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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /drivers/memory/emif.c
parentInitial commit. (diff)
downloadlinux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz
linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip
Adding upstream version 5.10.209.upstream/5.10.209
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/memory/emif.c')
-rw-r--r--drivers/memory/emif.c1891
1 files changed, 1891 insertions, 0 deletions
diff --git a/drivers/memory/emif.c b/drivers/memory/emif.c
new file mode 100644
index 000000000..5a059be35
--- /dev/null
+++ b/drivers/memory/emif.c
@@ -0,0 +1,1891 @@
+// 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.
+ * @addressing table with addressing information from the spec
+ * @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;
+ const struct lpddr2_addressing *addressing;
+ 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 spinlock_t emif_lock;
+static unsigned long irq_state;
+static u32 t_ck; /* DDR clock period in ps */
+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
+
+/*
+ * Calculate the period of DDR clock from frequency value
+ */
+static void set_ddr_clk_period(u32 freq)
+{
+ /* Divide 10^12 by frequency to get period in ps */
+ t_ck = (u32)DIV_ROUND_UP_ULL(1000000000000ull, freq);
+}
+
+/*
+ * 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;
+}
+
+/*
+ * Get the CL from SDRAM_CONFIG register
+ */
+static u32 get_cl(struct emif_data *emif)
+{
+ u32 cl;
+ void __iomem *base = emif->base;
+
+ cl = (readl(base + EMIF_SDRAM_CONFIG) & CL_MASK) >> CL_SHIFT;
+
+ return cl;
+}
+
+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];
+}
+
+/*
+ * Find the the right timing table from the array of timing
+ * tables of the device using DDR clock frequency
+ */
+static const struct lpddr2_timings *get_timings_table(struct emif_data *emif,
+ u32 freq)
+{
+ u32 i, min, max, freq_nearest;
+ const struct lpddr2_timings *timings = NULL;
+ const struct lpddr2_timings *timings_arr = emif->plat_data->timings;
+ struct device *dev = emif->dev;
+
+ /* Start with a very high frequency - 1GHz */
+ freq_nearest = 1000000000;
+
+ /*
+ * Find the timings table such that:
+ * 1. the frequency range covers the required frequency(safe) AND
+ * 2. the max_freq is closest to the required frequency(optimal)
+ */
+ for (i = 0; i < emif->plat_data->timings_arr_size; i++) {
+ max = timings_arr[i].max_freq;
+ min = timings_arr[i].min_freq;
+ if ((freq >= min) && (freq <= max) && (max < freq_nearest)) {
+ freq_nearest = max;
+ timings = &timings_arr[i];
+ }
+ }
+
+ if (!timings)
+ dev_err(dev, "%s: couldn't find timings for - %dHz\n",
+ __func__, freq);
+
+ dev_dbg(dev, "%s: timings table: freq %d, speed bin freq %d\n",
+ __func__, freq, freq_nearest);
+
+ return timings;
+}
+
+static u32 get_sdram_ref_ctrl_shdw(u32 freq,
+ const struct lpddr2_addressing *addressing)
+{
+ u32 ref_ctrl_shdw = 0, val = 0, freq_khz, t_refi;
+
+ /* Scale down frequency and t_refi to avoid overflow */
+ freq_khz = freq / 1000;
+ t_refi = addressing->tREFI_ns / 100;
+
+ /*
+ * refresh rate to be set is 'tREFI(in us) * freq in MHz
+ * division by 10000 to account for change in units
+ */
+ val = t_refi * freq_khz / 10000;
+ ref_ctrl_shdw |= val << REFRESH_RATE_SHIFT;
+
+ return ref_ctrl_shdw;
+}
+
+static u32 get_sdram_tim_1_shdw(const struct lpddr2_timings *timings,
+ const struct lpddr2_min_tck *min_tck,
+ const struct lpddr2_addressing *addressing)
+{
+ u32 tim1 = 0, val = 0;
+
+ val = max(min_tck->tWTR, DIV_ROUND_UP(timings->tWTR, t_ck)) - 1;
+ tim1 |= val << T_WTR_SHIFT;
+
+ if (addressing->num_banks == B8)
+ val = DIV_ROUND_UP(timings->tFAW, t_ck*4);
+ else
+ val = max(min_tck->tRRD, DIV_ROUND_UP(timings->tRRD, t_ck));
+ tim1 |= (val - 1) << T_RRD_SHIFT;
+
+ val = DIV_ROUND_UP(timings->tRAS_min + timings->tRPab, t_ck) - 1;
+ tim1 |= val << T_RC_SHIFT;
+
+ val = max(min_tck->tRASmin, DIV_ROUND_UP(timings->tRAS_min, t_ck));
+ tim1 |= (val - 1) << T_RAS_SHIFT;
+
+ val = max(min_tck->tWR, DIV_ROUND_UP(timings->tWR, t_ck)) - 1;
+ tim1 |= val << T_WR_SHIFT;
+
+ val = max(min_tck->tRCD, DIV_ROUND_UP(timings->tRCD, t_ck)) - 1;
+ tim1 |= val << T_RCD_SHIFT;
+
+ val = max(min_tck->tRPab, DIV_ROUND_UP(timings->tRPab, t_ck)) - 1;
+ tim1 |= val << T_RP_SHIFT;
+
+ return tim1;
+}
+
+static u32 get_sdram_tim_1_shdw_derated(const struct lpddr2_timings *timings,
+ const struct lpddr2_min_tck *min_tck,
+ const struct lpddr2_addressing *addressing)
+{
+ u32 tim1 = 0, val = 0;
+
+ val = max(min_tck->tWTR, DIV_ROUND_UP(timings->tWTR, t_ck)) - 1;
+ tim1 = val << T_WTR_SHIFT;
+
+ /*
+ * tFAW is approximately 4 times tRRD. So add 1875*4 = 7500ps
+ * to tFAW for de-rating
+ */
+ if (addressing->num_banks == B8) {
+ val = DIV_ROUND_UP(timings->tFAW + 7500, 4 * t_ck) - 1;
+ } else {
+ val = DIV_ROUND_UP(timings->tRRD + 1875, t_ck);
+ val = max(min_tck->tRRD, val) - 1;
+ }
+ tim1 |= val << T_RRD_SHIFT;
+
+ val = DIV_ROUND_UP(timings->tRAS_min + timings->tRPab + 1875, t_ck);
+ tim1 |= (val - 1) << T_RC_SHIFT;
+
+ val = DIV_ROUND_UP(timings->tRAS_min + 1875, t_ck);
+ val = max(min_tck->tRASmin, val) - 1;
+ tim1 |= val << T_RAS_SHIFT;
+
+ val = max(min_tck->tWR, DIV_ROUND_UP(timings->tWR, t_ck)) - 1;
+ tim1 |= val << T_WR_SHIFT;
+
+ val = max(min_tck->tRCD, DIV_ROUND_UP(timings->tRCD + 1875, t_ck));
+ tim1 |= (val - 1) << T_RCD_SHIFT;
+
+ val = max(min_tck->tRPab, DIV_ROUND_UP(timings->tRPab + 1875, t_ck));
+ tim1 |= (val - 1) << T_RP_SHIFT;
+
+ return tim1;
+}
+
+static u32 get_sdram_tim_2_shdw(const struct lpddr2_timings *timings,
+ const struct lpddr2_min_tck *min_tck,
+ const struct lpddr2_addressing *addressing,
+ u32 type)
+{
+ u32 tim2 = 0, val = 0;
+
+ val = min_tck->tCKE - 1;
+ tim2 |= val << T_CKE_SHIFT;
+
+ val = max(min_tck->tRTP, DIV_ROUND_UP(timings->tRTP, t_ck)) - 1;
+ tim2 |= val << T_RTP_SHIFT;
+
+ /* tXSNR = tRFCab_ps + 10 ns(tRFCab_ps for LPDDR2). */
+ val = DIV_ROUND_UP(addressing->tRFCab_ps + 10000, t_ck) - 1;
+ tim2 |= val << T_XSNR_SHIFT;
+
+ /* XSRD same as XSNR for LPDDR2 */
+ tim2 |= val << T_XSRD_SHIFT;
+
+ val = max(min_tck->tXP, DIV_ROUND_UP(timings->tXP, t_ck)) - 1;
+ tim2 |= val << T_XP_SHIFT;
+
+ return tim2;
+}
+
+static u32 get_sdram_tim_3_shdw(const struct lpddr2_timings *timings,
+ const struct lpddr2_min_tck *min_tck,
+ const struct lpddr2_addressing *addressing,
+ u32 type, u32 ip_rev, u32 derated)
+{
+ u32 tim3 = 0, val = 0, t_dqsck;
+
+ val = timings->tRAS_max_ns / addressing->tREFI_ns - 1;
+ val = val > 0xF ? 0xF : val;
+ tim3 |= val << T_RAS_MAX_SHIFT;
+
+ val = DIV_ROUND_UP(addressing->tRFCab_ps, t_ck) - 1;
+ tim3 |= val << T_RFC_SHIFT;
+
+ t_dqsck = (derated == EMIF_DERATED_TIMINGS) ?
+ timings->tDQSCK_max_derated : timings->tDQSCK_max;
+ if (ip_rev == EMIF_4D5)
+ val = DIV_ROUND_UP(t_dqsck + 1000, t_ck) - 1;
+ else
+ val = DIV_ROUND_UP(t_dqsck, t_ck) - 1;
+
+ tim3 |= val << T_TDQSCKMAX_SHIFT;
+
+ val = DIV_ROUND_UP(timings->tZQCS, t_ck) - 1;
+ tim3 |= val << ZQ_ZQCS_SHIFT;
+
+ val = DIV_ROUND_UP(timings->tCKESR, t_ck);
+ val = max(min_tck->tCKESR, val) - 1;
+ tim3 |= val << T_CKESR_SHIFT;
+
+ if (ip_rev == EMIF_4D5) {
+ tim3 |= (EMIF_T_CSTA - 1) << T_CSTA_SHIFT;
+
+ val = DIV_ROUND_UP(EMIF_T_PDLL_UL, 128) - 1;
+ tim3 |= val << T_PDLL_UL_SHIFT;
+ }
+
+ return tim3;
+}
+
+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_read_idle_ctrl_shdw(u8 volt_ramp)
+{
+ u32 idle = 0, val = 0;
+
+ /*
+ * Maximum value in normal conditions and increased frequency
+ * when voltage is ramping
+ */
+ if (volt_ramp)
+ val = READ_IDLE_INTERVAL_DVFS / t_ck / 64 - 1;
+ else
+ val = 0x1FF;
+
+ /*
+ * READ_IDLE_CTRL register in EMIF4D has same offset and fields
+ * as DLL_CALIB_CTRL in EMIF4D5, so use the same shifts
+ */
+ idle |= val << DLL_CALIB_INTERVAL_SHIFT;
+ idle |= EMIF_READ_IDLE_LEN_VAL << ACK_WAIT_SHIFT;
+
+ return idle;
+}
+
+static u32 get_dll_calib_ctrl_shdw(u8 volt_ramp)
+{
+ u32 calib = 0, val = 0;
+
+ if (volt_ramp == DDR_VOLTAGE_RAMPING)
+ val = DLL_CALIB_INTERVAL_DVFS / t_ck / 16 - 1;
+ else
+ val = 0; /* Disabled when voltage is stable */
+
+ calib |= val << DLL_CALIB_INTERVAL_SHIFT;
+ calib |= DLL_CALIB_ACK_WAIT_VAL << ACK_WAIT_SHIFT;
+
+ return calib;
+}
+
+static u32 get_ddr_phy_ctrl_1_attilaphy_4d(const struct lpddr2_timings *timings,
+ u32 freq, u8 RL)
+{
+ u32 phy = EMIF_DDR_PHY_CTRL_1_BASE_VAL_ATTILAPHY, val = 0;
+
+ val = RL + DIV_ROUND_UP(timings->tDQSCK_max, t_ck) - 1;
+ phy |= val << READ_LATENCY_SHIFT_4D;
+
+ if (freq <= 100000000)
+ val = EMIF_DLL_SLAVE_DLY_CTRL_100_MHZ_AND_LESS_ATTILAPHY;
+ else if (freq <= 200000000)
+ val = EMIF_DLL_SLAVE_DLY_CTRL_200_MHZ_ATTILAPHY;
+ else
+ val = EMIF_DLL_SLAVE_DLY_CTRL_400_MHZ_ATTILAPHY;
+
+ phy |= val << DLL_SLAVE_DLY_CTRL_SHIFT_4D;
+
+ return phy;
+}
+
+static u32 get_phy_ctrl_1_intelliphy_4d5(u32 freq, u8 cl)
+{
+ u32 phy = EMIF_DDR_PHY_CTRL_1_BASE_VAL_INTELLIPHY, half_delay;
+
+ /*
+ * DLL operates at 266 MHz. If DDR frequency is near 266 MHz,
+ * half-delay is not needed else set half-delay
+ */
+ if (freq >= 265000000 && freq < 267000000)
+ half_delay = 0;
+ else
+ half_delay = 1;
+
+ phy |= half_delay << DLL_HALF_DELAY_SHIFT_4D5;
+ phy |= ((cl + DIV_ROUND_UP(EMIF_PHY_TOTAL_READ_LATENCY_INTELLIPHY_PS,
+ t_ck) - 1) << READ_LATENCY_SHIFT_4D5);
+
+ return phy;
+}
+
+static u32 get_ext_phy_ctrl_2_intelliphy_4d5(void)
+{
+ u32 fifo_we_slave_ratio;
+
+ fifo_we_slave_ratio = DIV_ROUND_CLOSEST(
+ EMIF_INTELLI_PHY_DQS_GATE_OPENING_DELAY_PS * 256, t_ck);
+
+ return fifo_we_slave_ratio | fifo_we_slave_ratio << 11 |
+ fifo_we_slave_ratio << 22;
+}
+
+static u32 get_ext_phy_ctrl_3_intelliphy_4d5(void)
+{
+ u32 fifo_we_slave_ratio;
+
+ fifo_we_slave_ratio = DIV_ROUND_CLOSEST(
+ EMIF_INTELLI_PHY_DQS_GATE_OPENING_DELAY_PS * 256, t_ck);
+
+ return fifo_we_slave_ratio >> 10 | fifo_we_slave_ratio << 1 |
+ fifo_we_slave_ratio << 12 | fifo_we_slave_ratio << 23;
+}
+
+static u32 get_ext_phy_ctrl_4_intelliphy_4d5(void)
+{
+ u32 fifo_we_slave_ratio;
+
+ fifo_we_slave_ratio = DIV_ROUND_CLOSEST(
+ EMIF_INTELLI_PHY_DQS_GATE_OPENING_DELAY_PS * 256, t_ck);
+
+ return fifo_we_slave_ratio >> 9 | fifo_we_slave_ratio << 2 |
+ fifo_we_slave_ratio << 13;
+}
+
+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;
+}
+
+/*
+ * Program EMIF shadow registers that are not dependent on temperature
+ * or voltage
+ */
+static void setup_registers(struct emif_data *emif, struct emif_regs *regs)
+{
+ void __iomem *base = emif->base;
+
+ writel(regs->sdram_tim2_shdw, base + EMIF_SDRAM_TIMING_2_SHDW);
+ writel(regs->phy_ctrl_1_shdw, base + EMIF_DDR_PHY_CTRL_1_SHDW);
+ writel(regs->pwr_mgmt_ctrl_shdw,
+ base + EMIF_POWER_MANAGEMENT_CTRL_SHDW);
+
+ /* Settings specific for EMIF4D5 */
+ if (emif->plat_data->ip_rev != EMIF_4D5)
+ return;
+ writel(regs->ext_phy_ctrl_2_shdw, base + EMIF_EXT_PHY_CTRL_2_SHDW);
+ writel(regs->ext_phy_ctrl_3_shdw, base + EMIF_EXT_PHY_CTRL_3_SHDW);
+ writel(regs->ext_phy_ctrl_4_shdw, base + EMIF_EXT_PHY_CTRL_4_SHDW);
+}
+
+/*
+ * When voltage ramps dll calibration and forced read idle should
+ * happen more often
+ */
+static void setup_volt_sensitive_regs(struct emif_data *emif,
+ struct emif_regs *regs, u32 volt_state)
+{
+ u32 calib_ctrl;
+ void __iomem *base = emif->base;
+
+ /*
+ * EMIF_READ_IDLE_CTRL in EMIF4D refers to the same register as
+ * EMIF_DLL_CALIB_CTRL in EMIF4D5 and dll_calib_ctrl_shadow_*
+ * is an alias of the respective read_idle_ctrl_shdw_* (members of
+ * a union). So, the below code takes care of both cases
+ */
+ if (volt_state == DDR_VOLTAGE_RAMPING)
+ calib_ctrl = regs->dll_calib_ctrl_shdw_volt_ramp;
+ else
+ calib_ctrl = regs->dll_calib_ctrl_shdw_normal;
+
+ writel(calib_ctrl, base + EMIF_DLL_CALIB_CTRL_SHDW);
+}
+
+/*
+ * 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 (pm_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) {
+ dev_err(dev, "%s:%d: allocation error\n", __func__, __LINE__);
+ 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));
+ else
+ dev_warn(dev, "%s:%d: allocation error\n", __func__,
+ __LINE__);
+ 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 {
+ dev_warn(dev, "%s:%d: allocation error\n", __func__,
+ __LINE__);
+ 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 {
+ dev_warn(dev, "%s:%d: allocation error\n", __func__,
+ __LINE__);
+ 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;
+ struct resource *res;
+ 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);
+ emif->addressing = get_addressing_table(emif->plat_data->device_info);
+
+ /* Save pointers to each other in emif and device structures */
+ emif->dev = &pdev->dev;
+ platform_set_drvdata(pdev, emif);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ emif->base = devm_ioremap_resource(emif->dev, res);
+ 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;
+ spin_lock_init(&emif_lock);
+
+ /*
+ * 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);
+}
+
+static int get_emif_reg_values(struct emif_data *emif, u32 freq,
+ struct emif_regs *regs)
+{
+ u32 ip_rev, phy_type;
+ u32 cl, type;
+ const struct lpddr2_timings *timings;
+ const struct lpddr2_min_tck *min_tck;
+ const struct ddr_device_info *device_info;
+ const struct lpddr2_addressing *addressing;
+ struct emif_data *emif_for_calc;
+ struct device *dev;
+
+ dev = emif->dev;
+ /*
+ * If the devices on this EMIF instance is duplicate of EMIF1,
+ * use EMIF1 details for the calculation
+ */
+ emif_for_calc = emif->duplicate ? emif1 : emif;
+ timings = get_timings_table(emif_for_calc, freq);
+ addressing = emif_for_calc->addressing;
+ if (!timings || !addressing) {
+ dev_err(dev, "%s: not enough data available for %dHz",
+ __func__, freq);
+ return -1;
+ }
+
+ device_info = emif_for_calc->plat_data->device_info;
+ type = device_info->type;
+ ip_rev = emif_for_calc->plat_data->ip_rev;
+ phy_type = emif_for_calc->plat_data->phy_type;
+
+ min_tck = emif_for_calc->plat_data->min_tck;
+
+ set_ddr_clk_period(freq);
+
+ regs->ref_ctrl_shdw = get_sdram_ref_ctrl_shdw(freq, addressing);
+ regs->sdram_tim1_shdw = get_sdram_tim_1_shdw(timings, min_tck,
+ addressing);
+ regs->sdram_tim2_shdw = get_sdram_tim_2_shdw(timings, min_tck,
+ addressing, type);
+ regs->sdram_tim3_shdw = get_sdram_tim_3_shdw(timings, min_tck,
+ addressing, type, ip_rev, EMIF_NORMAL_TIMINGS);
+
+ cl = get_cl(emif);
+
+ if (phy_type == EMIF_PHY_TYPE_ATTILAPHY && ip_rev == EMIF_4D) {
+ regs->phy_ctrl_1_shdw = get_ddr_phy_ctrl_1_attilaphy_4d(
+ timings, freq, cl);
+ } else if (phy_type == EMIF_PHY_TYPE_INTELLIPHY && ip_rev == EMIF_4D5) {
+ regs->phy_ctrl_1_shdw = get_phy_ctrl_1_intelliphy_4d5(freq, cl);
+ regs->ext_phy_ctrl_2_shdw = get_ext_phy_ctrl_2_intelliphy_4d5();
+ regs->ext_phy_ctrl_3_shdw = get_ext_phy_ctrl_3_intelliphy_4d5();
+ regs->ext_phy_ctrl_4_shdw = get_ext_phy_ctrl_4_intelliphy_4d5();
+ } else {
+ return -1;
+ }
+
+ /* Only timeout values in pwr_mgmt_ctrl_shdw register */
+ regs->pwr_mgmt_ctrl_shdw =
+ get_pwr_mgmt_ctrl(freq, emif_for_calc, ip_rev) &
+ (CS_TIM_MASK | SR_TIM_MASK | PD_TIM_MASK);
+
+ if (ip_rev & EMIF_4D) {
+ regs->read_idle_ctrl_shdw_normal =
+ get_read_idle_ctrl_shdw(DDR_VOLTAGE_STABLE);
+
+ regs->read_idle_ctrl_shdw_volt_ramp =
+ get_read_idle_ctrl_shdw(DDR_VOLTAGE_RAMPING);
+ } else if (ip_rev & EMIF_4D5) {
+ regs->dll_calib_ctrl_shdw_normal =
+ get_dll_calib_ctrl_shdw(DDR_VOLTAGE_STABLE);
+
+ regs->dll_calib_ctrl_shdw_volt_ramp =
+ get_dll_calib_ctrl_shdw(DDR_VOLTAGE_RAMPING);
+ }
+
+ if (type == DDR_TYPE_LPDDR2_S2 || type == DDR_TYPE_LPDDR2_S4) {
+ regs->ref_ctrl_shdw_derated = get_sdram_ref_ctrl_shdw(freq / 4,
+ addressing);
+
+ regs->sdram_tim1_shdw_derated =
+ get_sdram_tim_1_shdw_derated(timings, min_tck,
+ addressing);
+
+ regs->sdram_tim3_shdw_derated = get_sdram_tim_3_shdw(timings,
+ min_tck, addressing, type, ip_rev,
+ EMIF_DERATED_TIMINGS);
+ }
+
+ regs->freq = freq;
+
+ return 0;
+}
+
+/*
+ * get_regs() - gets the cached emif_regs structure for a given EMIF instance
+ * given frequency(freq):
+ *
+ * As an optimisation, every EMIF instance other than EMIF1 shares the
+ * register cache with EMIF1 if the devices connected on this instance
+ * are same as that on EMIF1(indicated by the duplicate flag)
+ *
+ * If we do not have an entry corresponding to the frequency given, we
+ * allocate a new entry and calculate the values
+ *
+ * Upon finding the right reg dump, save it in curr_regs. It can be
+ * directly used for thermal de-rating and voltage ramping changes.
+ */
+static struct emif_regs *get_regs(struct emif_data *emif, u32 freq)
+{
+ int i;
+ struct emif_regs **regs_cache;
+ struct emif_regs *regs = NULL;
+ struct device *dev;
+
+ dev = emif->dev;
+ if (emif->curr_regs && emif->curr_regs->freq == freq) {
+ dev_dbg(dev, "%s: using curr_regs - %u Hz", __func__, freq);
+ return emif->curr_regs;
+ }
+
+ 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++) {
+ if (regs_cache[i]->freq == freq) {
+ regs = regs_cache[i];
+ dev_dbg(dev,
+ "%s: reg dump found in reg cache for %u Hz\n",
+ __func__, freq);
+ break;
+ }
+ }
+
+ /*
+ * If we don't have an entry for this frequency in the cache create one
+ * and calculate the values
+ */
+ if (!regs) {
+ regs = devm_kzalloc(emif->dev, sizeof(*regs), GFP_ATOMIC);
+ if (!regs)
+ return NULL;
+
+ if (get_emif_reg_values(emif, freq, regs)) {
+ devm_kfree(emif->dev, regs);
+ return NULL;
+ }
+
+ /*
+ * Now look for an un-used entry in the cache and save the
+ * newly created struct. If there are no free entries
+ * over-write the last entry
+ */
+ for (i = 0; i < EMIF_MAX_NUM_FREQUENCIES && regs_cache[i]; i++)
+ ;
+
+ if (i >= EMIF_MAX_NUM_FREQUENCIES) {
+ dev_warn(dev, "%s: regs_cache full - reusing a slot!!\n",
+ __func__);
+ i = EMIF_MAX_NUM_FREQUENCIES - 1;
+ devm_kfree(emif->dev, regs_cache[i]);
+ }
+ regs_cache[i] = regs;
+ }
+
+ return regs;
+}
+
+static void do_volt_notify_handling(struct emif_data *emif, u32 volt_state)
+{
+ dev_dbg(emif->dev, "%s: voltage notification : %d", __func__,
+ volt_state);
+
+ if (!emif->curr_regs) {
+ dev_err(emif->dev,
+ "%s: volt-notify before registers are ready: %d\n",
+ __func__, volt_state);
+ return;
+ }
+
+ setup_volt_sensitive_regs(emif, emif->curr_regs, volt_state);
+}
+
+/*
+ * TODO: voltage notify handling should be hooked up to
+ * regulator framework as soon as the necessary support
+ * is available in mainline kernel. This function is un-used
+ * right now.
+ */
+static void __attribute__((unused)) volt_notify_handling(u32 volt_state)
+{
+ struct emif_data *emif;
+
+ spin_lock_irqsave(&emif_lock, irq_state);
+
+ list_for_each_entry(emif, &device_list, node)
+ do_volt_notify_handling(emif, volt_state);
+ do_freq_update();
+
+ spin_unlock_irqrestore(&emif_lock, irq_state);
+}
+
+static void do_freq_pre_notify_handling(struct emif_data *emif, u32 new_freq)
+{
+ struct emif_regs *regs;
+
+ regs = get_regs(emif, new_freq);
+ if (!regs)
+ return;
+
+ emif->curr_regs = regs;
+
+ /*
+ * Update the shadow registers:
+ * Temperature and voltage-ramp sensitive settings are also configured
+ * in terms of DDR cycles. So, we need to update them too when there
+ * is a freq change
+ */
+ dev_dbg(emif->dev, "%s: setting up shadow registers for %uHz",
+ __func__, new_freq);
+ setup_registers(emif, regs);
+ setup_temperature_sensitive_regs(emif, regs);
+ setup_volt_sensitive_regs(emif, regs, DDR_VOLTAGE_STABLE);
+
+ /*
+ * Part of workaround for errata i728. See do_freq_update()
+ * for more details
+ */
+ if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
+ set_lpmode(emif, EMIF_LP_MODE_DISABLE);
+}
+
+/*
+ * TODO: frequency notify handling should be hooked up to
+ * clock framework as soon as the necessary support is
+ * available in mainline kernel. This function is un-used
+ * right now.
+ */
+static void __attribute__((unused)) freq_pre_notify_handling(u32 new_freq)
+{
+ struct emif_data *emif;
+
+ /*
+ * NOTE: we are taking the spin-lock here and releases it
+ * only in post-notifier. This doesn't look good and
+ * Sparse complains about it, but this seems to be
+ * un-avoidable. We need to lock a sequence of events
+ * that is split between EMIF and clock framework.
+ *
+ * 1. EMIF driver updates EMIF timings in shadow registers in the
+ * frequency pre-notify callback from clock framework
+ * 2. clock framework sets up the registers for the new frequency
+ * 3. clock framework initiates a hw-sequence that updates
+ * the frequency EMIF timings synchronously.
+ *
+ * All these 3 steps should be performed as an atomic operation
+ * vis-a-vis similar sequence in the EMIF interrupt handler
+ * for temperature events. Otherwise, there could be race
+ * conditions that could result in incorrect EMIF timings for
+ * a given frequency
+ */
+ spin_lock_irqsave(&emif_lock, irq_state);
+
+ list_for_each_entry(emif, &device_list, node)
+ do_freq_pre_notify_handling(emif, new_freq);
+}
+
+static void do_freq_post_notify_handling(struct emif_data *emif)
+{
+ /*
+ * Part of workaround for errata i728. See do_freq_update()
+ * for more details
+ */
+ if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
+ set_lpmode(emif, EMIF_LP_MODE_SELF_REFRESH);
+}
+
+/*
+ * TODO: frequency notify handling should be hooked up to
+ * clock framework as soon as the necessary support is
+ * available in mainline kernel. This function is un-used
+ * right now.
+ */
+static void __attribute__((unused)) freq_post_notify_handling(void)
+{
+ struct emif_data *emif;
+
+ list_for_each_entry(emif, &device_list, node)
+ do_freq_post_notify_handling(emif);
+
+ /*
+ * Lock is done in pre-notify handler. See freq_pre_notify_handling()
+ * for more details
+ */
+ spin_unlock_irqrestore(&emif_lock, irq_state);
+}
+
+#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");