
}
return IRQ_HANDLED;
}
spin_lock_irqsave(&emif_lock, irq_state);
if (emif->curr_regs) {
setup_temperature_sensitive_regs(emif, emif->curr_regs);
do_freq_update();
} else {
dev_err(emif->dev, "temperature alert before registers are calculated, not de-rating timings\n");
}
spin_unlock_irqrestore(&emif_lock, irq_state);
return IRQ_HANDLED;
}
static void clear_all_interrupts(struct emif_data *emif)
{
void __iomem *base = emif->base;
writel(readl(base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS),
base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS);
if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE)
writel(readl(base + EMIF_LL_OCP_INTERRUPT_STATUS),
base + EMIF_LL_OCP_INTERRUPT_STATUS);
}
static void disable_and_clear_all_interrupts(struct emif_data *emif)
{
void __iomem *base = emif->base;
/* Disable all interrupts */
writel(readl(base + EMIF_SYSTEM_OCP_INTERRUPT_ENABLE_SET),
base + EMIF_SYSTEM_OCP_INTERRUPT_ENABLE_CLEAR);
if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE)
writel(readl(base + EMIF_LL_OCP_INTERRUPT_ENABLE_SET),
base + EMIF_LL_OCP_INTERRUPT_ENABLE_CLEAR);
/* Clear all interrupts */
clear_all_interrupts(emif);
}
static int __init_or_module setup_interrupts(struct emif_data *emif, u32 irq)
{
u32 interrupts, type;
void __iomem *base = emif->base;
type = emif->plat_data->device_info->type;
clear_all_interrupts(emif);
/* Enable interrupts for SYS interface */
interrupts = EN_ERR_SYS_MASK;
if (type == DDR_TYPE_LPDDR2_S2 || type == DDR_TYPE_LPDDR2_S4)
interrupts |= EN_TA_SYS_MASK;
writel(interrupts, base + EMIF_SYSTEM_OCP_INTERRUPT_ENABLE_SET);
/* Enable interrupts for LL interface */
if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE) {
/* TA need not be enabled for LL */
interrupts = EN_ERR_LL_MASK;
writel(interrupts, base + EMIF_LL_OCP_INTERRUPT_ENABLE_SET);
}
/* setup IRQ handlers */
return devm_request_threaded_irq(emif->dev, irq,
emif_interrupt_handler,
emif_threaded_isr,
0, dev_name(emif->dev),
emif);
}
static void __init_or_module emif_onetime_settings(struct emif_data *emif)
{
u32 pwr_mgmt_ctrl, zq, temp_alert_cfg;
void __iomem *base = emif->base;
const struct lpddr2_addressing *addressing;
const struct ddr_device_info *device_info;
device_info = emif->plat_data->device_info;
addressing = get_addressing_table(device_info);
/*
* Init power management settings
* We don't know the frequency yet. Use a high frequency
* value for a conservative timeout setting
*/
pwr_mgmt_ctrl = get_pwr_mgmt_ctrl(1000000000, emif,
emif->plat_data->ip_rev);
emif->lpmode = (pwr_mgmt_ctrl & LP_MODE_MASK) >> LP_MODE_SHIFT;
writel(pwr_mgmt_ctrl, base + EMIF_POWER_MANAGEMENT_CONTROL);
/* Init ZQ calibration settings */
zq = get_zq_config_reg(addressing, device_info->cs1_used,
device_info->cal_resistors_per_cs);
writel(zq, base + EMIF_SDRAM_OUTPUT_IMPEDANCE_CALIBRATION_CONFIG);
/* Check temperature level temperature level*/
get_temperature_level(emif);
if (emif->temperature_level == SDRAM_TEMP_VERY_HIGH_SHUTDOWN)
dev_emerg(emif->dev, "SDRAM temperature exceeds operating limit.. Needs shut down!!!\n");
/* Init temperature polling */
temp_alert_cfg = get_temp_alert_config(addressing,
emif->plat_data->custom_configs, device_info->cs1_used,
device_info->io_width, get_emif_bus_width(emif));
writel(temp_alert_cfg, base + EMIF_TEMPERATURE_ALERT_CONFIG);
/*
* Program external PHY control registers that are not frequency
* dependent
*/
if (emif->plat_data->phy_type != EMIF_PHY_TYPE_INTELLIPHY)
return;
writel(EMIF_EXT_PHY_CTRL_1_VAL, base + EMIF_EXT_PHY_CTRL_1_SHDW);
writel(EMIF_EXT_PHY_CTRL_5_VAL, base + EMIF_EXT_PHY_CTRL_5_SHDW);
writel(EMIF_EXT_PHY_CTRL_6_VAL, base + EMIF_EXT_PHY_CTRL_6_SHDW);
writel(EMIF_EXT_PHY_CTRL_7_VAL, base + EMIF_EXT_PHY_CTRL_7_SHDW);
writel(EMIF_EXT_PHY_CTRL_8_VAL, base + EMIF_EXT_PHY_CTRL_8_SHDW);
writel(EMIF_EXT_PHY_CTRL_9_VAL, base + EMIF_EXT_PHY_CTRL_9_SHDW);
writel(EMIF_EXT_PHY_CTRL_10_VAL, base + EMIF_EXT_PHY_CTRL_10_SHDW);
writel(EMIF_EXT_PHY_CTRL_11_VAL, base + EMIF_EXT_PHY_CTRL_11_SHDW);
writel(EMIF_EXT_PHY_CTRL_12_VAL, base + EMIF_EXT_PHY_CTRL_12_SHDW);
writel(EMIF_EXT_PHY_CTRL_13_VAL, base + EMIF_EXT_PHY_CTRL_13_SHDW);
writel(EMIF_EXT_PHY_CTRL_14_VAL, base + EMIF_EXT_PHY_CTRL_14_SHDW);
writel(EMIF_EXT_PHY_CTRL_15_VAL, base + EMIF_EXT_PHY_CTRL_15_SHDW);
writel(EMIF_EXT_PHY_CTRL_16_VAL, base + EMIF_EXT_PHY_CTRL_16_SHDW);
writel(EMIF_EXT_PHY_CTRL_17_VAL, base + EMIF_EXT_PHY_CTRL_17_SHDW);
writel(EMIF_EXT_PHY_CTRL_18_VAL, base + EMIF_EXT_PHY_CTRL_18_SHDW);
writel(EMIF_EXT_PHY_CTRL_19_VAL, base + EMIF_EXT_PHY_CTRL_19_SHDW);
writel(EMIF_EXT_PHY_CTRL_20_VAL, base + EMIF_EXT_PHY_CTRL_20_SHDW);
writel(EMIF_EXT_PHY_CTRL_21_VAL, base + EMIF_EXT_PHY_CTRL_21_SHDW);
writel(EMIF_EXT_PHY_CTRL_22_VAL, base + EMIF_EXT_PHY_CTRL_22_SHDW);
writel(EMIF_EXT_PHY_CTRL_23_VAL, base + EMIF_EXT_PHY_CTRL_23_SHDW);
writel(EMIF_EXT_PHY_CTRL_24_VAL, base + EMIF_EXT_PHY_CTRL_24_SHDW);
}
static void get_default_timings(struct emif_data *emif)
{
struct emif_platform_data *pd = emif->plat_data;
pd->timings = lpddr2_jedec_timings;
pd->timings_arr_size = ARRAY_SIZE(lpddr2_jedec_timings);
dev_warn(emif->dev, "%s: using default timings\n", __func__);
}
static int is_dev_data_valid(u32 type, u32 density, u32 io_width, u32 phy_type,
u32 ip_rev, struct device *dev)
{
int valid;
valid = (type == DDR_TYPE_LPDDR2_S4 ||
type == DDR_TYPE_LPDDR2_S2)
&& (density >= DDR_DENSITY_64Mb
&& density <= DDR_DENSITY_8Gb)
&& (io_width >= DDR_IO_WIDTH_8
&& io_width <= DDR_IO_WIDTH_32);
/* Combinations of EMIF and PHY revisions that we support today */
switch (ip_rev) {
case EMIF_4D:
valid = valid && (phy_type == EMIF_PHY_TYPE_ATTILAPHY);
break;
case EMIF_4D5:
valid = valid && (phy_type == EMIF_PHY_TYPE_INTELLIPHY);
break;
default:
valid = 0;
}
if (!valid)
dev_err(dev, "%s: invalid DDR details\n", __func__);
return valid;
}
static int is_custom_config_valid(struct emif_custom_configs *cust_cfgs,
struct device *dev)
{
int valid = 1;
if ((cust_cfgs->mask & EMIF_CUSTOM_CONFIG_LPMODE) &&
(cust_cfgs->lpmode != EMIF_LP_MODE_DISABLE))
valid = cust_cfgs->lpmode_freq_threshold &&
cust_cfgs->lpmode_timeout_performance &&
cust_cfgs->lpmode_timeout_power;
if (cust_cfgs->mask & EMIF_CUSTOM_CONFIG_TEMP_ALERT_POLL_INTERVAL)
valid = valid && cust_cfgs->temp_alert_poll_interval_ms;
if (!valid)
dev_warn(dev, "%s: invalid custom configs\n", __func__);
return valid;
}
#if defined(CONFIG_OF)
static void __init_or_module of_get_custom_configs(struct device_node *np_emif,
struct emif_data *emif)
{
struct emif_custom_configs *cust_cfgs = NULL;
int len;
const __be32 *lpmode, *poll_intvl;
lpmode = of_get_property(np_emif, "low-power-mode", &len);
poll_intvl = of_get_property(np_emif, "temp-alert-poll-interval", &len);
if (lpmode || poll_intvl)
cust_cfgs = devm_kzalloc(emif->dev, sizeof(*cust_cfgs),
GFP_KERNEL);
if (!cust_cfgs)
return;
if (lpmode) {
cust_cfgs->mask |= EMIF_CUSTOM_CONFIG_LPMODE;
cust_cfgs->lpmode = be32_to_cpup(lpmode);
of_property_read_u32(np_emif,
"low-power-mode-timeout-performance",
&cust_cfgs->lpmode_timeout_performance);
of_property_read_u32(np_emif,
"low-power-mode-timeout-power",
&cust_cfgs->lpmode_timeout_power);
of_property_read_u32(np_emif,
"low-power-mode-freq-threshold",
&cust_cfgs->lpmode_freq_threshold);
}
if (poll_intvl) {
cust_cfgs->mask |=
EMIF_CUSTOM_CONFIG_TEMP_ALERT_POLL_INTERVAL;
cust_cfgs->temp_alert_poll_interval_ms =
be32_to_cpup(poll_intvl);
}
if (of_find_property(np_emif, "extended-temp-part", &len))
cust_cfgs->mask |= EMIF_CUSTOM_CONFIG_EXTENDED_TEMP_PART;
if (!is_custom_config_valid(cust_cfgs, emif->dev)) {
devm_kfree(emif->dev, cust_cfgs);
return;
}
emif->plat_data->custom_configs = cust_cfgs;
}
static void __init_or_module of_get_ddr_info(struct device_node *np_emif,
struct device_node *np_ddr,
struct ddr_device_info *dev_info)
{
u32 density = 0, io_width = 0;
int len;
if (of_find_property(np_emif, "cs1-used", &len))
dev_info->cs1_used = true;
if (of_find_property(np_emif, "cal-resistor-per-cs", &len))
dev_info->cal_resistors_per_cs = true;
if (of_device_is_compatible(np_ddr, "jedec,lpddr2-s4"))
dev_info->type = DDR_TYPE_LPDDR2_S4;
else if (of_device_is_compatible(np_ddr, "jedec,lpddr2-s2"))
dev_info->type = DDR_TYPE_LPDDR2_S2;
of_property_read_u32(np_ddr, "density", &density);
of_property_read_u32(np_ddr, "io-width", &io_width);
/* Convert from density in Mb to the density encoding in jedc_ddr.h */
if (density & (density - 1))
dev_info->density = 0;
else
dev_info->density = __fls(density) - 5;
/* Convert from io_width in bits to io_width encoding in jedc_ddr.h */
if (io_width & (io_width - 1))
dev_info->io_width = 0;
else
dev_info->io_width = __fls(io_width) - 1;
}
static struct emif_data * __init_or_module of_get_memory_device_details(
struct device_node *np_emif, struct device *dev)
{
struct emif_data *emif = NULL;
struct ddr_device_info *dev_info = NULL;
struct emif_platform_data *pd = NULL;
struct device_node *np_ddr;
int len;
np_ddr = of_parse_phandle(np_emif, "device-handle", 0);
if (!np_ddr)
goto error;
emif = devm_kzalloc(dev, sizeof(struct emif_data), GFP_KERNEL);
pd = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
dev_info = devm_kzalloc(dev, sizeof(*dev_info), GFP_KERNEL);
if (!emif || !pd || !dev_info) {
dev_err(dev, "%s: Out of memory!!\n",
__func__);
goto error;
}
emif->plat_data = pd;
pd->device_info = dev_info;
emif->dev = dev;
emif->np_ddr = np_ddr;
emif->temperature_level = SDRAM_TEMP_NOMINAL;
if (of_device_is_compatible(np_emif, "ti,emif-4d"))
emif->plat_data->ip_rev = EMIF_4D;
else if (of_device_is_compatible(np_emif, "ti,emif-4d5"))
emif->plat_data->ip_rev = EMIF_4D5;
of_property_read_u32(np_emif, "phy-type", &pd->phy_type);
if (of_find_property(np_emif, "hw-caps-ll-interface", &len))
pd->hw_caps |= EMIF_HW_CAPS_LL_INTERFACE;
of_get_ddr_info(np_emif, np_ddr, dev_info);
if (!is_dev_data_valid(pd->device_info->type, pd->device_info->density,
pd->device_info->io_width, pd->phy_type, pd->ip_rev,
emif->dev)) {
dev_err(dev, "%s: invalid device data!!\n", __func__);
goto error;
}
/*
* For EMIF instances other than EMIF1 see if the devices connected
* are exactly same as on EMIF1(which is typically the case). If so,
* mark it as a duplicate of EMIF1. This will save some memory and
* computation.
*/
if (emif1 && emif1->np_ddr == np_ddr) {
emif->duplicate = true;
goto out;
} else if (emif1) {
dev_warn(emif->dev, "%s: Non-symmetric DDR geometry\n",
__func__);
}
of_get_custom_configs(np_emif, emif);
emif->plat_data->timings = of_get_ddr_timings(np_ddr, emif->dev,
emif->plat_data->device_info->type,
&emif->plat_data->timings_arr_size);
emif->plat_data->min_tck = of_get_min_tck(np_ddr, emif->dev);
goto out;
error:
return NULL;
out:
return emif;
}
#else
static struct emif_data * __init_or_module of_get_memory_device_details(
struct device_node *np_emif, struct device *dev)
{
return NULL;
}
#endif
static struct emif_data *__init_or_module get_device_details(
struct platform_device *pdev)
{
u32 size;
struct emif_data *emif = NULL;
struct ddr_device_info *dev_info;
struct emif_custom_configs *cust_cfgs;
struct emif_platform_data *pd;
struct device *dev;
void *temp;
pd = pdev->dev.platform_data;
dev = &pdev->dev;
if (!(pd && pd->device_info && is_dev_data_valid(pd->device_info->type,
pd->device_info->density, pd->device_info->io_width,
pd->phy_type, pd->ip_rev, dev))) {
dev_err(dev, "%s: invalid device data\n", __func__);
goto error;
}
emif = devm_kzalloc(dev, sizeof(*emif), GFP_KERNEL);
temp = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
dev_info = devm_kzalloc(dev, sizeof(*dev_info), GFP_KERNEL);
if (!emif || !temp || !dev_info)
goto error;
memcpy(temp, pd, sizeof(*pd));
pd = temp;
memcpy(dev_info, pd->device_info, sizeof(*dev_info));
pd->device_info = dev_info;
emif->plat_data = pd;
emif->dev = dev;
emif->temperature_level = SDRAM_TEMP_NOMINAL;
/*
* For EMIF instances other than EMIF1 see if the devices connected
* are exactly same as on EMIF1(which is typically the case). If so,
* mark it as a duplicate of EMIF1 and skip copying timings data.
* This will save some memory and some computation later.
*/
emif->duplicate = emif1 && (memcmp(dev_info,
emif1->plat_data->device_info,
sizeof(struct ddr_device_info)) == 0);
if (emif->duplicate) {
pd->timings = NULL;
pd->min_tck = NULL;
goto out;
} else if (emif1) {
dev_warn(emif->dev, "%s: Non-symmetric DDR geometry\n",
__func__);
}
/*
* Copy custom configs - ignore allocation error, if any, as
* custom_configs is not very critical
*/
cust_cfgs = pd->custom_configs;
if (cust_cfgs && is_custom_config_valid(cust_cfgs, dev)) {
temp = devm_kzalloc(dev, sizeof(*cust_cfgs), GFP_KERNEL);
if (temp)
memcpy(temp, cust_cfgs, sizeof(*cust_cfgs));
pd->custom_configs = temp;
}
/*
* Copy timings and min-tck values from platform data. If it is not
* available or if memory allocation fails, use JEDEC defaults
*/
size = sizeof(struct lpddr2_timings) * pd->timings_arr_size;
if (pd->timings) {
temp = devm_kzalloc(dev, size, GFP_KERNEL);
if (temp) {
memcpy(temp, pd->timings, size);
pd->timings = temp;
} else {
get_default_timings(emif);
}
} else {
get_default_timings(emif);
}
if (pd->min_tck) {
temp = devm_kzalloc(dev, sizeof(*pd->min_tck), GFP_KERNEL);
if (temp) {
memcpy(temp, pd->min_tck, sizeof(*pd->min_tck));
pd->min_tck = temp;
} else {
pd->min_tck = &lpddr2_jedec_min_tck;
}
} else {
pd->min_tck = &lpddr2_jedec_min_tck;
}
out:
return emif;
error:
return NULL;
}
static int __init_or_module emif_probe(struct platform_device *pdev)
{
struct emif_data *emif;
int irq, ret;
if (pdev->dev.of_node)
emif = of_get_memory_device_details(pdev->dev.of_node, &pdev->dev);
else
emif = get_device_details(pdev);
if (!emif) {
pr_err("%s: error getting device data\n", __func__);
goto error;
}
list_add(&emif->node, &device_list);
/* Save pointers to each other in emif and device structures */
emif->dev = &pdev->dev;
platform_set_drvdata(pdev, emif);
emif->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(emif->base))
goto error;
irq = platform_get_irq(pdev, 0);
if (irq < 0)
goto error;
emif_onetime_settings(emif);
emif_debugfs_init(emif);
disable_and_clear_all_interrupts(emif);
ret = setup_interrupts(emif, irq);
if (ret)
goto error;
/* One-time actions taken on probing the first device */
if (!emif1) {
emif1 = emif;
/*
* TODO: register notifiers for frequency and voltage
* change here once the respective frameworks are
* available
*/
}
dev_info(&pdev->dev, "%s: device configured with addr = %p and IRQ%d\n",
__func__, emif->base, irq);
return 0;
error:
return -ENODEV;
}
static int __exit emif_remove(struct platform_device *pdev)
{
struct emif_data *emif = platform_get_drvdata(pdev);
emif_debugfs_exit(emif);
return 0;
}
static void emif_shutdown(struct platform_device *pdev)
{
struct emif_data *emif = platform_get_drvdata(pdev);
disable_and_clear_all_interrupts(emif);
}
#if defined(CONFIG_OF)
static const struct of_device_id emif_of_match[] = {
{ .compatible = "ti,emif-4d" },
{ .compatible = "ti,emif-4d5" },
{},
};
MODULE_DEVICE_TABLE(of, emif_of_match);
#endif
static struct platform_driver emif_driver = {
.remove = __exit_p(emif_remove),
.shutdown = emif_shutdown,
.driver = {
.name = "emif",
.of_match_table = of_match_ptr(emif_of_match),
},
};
module_platform_driver_probe(emif_driver, emif_probe);
MODULE_DESCRIPTION("TI EMIF SDRAM Controller Driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:emif");
MODULE_AUTHOR("Texas Instruments Inc");