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Diffstat (limited to '')
| -rw-r--r-- | drivers/memory/tegra/tegra30-emc.c | 1764 |
1 files changed, 1764 insertions, 0 deletions
diff --git a/drivers/memory/tegra/tegra30-emc.c b/drivers/memory/tegra/tegra30-emc.c new file mode 100644 index 000000000..1ea3792be --- /dev/null +++ b/drivers/memory/tegra/tegra30-emc.c @@ -0,0 +1,1764 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Tegra30 External Memory Controller driver + * + * Based on downstream driver from NVIDIA and tegra124-emc.c + * Copyright (C) 2011-2014 NVIDIA Corporation + * + * Author: Dmitry Osipenko <digetx@gmail.com> + * Copyright (C) 2019 GRATE-DRIVER project + */ + +#include <linux/bitfield.h> +#include <linux/clk.h> +#include <linux/clk/tegra.h> +#include <linux/debugfs.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/interconnect-provider.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/pm_opp.h> +#include <linux/slab.h> +#include <linux/sort.h> +#include <linux/types.h> + +#include <soc/tegra/common.h> +#include <soc/tegra/fuse.h> + +#include "../jedec_ddr.h" +#include "../of_memory.h" + +#include "mc.h" + +#define EMC_INTSTATUS 0x000 +#define EMC_INTMASK 0x004 +#define EMC_DBG 0x008 +#define EMC_ADR_CFG 0x010 +#define EMC_CFG 0x00c +#define EMC_REFCTRL 0x020 +#define EMC_TIMING_CONTROL 0x028 +#define EMC_RC 0x02c +#define EMC_RFC 0x030 +#define EMC_RAS 0x034 +#define EMC_RP 0x038 +#define EMC_R2W 0x03c +#define EMC_W2R 0x040 +#define EMC_R2P 0x044 +#define EMC_W2P 0x048 +#define EMC_RD_RCD 0x04c +#define EMC_WR_RCD 0x050 +#define EMC_RRD 0x054 +#define EMC_REXT 0x058 +#define EMC_WDV 0x05c +#define EMC_QUSE 0x060 +#define EMC_QRST 0x064 +#define EMC_QSAFE 0x068 +#define EMC_RDV 0x06c +#define EMC_REFRESH 0x070 +#define EMC_BURST_REFRESH_NUM 0x074 +#define EMC_PDEX2WR 0x078 +#define EMC_PDEX2RD 0x07c +#define EMC_PCHG2PDEN 0x080 +#define EMC_ACT2PDEN 0x084 +#define EMC_AR2PDEN 0x088 +#define EMC_RW2PDEN 0x08c +#define EMC_TXSR 0x090 +#define EMC_TCKE 0x094 +#define EMC_TFAW 0x098 +#define EMC_TRPAB 0x09c +#define EMC_TCLKSTABLE 0x0a0 +#define EMC_TCLKSTOP 0x0a4 +#define EMC_TREFBW 0x0a8 +#define EMC_QUSE_EXTRA 0x0ac +#define EMC_ODT_WRITE 0x0b0 +#define EMC_ODT_READ 0x0b4 +#define EMC_WEXT 0x0b8 +#define EMC_CTT 0x0bc +#define EMC_MRS_WAIT_CNT 0x0c8 +#define EMC_MRS 0x0cc +#define EMC_EMRS 0x0d0 +#define EMC_SELF_REF 0x0e0 +#define EMC_MRW 0x0e8 +#define EMC_MRR 0x0ec +#define EMC_XM2DQSPADCTRL3 0x0f8 +#define EMC_FBIO_SPARE 0x100 +#define EMC_FBIO_CFG5 0x104 +#define EMC_FBIO_CFG6 0x114 +#define EMC_CFG_RSV 0x120 +#define EMC_AUTO_CAL_CONFIG 0x2a4 +#define EMC_AUTO_CAL_INTERVAL 0x2a8 +#define EMC_AUTO_CAL_STATUS 0x2ac +#define EMC_STATUS 0x2b4 +#define EMC_CFG_2 0x2b8 +#define EMC_CFG_DIG_DLL 0x2bc +#define EMC_CFG_DIG_DLL_PERIOD 0x2c0 +#define EMC_CTT_DURATION 0x2d8 +#define EMC_CTT_TERM_CTRL 0x2dc +#define EMC_ZCAL_INTERVAL 0x2e0 +#define EMC_ZCAL_WAIT_CNT 0x2e4 +#define EMC_ZQ_CAL 0x2ec +#define EMC_XM2CMDPADCTRL 0x2f0 +#define EMC_XM2DQSPADCTRL2 0x2fc +#define EMC_XM2DQPADCTRL2 0x304 +#define EMC_XM2CLKPADCTRL 0x308 +#define EMC_XM2COMPPADCTRL 0x30c +#define EMC_XM2VTTGENPADCTRL 0x310 +#define EMC_XM2VTTGENPADCTRL2 0x314 +#define EMC_XM2QUSEPADCTRL 0x318 +#define EMC_DLL_XFORM_DQS0 0x328 +#define EMC_DLL_XFORM_DQS1 0x32c +#define EMC_DLL_XFORM_DQS2 0x330 +#define EMC_DLL_XFORM_DQS3 0x334 +#define EMC_DLL_XFORM_DQS4 0x338 +#define EMC_DLL_XFORM_DQS5 0x33c +#define EMC_DLL_XFORM_DQS6 0x340 +#define EMC_DLL_XFORM_DQS7 0x344 +#define EMC_DLL_XFORM_QUSE0 0x348 +#define EMC_DLL_XFORM_QUSE1 0x34c +#define EMC_DLL_XFORM_QUSE2 0x350 +#define EMC_DLL_XFORM_QUSE3 0x354 +#define EMC_DLL_XFORM_QUSE4 0x358 +#define EMC_DLL_XFORM_QUSE5 0x35c +#define EMC_DLL_XFORM_QUSE6 0x360 +#define EMC_DLL_XFORM_QUSE7 0x364 +#define EMC_DLL_XFORM_DQ0 0x368 +#define EMC_DLL_XFORM_DQ1 0x36c +#define EMC_DLL_XFORM_DQ2 0x370 +#define EMC_DLL_XFORM_DQ3 0x374 +#define EMC_DLI_TRIM_TXDQS0 0x3a8 +#define EMC_DLI_TRIM_TXDQS1 0x3ac +#define EMC_DLI_TRIM_TXDQS2 0x3b0 +#define EMC_DLI_TRIM_TXDQS3 0x3b4 +#define EMC_DLI_TRIM_TXDQS4 0x3b8 +#define EMC_DLI_TRIM_TXDQS5 0x3bc +#define EMC_DLI_TRIM_TXDQS6 0x3c0 +#define EMC_DLI_TRIM_TXDQS7 0x3c4 +#define EMC_STALL_THEN_EXE_BEFORE_CLKCHANGE 0x3c8 +#define EMC_STALL_THEN_EXE_AFTER_CLKCHANGE 0x3cc +#define EMC_UNSTALL_RW_AFTER_CLKCHANGE 0x3d0 +#define EMC_SEL_DPD_CTRL 0x3d8 +#define EMC_PRE_REFRESH_REQ_CNT 0x3dc +#define EMC_DYN_SELF_REF_CONTROL 0x3e0 +#define EMC_TXSRDLL 0x3e4 + +#define EMC_STATUS_TIMING_UPDATE_STALLED BIT(23) + +#define EMC_MODE_SET_DLL_RESET BIT(8) +#define EMC_MODE_SET_LONG_CNT BIT(26) + +#define EMC_SELF_REF_CMD_ENABLED BIT(0) + +#define DRAM_DEV_SEL_ALL (0 << 30) +#define DRAM_DEV_SEL_0 BIT(31) +#define DRAM_DEV_SEL_1 BIT(30) +#define DRAM_BROADCAST(num) \ + ((num) > 1 ? DRAM_DEV_SEL_ALL : DRAM_DEV_SEL_0) + +#define EMC_ZQ_CAL_CMD BIT(0) +#define EMC_ZQ_CAL_LONG BIT(4) +#define EMC_ZQ_CAL_LONG_CMD_DEV0 \ + (DRAM_DEV_SEL_0 | EMC_ZQ_CAL_LONG | EMC_ZQ_CAL_CMD) +#define EMC_ZQ_CAL_LONG_CMD_DEV1 \ + (DRAM_DEV_SEL_1 | EMC_ZQ_CAL_LONG | EMC_ZQ_CAL_CMD) + +#define EMC_DBG_READ_MUX_ASSEMBLY BIT(0) +#define EMC_DBG_WRITE_MUX_ACTIVE BIT(1) +#define EMC_DBG_FORCE_UPDATE BIT(2) +#define EMC_DBG_CFG_PRIORITY BIT(24) + +#define EMC_CFG5_QUSE_MODE_SHIFT 13 +#define EMC_CFG5_QUSE_MODE_MASK (7 << EMC_CFG5_QUSE_MODE_SHIFT) + +#define EMC_CFG5_QUSE_MODE_INTERNAL_LPBK 2 +#define EMC_CFG5_QUSE_MODE_PULSE_INTERN 3 + +#define EMC_SEL_DPD_CTRL_QUSE_DPD_ENABLE BIT(9) + +#define EMC_XM2COMPPADCTRL_VREF_CAL_ENABLE BIT(10) + +#define EMC_XM2QUSEPADCTRL_IVREF_ENABLE BIT(4) + +#define EMC_XM2DQSPADCTRL2_VREF_ENABLE BIT(5) +#define EMC_XM2DQSPADCTRL3_VREF_ENABLE BIT(5) + +#define EMC_AUTO_CAL_STATUS_ACTIVE BIT(31) + +#define EMC_FBIO_CFG5_DRAM_TYPE_MASK 0x3 + +#define EMC_MRS_WAIT_CNT_SHORT_WAIT_MASK 0x3ff +#define EMC_MRS_WAIT_CNT_LONG_WAIT_SHIFT 16 +#define EMC_MRS_WAIT_CNT_LONG_WAIT_MASK \ + (0x3ff << EMC_MRS_WAIT_CNT_LONG_WAIT_SHIFT) + +#define EMC_REFCTRL_DEV_SEL_MASK 0x3 +#define EMC_REFCTRL_ENABLE BIT(31) +#define EMC_REFCTRL_ENABLE_ALL(num) \ + (((num) > 1 ? 0 : 2) | EMC_REFCTRL_ENABLE) +#define EMC_REFCTRL_DISABLE_ALL(num) ((num) > 1 ? 0 : 2) + +#define EMC_CFG_PERIODIC_QRST BIT(21) +#define EMC_CFG_DYN_SREF_ENABLE BIT(28) + +#define EMC_CLKCHANGE_REQ_ENABLE BIT(0) +#define EMC_CLKCHANGE_PD_ENABLE BIT(1) +#define EMC_CLKCHANGE_SR_ENABLE BIT(2) + +#define EMC_TIMING_UPDATE BIT(0) + +#define EMC_REFRESH_OVERFLOW_INT BIT(3) +#define EMC_CLKCHANGE_COMPLETE_INT BIT(4) +#define EMC_MRR_DIVLD_INT BIT(5) + +#define EMC_MRR_DEV_SELECTN GENMASK(31, 30) +#define EMC_MRR_MRR_MA GENMASK(23, 16) +#define EMC_MRR_MRR_DATA GENMASK(15, 0) + +#define EMC_ADR_CFG_EMEM_NUMDEV BIT(0) + +enum emc_dram_type { + DRAM_TYPE_DDR3, + DRAM_TYPE_DDR1, + DRAM_TYPE_LPDDR2, + DRAM_TYPE_DDR2, +}; + +enum emc_dll_change { + DLL_CHANGE_NONE, + DLL_CHANGE_ON, + DLL_CHANGE_OFF +}; + +static const u16 emc_timing_registers[] = { + [0] = EMC_RC, + [1] = EMC_RFC, + [2] = EMC_RAS, + [3] = EMC_RP, + [4] = EMC_R2W, + [5] = EMC_W2R, + [6] = EMC_R2P, + [7] = EMC_W2P, + [8] = EMC_RD_RCD, + [9] = EMC_WR_RCD, + [10] = EMC_RRD, + [11] = EMC_REXT, + [12] = EMC_WEXT, + [13] = EMC_WDV, + [14] = EMC_QUSE, + [15] = EMC_QRST, + [16] = EMC_QSAFE, + [17] = EMC_RDV, + [18] = EMC_REFRESH, + [19] = EMC_BURST_REFRESH_NUM, + [20] = EMC_PRE_REFRESH_REQ_CNT, + [21] = EMC_PDEX2WR, + [22] = EMC_PDEX2RD, + [23] = EMC_PCHG2PDEN, + [24] = EMC_ACT2PDEN, + [25] = EMC_AR2PDEN, + [26] = EMC_RW2PDEN, + [27] = EMC_TXSR, + [28] = EMC_TXSRDLL, + [29] = EMC_TCKE, + [30] = EMC_TFAW, + [31] = EMC_TRPAB, + [32] = EMC_TCLKSTABLE, + [33] = EMC_TCLKSTOP, + [34] = EMC_TREFBW, + [35] = EMC_QUSE_EXTRA, + [36] = EMC_FBIO_CFG6, + [37] = EMC_ODT_WRITE, + [38] = EMC_ODT_READ, + [39] = EMC_FBIO_CFG5, + [40] = EMC_CFG_DIG_DLL, + [41] = EMC_CFG_DIG_DLL_PERIOD, + [42] = EMC_DLL_XFORM_DQS0, + [43] = EMC_DLL_XFORM_DQS1, + [44] = EMC_DLL_XFORM_DQS2, + [45] = EMC_DLL_XFORM_DQS3, + [46] = EMC_DLL_XFORM_DQS4, + [47] = EMC_DLL_XFORM_DQS5, + [48] = EMC_DLL_XFORM_DQS6, + [49] = EMC_DLL_XFORM_DQS7, + [50] = EMC_DLL_XFORM_QUSE0, + [51] = EMC_DLL_XFORM_QUSE1, + [52] = EMC_DLL_XFORM_QUSE2, + [53] = EMC_DLL_XFORM_QUSE3, + [54] = EMC_DLL_XFORM_QUSE4, + [55] = EMC_DLL_XFORM_QUSE5, + [56] = EMC_DLL_XFORM_QUSE6, + [57] = EMC_DLL_XFORM_QUSE7, + [58] = EMC_DLI_TRIM_TXDQS0, + [59] = EMC_DLI_TRIM_TXDQS1, + [60] = EMC_DLI_TRIM_TXDQS2, + [61] = EMC_DLI_TRIM_TXDQS3, + [62] = EMC_DLI_TRIM_TXDQS4, + [63] = EMC_DLI_TRIM_TXDQS5, + [64] = EMC_DLI_TRIM_TXDQS6, + [65] = EMC_DLI_TRIM_TXDQS7, + [66] = EMC_DLL_XFORM_DQ0, + [67] = EMC_DLL_XFORM_DQ1, + [68] = EMC_DLL_XFORM_DQ2, + [69] = EMC_DLL_XFORM_DQ3, + [70] = EMC_XM2CMDPADCTRL, + [71] = EMC_XM2DQSPADCTRL2, + [72] = EMC_XM2DQPADCTRL2, + [73] = EMC_XM2CLKPADCTRL, + [74] = EMC_XM2COMPPADCTRL, + [75] = EMC_XM2VTTGENPADCTRL, + [76] = EMC_XM2VTTGENPADCTRL2, + [77] = EMC_XM2QUSEPADCTRL, + [78] = EMC_XM2DQSPADCTRL3, + [79] = EMC_CTT_TERM_CTRL, + [80] = EMC_ZCAL_INTERVAL, + [81] = EMC_ZCAL_WAIT_CNT, + [82] = EMC_MRS_WAIT_CNT, + [83] = EMC_AUTO_CAL_CONFIG, + [84] = EMC_CTT, + [85] = EMC_CTT_DURATION, + [86] = EMC_DYN_SELF_REF_CONTROL, + [87] = EMC_FBIO_SPARE, + [88] = EMC_CFG_RSV, +}; + +struct emc_timing { + unsigned long rate; + + u32 data[ARRAY_SIZE(emc_timing_registers)]; + + u32 emc_auto_cal_interval; + u32 emc_mode_1; + u32 emc_mode_2; + u32 emc_mode_reset; + u32 emc_zcal_cnt_long; + bool emc_cfg_periodic_qrst; + bool emc_cfg_dyn_self_ref; +}; + +enum emc_rate_request_type { + EMC_RATE_DEBUG, + EMC_RATE_ICC, + EMC_RATE_TYPE_MAX, +}; + +struct emc_rate_request { + unsigned long min_rate; + unsigned long max_rate; +}; + +struct tegra_emc { + struct device *dev; + struct tegra_mc *mc; + struct icc_provider provider; + struct notifier_block clk_nb; + struct clk *clk; + void __iomem *regs; + unsigned int irq; + bool bad_state; + + struct emc_timing *new_timing; + struct emc_timing *timings; + unsigned int num_timings; + + u32 mc_override; + u32 emc_cfg; + + u32 emc_mode_1; + u32 emc_mode_2; + u32 emc_mode_reset; + + bool vref_cal_toggle : 1; + bool zcal_long : 1; + bool dll_on : 1; + + struct { + struct dentry *root; + unsigned long min_rate; + unsigned long max_rate; + } debugfs; + + /* + * There are multiple sources in the EMC driver which could request + * a min/max clock rate, these rates are contained in this array. + */ + struct emc_rate_request requested_rate[EMC_RATE_TYPE_MAX]; + + /* protect shared rate-change code path */ + struct mutex rate_lock; + + bool mrr_error; +}; + +static int emc_seq_update_timing(struct tegra_emc *emc) +{ + u32 val; + int err; + + writel_relaxed(EMC_TIMING_UPDATE, emc->regs + EMC_TIMING_CONTROL); + + err = readl_relaxed_poll_timeout_atomic(emc->regs + EMC_STATUS, val, + !(val & EMC_STATUS_TIMING_UPDATE_STALLED), + 1, 200); + if (err) { + dev_err(emc->dev, "failed to update timing: %d\n", err); + return err; + } + + return 0; +} + +static irqreturn_t tegra_emc_isr(int irq, void *data) +{ + struct tegra_emc *emc = data; + u32 intmask = EMC_REFRESH_OVERFLOW_INT; + u32 status; + + status = readl_relaxed(emc->regs + EMC_INTSTATUS) & intmask; + if (!status) + return IRQ_NONE; + + /* notify about HW problem */ + if (status & EMC_REFRESH_OVERFLOW_INT) + dev_err_ratelimited(emc->dev, + "refresh request overflow timeout\n"); + + /* clear interrupts */ + writel_relaxed(status, emc->regs + EMC_INTSTATUS); + + return IRQ_HANDLED; +} + +static struct emc_timing *emc_find_timing(struct tegra_emc *emc, + unsigned long rate) +{ + struct emc_timing *timing = NULL; + unsigned int i; + + for (i = 0; i < emc->num_timings; i++) { + if (emc->timings[i].rate >= rate) { + timing = &emc->timings[i]; + break; + } + } + + if (!timing) { + dev_err(emc->dev, "no timing for rate %lu\n", rate); + return NULL; + } + + return timing; +} + +static bool emc_dqs_preset(struct tegra_emc *emc, struct emc_timing *timing, + bool *schmitt_to_vref) +{ + bool preset = false; + u32 val; + + if (timing->data[71] & EMC_XM2DQSPADCTRL2_VREF_ENABLE) { + val = readl_relaxed(emc->regs + EMC_XM2DQSPADCTRL2); + + if (!(val & EMC_XM2DQSPADCTRL2_VREF_ENABLE)) { + val |= EMC_XM2DQSPADCTRL2_VREF_ENABLE; + writel_relaxed(val, emc->regs + EMC_XM2DQSPADCTRL2); + + preset = true; + } + } + + if (timing->data[78] & EMC_XM2DQSPADCTRL3_VREF_ENABLE) { + val = readl_relaxed(emc->regs + EMC_XM2DQSPADCTRL3); + + if (!(val & EMC_XM2DQSPADCTRL3_VREF_ENABLE)) { + val |= EMC_XM2DQSPADCTRL3_VREF_ENABLE; + writel_relaxed(val, emc->regs + EMC_XM2DQSPADCTRL3); + + preset = true; + } + } + + if (timing->data[77] & EMC_XM2QUSEPADCTRL_IVREF_ENABLE) { + val = readl_relaxed(emc->regs + EMC_XM2QUSEPADCTRL); + + if (!(val & EMC_XM2QUSEPADCTRL_IVREF_ENABLE)) { + val |= EMC_XM2QUSEPADCTRL_IVREF_ENABLE; + writel_relaxed(val, emc->regs + EMC_XM2QUSEPADCTRL); + + *schmitt_to_vref = true; + preset = true; + } + } + + return preset; +} + +static int emc_prepare_mc_clk_cfg(struct tegra_emc *emc, unsigned long rate) +{ + struct tegra_mc *mc = emc->mc; + unsigned int misc0_index = 16; + unsigned int i; + bool same; + + for (i = 0; i < mc->num_timings; i++) { + if (mc->timings[i].rate != rate) + continue; + + if (mc->timings[i].emem_data[misc0_index] & BIT(27)) + same = true; + else + same = false; + + return tegra20_clk_prepare_emc_mc_same_freq(emc->clk, same); + } + + return -EINVAL; +} + +static int emc_prepare_timing_change(struct tegra_emc *emc, unsigned long rate) +{ + struct emc_timing *timing = emc_find_timing(emc, rate); + enum emc_dll_change dll_change; + enum emc_dram_type dram_type; + bool schmitt_to_vref = false; + unsigned int pre_wait = 0; + bool qrst_used = false; + unsigned int dram_num; + unsigned int i; + u32 fbio_cfg5; + u32 emc_dbg; + u32 val; + int err; + + if (!timing || emc->bad_state) + return -EINVAL; + + dev_dbg(emc->dev, "%s: using timing rate %lu for requested rate %lu\n", + __func__, timing->rate, rate); + + emc->bad_state = true; + + err = emc_prepare_mc_clk_cfg(emc, rate); + if (err) { + dev_err(emc->dev, "mc clock preparation failed: %d\n", err); + return err; + } + + emc->vref_cal_toggle = false; + emc->mc_override = mc_readl(emc->mc, MC_EMEM_ARB_OVERRIDE); + emc->emc_cfg = readl_relaxed(emc->regs + EMC_CFG); + emc_dbg = readl_relaxed(emc->regs + EMC_DBG); + + if (emc->dll_on == !!(timing->emc_mode_1 & 0x1)) + dll_change = DLL_CHANGE_NONE; + else if (timing->emc_mode_1 & 0x1) + dll_change = DLL_CHANGE_ON; + else + dll_change = DLL_CHANGE_OFF; + + emc->dll_on = !!(timing->emc_mode_1 & 0x1); + + if (timing->data[80] && !readl_relaxed(emc->regs + EMC_ZCAL_INTERVAL)) + emc->zcal_long = true; + else + emc->zcal_long = false; + + fbio_cfg5 = readl_relaxed(emc->regs + EMC_FBIO_CFG5); + dram_type = fbio_cfg5 & EMC_FBIO_CFG5_DRAM_TYPE_MASK; + + dram_num = tegra_mc_get_emem_device_count(emc->mc); + + /* disable dynamic self-refresh */ + if (emc->emc_cfg & EMC_CFG_DYN_SREF_ENABLE) { + emc->emc_cfg &= ~EMC_CFG_DYN_SREF_ENABLE; + writel_relaxed(emc->emc_cfg, emc->regs + EMC_CFG); + + pre_wait = 5; + } + + /* update MC arbiter settings */ + val = mc_readl(emc->mc, MC_EMEM_ARB_OUTSTANDING_REQ); + if (!(val & MC_EMEM_ARB_OUTSTANDING_REQ_HOLDOFF_OVERRIDE) || + ((val & MC_EMEM_ARB_OUTSTANDING_REQ_MAX_MASK) > 0x50)) { + + val = MC_EMEM_ARB_OUTSTANDING_REQ_LIMIT_ENABLE | + MC_EMEM_ARB_OUTSTANDING_REQ_HOLDOFF_OVERRIDE | 0x50; + mc_writel(emc->mc, val, MC_EMEM_ARB_OUTSTANDING_REQ); + mc_writel(emc->mc, MC_TIMING_UPDATE, MC_TIMING_CONTROL); + } + + if (emc->mc_override & MC_EMEM_ARB_OVERRIDE_EACK_MASK) + mc_writel(emc->mc, + emc->mc_override & ~MC_EMEM_ARB_OVERRIDE_EACK_MASK, + MC_EMEM_ARB_OVERRIDE); + + /* check DQ/DQS VREF delay */ + if (emc_dqs_preset(emc, timing, &schmitt_to_vref)) { + if (pre_wait < 3) + pre_wait = 3; + } + + if (pre_wait) { + err = emc_seq_update_timing(emc); + if (err) + return err; + + udelay(pre_wait); + } + + /* disable auto-calibration if VREF mode is switching */ + if (timing->emc_auto_cal_interval) { + val = readl_relaxed(emc->regs + EMC_XM2COMPPADCTRL); + val ^= timing->data[74]; + + if (val & EMC_XM2COMPPADCTRL_VREF_CAL_ENABLE) { + writel_relaxed(0, emc->regs + EMC_AUTO_CAL_INTERVAL); + + err = readl_relaxed_poll_timeout_atomic( + emc->regs + EMC_AUTO_CAL_STATUS, val, + !(val & EMC_AUTO_CAL_STATUS_ACTIVE), 1, 300); + if (err) { + dev_err(emc->dev, + "auto-cal finish timeout: %d\n", err); + return err; + } + + emc->vref_cal_toggle = true; + } + } + + /* program shadow registers */ + for (i = 0; i < ARRAY_SIZE(timing->data); i++) { + /* EMC_XM2CLKPADCTRL should be programmed separately */ + if (i != 73) + writel_relaxed(timing->data[i], + emc->regs + emc_timing_registers[i]); + } + + err = tegra_mc_write_emem_configuration(emc->mc, timing->rate); + if (err) + return err; + + /* DDR3: predict MRS long wait count */ + if (dram_type == DRAM_TYPE_DDR3 && dll_change == DLL_CHANGE_ON) { + u32 cnt = 512; + + if (emc->zcal_long) + cnt -= dram_num * 256; + + val = timing->data[82] & EMC_MRS_WAIT_CNT_SHORT_WAIT_MASK; + if (cnt < val) + cnt = val; + + val = timing->data[82] & ~EMC_MRS_WAIT_CNT_LONG_WAIT_MASK; + val |= (cnt << EMC_MRS_WAIT_CNT_LONG_WAIT_SHIFT) & + EMC_MRS_WAIT_CNT_LONG_WAIT_MASK; + + writel_relaxed(val, emc->regs + EMC_MRS_WAIT_CNT); + } + + /* this read also completes the writes */ + val = readl_relaxed(emc->regs + EMC_SEL_DPD_CTRL); + + if (!(val & EMC_SEL_DPD_CTRL_QUSE_DPD_ENABLE) && schmitt_to_vref) { + u32 cur_mode, new_mode; + + cur_mode = fbio_cfg5 & EMC_CFG5_QUSE_MODE_MASK; + cur_mode >>= EMC_CFG5_QUSE_MODE_SHIFT; + + new_mode = timing->data[39] & EMC_CFG5_QUSE_MODE_MASK; + new_mode >>= EMC_CFG5_QUSE_MODE_SHIFT; + + if ((cur_mode != EMC_CFG5_QUSE_MODE_PULSE_INTERN && + cur_mode != EMC_CFG5_QUSE_MODE_INTERNAL_LPBK) || + (new_mode != EMC_CFG5_QUSE_MODE_PULSE_INTERN && + new_mode != EMC_CFG5_QUSE_MODE_INTERNAL_LPBK)) + qrst_used = true; + } + + /* flow control marker 1 */ + writel_relaxed(0x1, emc->regs + EMC_STALL_THEN_EXE_BEFORE_CLKCHANGE); + + /* enable periodic reset */ + if (qrst_used) { + writel_relaxed(emc_dbg | EMC_DBG_WRITE_MUX_ACTIVE, + emc->regs + EMC_DBG); + writel_relaxed(emc->emc_cfg | EMC_CFG_PERIODIC_QRST, + emc->regs + EMC_CFG); + writel_relaxed(emc_dbg, emc->regs + EMC_DBG); + } + + /* disable auto-refresh to save time after clock change */ + writel_relaxed(EMC_REFCTRL_DISABLE_ALL(dram_num), + emc->regs + EMC_REFCTRL); + + /* turn off DLL and enter self-refresh on DDR3 */ + if (dram_type == DRAM_TYPE_DDR3) { + if (dll_change == DLL_CHANGE_OFF) + writel_relaxed(timing->emc_mode_1, + emc->regs + EMC_EMRS); + + writel_relaxed(DRAM_BROADCAST(dram_num) | + EMC_SELF_REF_CMD_ENABLED, + emc->regs + EMC_SELF_REF); + } + + /* flow control marker 2 */ + writel_relaxed(0x1, emc->regs + EMC_STALL_THEN_EXE_AFTER_CLKCHANGE); + + /* enable write-active MUX, update unshadowed pad control */ + writel_relaxed(emc_dbg | EMC_DBG_WRITE_MUX_ACTIVE, emc->regs + EMC_DBG); + writel_relaxed(timing->data[73], emc->regs + EMC_XM2CLKPADCTRL); + + /* restore periodic QRST and disable write-active MUX */ + val = !!(emc->emc_cfg & EMC_CFG_PERIODIC_QRST); + if (qrst_used || timing->emc_cfg_periodic_qrst != val) { + if (timing->emc_cfg_periodic_qrst) + emc->emc_cfg |= EMC_CFG_PERIODIC_QRST; + else + emc->emc_cfg &= ~EMC_CFG_PERIODIC_QRST; + + writel_relaxed(emc->emc_cfg, emc->regs + EMC_CFG); + } + writel_relaxed(emc_dbg, emc->regs + EMC_DBG); + + /* exit self-refresh on DDR3 */ + if (dram_type == DRAM_TYPE_DDR3) + writel_relaxed(DRAM_BROADCAST(dram_num), + emc->regs + EMC_SELF_REF); + + /* set DRAM-mode registers */ + if (dram_type == DRAM_TYPE_DDR3) { + if (timing->emc_mode_1 != emc->emc_mode_1) + writel_relaxed(timing->emc_mode_1, + emc->regs + EMC_EMRS); + + if (timing->emc_mode_2 != emc->emc_mode_2) + writel_relaxed(timing->emc_mode_2, + emc->regs + EMC_EMRS); + + if (timing->emc_mode_reset != emc->emc_mode_reset || + dll_change == DLL_CHANGE_ON) { + val = timing->emc_mode_reset; + if (dll_change == DLL_CHANGE_ON) { + val |= EMC_MODE_SET_DLL_RESET; + val |= EMC_MODE_SET_LONG_CNT; + } else { + val &= ~EMC_MODE_SET_DLL_RESET; + } + writel_relaxed(val, emc->regs + EMC_MRS); + } + } else { + if (timing->emc_mode_2 != emc->emc_mode_2) + writel_relaxed(timing->emc_mode_2, + emc->regs + EMC_MRW); + + if (timing->emc_mode_1 != emc->emc_mode_1) + writel_relaxed(timing->emc_mode_1, + emc->regs + EMC_MRW); + } + + emc->emc_mode_1 = timing->emc_mode_1; + emc->emc_mode_2 = timing->emc_mode_2; + emc->emc_mode_reset = timing->emc_mode_reset; + + /* issue ZCAL command if turning ZCAL on */ + if (emc->zcal_long) { + writel_relaxed(EMC_ZQ_CAL_LONG_CMD_DEV0, + emc->regs + EMC_ZQ_CAL); + + if (dram_num > 1) + writel_relaxed(EMC_ZQ_CAL_LONG_CMD_DEV1, + emc->regs + EMC_ZQ_CAL); + } + + /* flow control marker 3 */ + writel_relaxed(0x1, emc->regs + EMC_UNSTALL_RW_AFTER_CLKCHANGE); + + /* + * Read and discard an arbitrary MC register (Note: EMC registers + * can't be used) to ensure the register writes are completed. + */ + mc_readl(emc->mc, MC_EMEM_ARB_OVERRIDE); + + return 0; +} + +static int emc_complete_timing_change(struct tegra_emc *emc, + unsigned long rate) +{ + struct emc_timing *timing = emc_find_timing(emc, rate); + unsigned int dram_num; + int err; + u32 v; + + err = readl_relaxed_poll_timeout_atomic(emc->regs + EMC_INTSTATUS, v, + v & EMC_CLKCHANGE_COMPLETE_INT, + 1, 100); + if (err) { + dev_err(emc->dev, "emc-car handshake timeout: %d\n", err); + return err; + } + + /* re-enable auto-refresh */ + dram_num = tegra_mc_get_emem_device_count(emc->mc); + writel_relaxed(EMC_REFCTRL_ENABLE_ALL(dram_num), + emc->regs + EMC_REFCTRL); + + /* restore auto-calibration */ + if (emc->vref_cal_toggle) + writel_relaxed(timing->emc_auto_cal_interval, + emc->regs + EMC_AUTO_CAL_INTERVAL); + + /* restore dynamic self-refresh */ + if (timing->emc_cfg_dyn_self_ref) { + emc->emc_cfg |= EMC_CFG_DYN_SREF_ENABLE; + writel_relaxed(emc->emc_cfg, emc->regs + EMC_CFG); + } + + /* set number of clocks to wait after each ZQ command */ + if (emc->zcal_long) + writel_relaxed(timing->emc_zcal_cnt_long, + emc->regs + EMC_ZCAL_WAIT_CNT); + + /* wait for writes to settle */ + udelay(2); + + /* update restored timing */ + err = emc_seq_update_timing(emc); + if (!err) + emc->bad_state = false; + + /* restore early ACK */ + mc_writel(emc->mc, emc->mc_override, MC_EMEM_ARB_OVERRIDE); + + return err; +} + +static int emc_unprepare_timing_change(struct tegra_emc *emc, + unsigned long rate) +{ + if (!emc->bad_state) { + /* shouldn't ever happen in practice */ + dev_err(emc->dev, "timing configuration can't be reverted\n"); + emc->bad_state = true; + } + + return 0; +} + +static int emc_clk_change_notify(struct notifier_block *nb, + unsigned long msg, void *data) +{ + struct tegra_emc *emc = container_of(nb, struct tegra_emc, clk_nb); + struct clk_notifier_data *cnd = data; + int err; + + switch (msg) { + case PRE_RATE_CHANGE: + /* + * Disable interrupt since read accesses are prohibited after + * stalling. + */ + disable_irq(emc->irq); + err = emc_prepare_timing_change(emc, cnd->new_rate); + enable_irq(emc->irq); + break; + + case ABORT_RATE_CHANGE: + err = emc_unprepare_timing_change(emc, cnd->old_rate); + break; + + case POST_RATE_CHANGE: + err = emc_complete_timing_change(emc, cnd->new_rate); + break; + + default: + return NOTIFY_DONE; + } + + return notifier_from_errno(err); +} + +static int load_one_timing_from_dt(struct tegra_emc *emc, + struct emc_timing *timing, + struct device_node *node) +{ + u32 value; + int err; + + err = of_property_read_u32(node, "clock-frequency", &value); + if (err) { + dev_err(emc->dev, "timing %pOF: failed to read rate: %d\n", + node, err); + return err; + } + + timing->rate = value; + + err = of_property_read_u32_array(node, "nvidia,emc-configuration", + timing->data, + ARRAY_SIZE(emc_timing_registers)); + if (err) { + dev_err(emc->dev, + "timing %pOF: failed to read emc timing data: %d\n", + node, err); + return err; + } + +#define EMC_READ_BOOL(prop, dtprop) \ + timing->prop = of_property_read_bool(node, dtprop); + +#define EMC_READ_U32(prop, dtprop) \ + err = of_property_read_u32(node, dtprop, &timing->prop); \ + if (err) { \ + dev_err(emc->dev, \ + "timing %pOFn: failed to read " #prop ": %d\n", \ + node, err); \ + return err; \ + } + + EMC_READ_U32(emc_auto_cal_interval, "nvidia,emc-auto-cal-interval") + EMC_READ_U32(emc_mode_1, "nvidia,emc-mode-1") + EMC_READ_U32(emc_mode_2, "nvidia,emc-mode-2") + EMC_READ_U32(emc_mode_reset, "nvidia,emc-mode-reset") + EMC_READ_U32(emc_zcal_cnt_long, "nvidia,emc-zcal-cnt-long") + EMC_READ_BOOL(emc_cfg_dyn_self_ref, "nvidia,emc-cfg-dyn-self-ref") + EMC_READ_BOOL(emc_cfg_periodic_qrst, "nvidia,emc-cfg-periodic-qrst") + +#undef EMC_READ_U32 +#undef EMC_READ_BOOL + + dev_dbg(emc->dev, "%s: %pOF: rate %lu\n", __func__, node, timing->rate); + + return 0; +} + +static int cmp_timings(const void *_a, const void *_b) +{ + const struct emc_timing *a = _a; + const struct emc_timing *b = _b; + + if (a->rate < b->rate) + return -1; + + if (a->rate > b->rate) + return 1; + + return 0; +} + +static int emc_check_mc_timings(struct tegra_emc *emc) +{ + struct tegra_mc *mc = emc->mc; + unsigned int i; + + if (emc->num_timings != mc->num_timings) { + dev_err(emc->dev, "emc/mc timings number mismatch: %u %u\n", + emc->num_timings, mc->num_timings); + return -EINVAL; + } + + for (i = 0; i < mc->num_timings; i++) { + if (emc->timings[i].rate != mc->timings[i].rate) { + dev_err(emc->dev, + "emc/mc timing rate mismatch: %lu %lu\n", + emc->timings[i].rate, mc->timings[i].rate); + return -EINVAL; + } + } + + return 0; +} + +static int emc_load_timings_from_dt(struct tegra_emc *emc, + struct device_node *node) +{ + struct device_node *child; + struct emc_timing *timing; + int child_count; + int err; + + child_count = of_get_child_count(node); + if (!child_count) { + dev_err(emc->dev, "no memory timings in: %pOF\n", node); + return -EINVAL; + } + + emc->timings = devm_kcalloc(emc->dev, child_count, sizeof(*timing), + GFP_KERNEL); + if (!emc->timings) + return -ENOMEM; + + emc->num_timings = child_count; + timing = emc->timings; + + for_each_child_of_node(node, child) { + err = load_one_timing_from_dt(emc, timing++, child); + if (err) { + of_node_put(child); + return err; + } + } + + sort(emc->timings, emc->num_timings, sizeof(*timing), cmp_timings, + NULL); + + err = emc_check_mc_timings(emc); + if (err) + return err; + + dev_info_once(emc->dev, + "got %u timings for RAM code %u (min %luMHz max %luMHz)\n", + emc->num_timings, + tegra_read_ram_code(), + emc->timings[0].rate / 1000000, + emc->timings[emc->num_timings - 1].rate / 1000000); + + return 0; +} + +static struct device_node *emc_find_node_by_ram_code(struct tegra_emc *emc) +{ + struct device *dev = emc->dev; + struct device_node *np; + u32 value, ram_code; + int err; + + if (emc->mrr_error) { + dev_warn(dev, "memory timings skipped due to MRR error\n"); + return NULL; + } + + if (of_get_child_count(dev->of_node) == 0) { + dev_info_once(dev, "device-tree doesn't have memory timings\n"); + return NULL; + } + + ram_code = tegra_read_ram_code(); + + for_each_child_of_node(dev->of_node, np) { + err = of_property_read_u32(np, "nvidia,ram-code", &value); + if (err || value != ram_code) + continue; + + return np; + } + + dev_err(dev, "no memory timings for RAM code %u found in device-tree\n", + ram_code); + + return NULL; +} + +static int emc_read_lpddr_mode_register(struct tegra_emc *emc, + unsigned int emem_dev, + unsigned int register_addr, + unsigned int *register_data) +{ + u32 memory_dev = emem_dev ? 1 : 2; + u32 val, mr_mask = 0xff; + int err; + + /* clear data-valid interrupt status */ + writel_relaxed(EMC_MRR_DIVLD_INT, emc->regs + EMC_INTSTATUS); + + /* issue mode register read request */ + val = FIELD_PREP(EMC_MRR_DEV_SELECTN, memory_dev); + val |= FIELD_PREP(EMC_MRR_MRR_MA, register_addr); + + writel_relaxed(val, emc->regs + EMC_MRR); + + /* wait for the LPDDR2 data-valid interrupt */ + err = readl_relaxed_poll_timeout_atomic(emc->regs + EMC_INTSTATUS, val, + val & EMC_MRR_DIVLD_INT, + 1, 100); + if (err) { + dev_err(emc->dev, "mode register %u read failed: %d\n", + register_addr, err); + emc->mrr_error = true; + return err; + } + + /* read out mode register data */ + val = readl_relaxed(emc->regs + EMC_MRR); + *register_data = FIELD_GET(EMC_MRR_MRR_DATA, val) & mr_mask; + + return 0; +} + +static void emc_read_lpddr_sdram_info(struct tegra_emc *emc, + unsigned int emem_dev) +{ + union lpddr2_basic_config4 basic_conf4; + unsigned int manufacturer_id; + unsigned int revision_id1; + unsigned int revision_id2; + + /* these registers are standard for all LPDDR JEDEC memory chips */ + emc_read_lpddr_mode_register(emc, emem_dev, 5, &manufacturer_id); + emc_read_lpddr_mode_register(emc, emem_dev, 6, &revision_id1); + emc_read_lpddr_mode_register(emc, emem_dev, 7, &revision_id2); + emc_read_lpddr_mode_register(emc, emem_dev, 8, &basic_conf4.value); + + dev_info(emc->dev, "SDRAM[dev%u]: manufacturer: 0x%x (%s) rev1: 0x%x rev2: 0x%x prefetch: S%u density: %uMbit iowidth: %ubit\n", + emem_dev, manufacturer_id, + lpddr2_jedec_manufacturer(manufacturer_id), + revision_id1, revision_id2, + 4 >> basic_conf4.arch_type, + 64 << basic_conf4.density, + 32 >> basic_conf4.io_width); +} + +static int emc_setup_hw(struct tegra_emc *emc) +{ + u32 fbio_cfg5, emc_cfg, emc_dbg, emc_adr_cfg; + u32 intmask = EMC_REFRESH_OVERFLOW_INT; + static bool print_sdram_info_once; + enum emc_dram_type dram_type; + const char *dram_type_str; + unsigned int emem_numdev; + + fbio_cfg5 = readl_relaxed(emc->regs + EMC_FBIO_CFG5); + dram_type = fbio_cfg5 & EMC_FBIO_CFG5_DRAM_TYPE_MASK; + + emc_cfg = readl_relaxed(emc->regs + EMC_CFG_2); + + /* enable EMC and CAR to handshake on PLL divider/source changes */ + emc_cfg |= EMC_CLKCHANGE_REQ_ENABLE; + + /* configure clock change mode accordingly to DRAM type */ + switch (dram_type) { + case DRAM_TYPE_LPDDR2: + emc_cfg |= EMC_CLKCHANGE_PD_ENABLE; + emc_cfg &= ~EMC_CLKCHANGE_SR_ENABLE; + break; + + default: + emc_cfg &= ~EMC_CLKCHANGE_SR_ENABLE; + emc_cfg &= ~EMC_CLKCHANGE_PD_ENABLE; + break; + } + + writel_relaxed(emc_cfg, emc->regs + EMC_CFG_2); + + /* initialize interrupt */ + writel_relaxed(intmask, emc->regs + EMC_INTMASK); + writel_relaxed(0xffffffff, emc->regs + EMC_INTSTATUS); + + /* ensure that unwanted debug features are disabled */ + emc_dbg = readl_relaxed(emc->regs + EMC_DBG); + emc_dbg |= EMC_DBG_CFG_PRIORITY; + emc_dbg &= ~EMC_DBG_READ_MUX_ASSEMBLY; + emc_dbg &= ~EMC_DBG_WRITE_MUX_ACTIVE; + emc_dbg &= ~EMC_DBG_FORCE_UPDATE; + writel_relaxed(emc_dbg, emc->regs + EMC_DBG); + + switch (dram_type) { + case DRAM_TYPE_DDR1: + dram_type_str = "DDR1"; + break; + case DRAM_TYPE_LPDDR2: + dram_type_str = "LPDDR2"; + break; + case DRAM_TYPE_DDR2: + dram_type_str = "DDR2"; + break; + case DRAM_TYPE_DDR3: + dram_type_str = "DDR3"; + break; + } + + emc_adr_cfg = readl_relaxed(emc->regs + EMC_ADR_CFG); + emem_numdev = FIELD_GET(EMC_ADR_CFG_EMEM_NUMDEV, emc_adr_cfg) + 1; + + dev_info_once(emc->dev, "%u %s %s attached\n", emem_numdev, + dram_type_str, emem_numdev == 2 ? "devices" : "device"); + + if (dram_type == DRAM_TYPE_LPDDR2 && !print_sdram_info_once) { + while (emem_numdev--) + emc_read_lpddr_sdram_info(emc, emem_numdev); + + print_sdram_info_once = true; + } + + return 0; +} + +static long emc_round_rate(unsigned long rate, + unsigned long min_rate, + unsigned long max_rate, + void *arg) +{ + struct emc_timing *timing = NULL; + struct tegra_emc *emc = arg; + unsigned int i; + + if (!emc->num_timings) + return clk_get_rate(emc->clk); + + min_rate = min(min_rate, emc->timings[emc->num_timings - 1].rate); + + for (i = 0; i < emc->num_timings; i++) { + if (emc->timings[i].rate < rate && i != emc->num_timings - 1) + continue; + + if (emc->timings[i].rate > max_rate) { + i = max(i, 1u) - 1; + + if (emc->timings[i].rate < min_rate) + break; + } + + if (emc->timings[i].rate < min_rate) + continue; + + timing = &emc->timings[i]; + break; + } + + if (!timing) { + dev_err(emc->dev, "no timing for rate %lu min %lu max %lu\n", + rate, min_rate, max_rate); + return -EINVAL; + } + + return timing->rate; +} + +static void tegra_emc_rate_requests_init(struct tegra_emc *emc) +{ + unsigned int i; + + for (i = 0; i < EMC_RATE_TYPE_MAX; i++) { + emc->requested_rate[i].min_rate = 0; + emc->requested_rate[i].max_rate = ULONG_MAX; + } +} + +static int emc_request_rate(struct tegra_emc *emc, + unsigned long new_min_rate, + unsigned long new_max_rate, + enum emc_rate_request_type type) +{ + struct emc_rate_request *req = emc->requested_rate; + unsigned long min_rate = 0, max_rate = ULONG_MAX; + unsigned int i; + int err; + + /* select minimum and maximum rates among the requested rates */ + for (i = 0; i < EMC_RATE_TYPE_MAX; i++, req++) { + if (i == type) { + min_rate = max(new_min_rate, min_rate); + max_rate = min(new_max_rate, max_rate); + } else { + min_rate = max(req->min_rate, min_rate); + max_rate = min(req->max_rate, max_rate); + } + } + + if (min_rate > max_rate) { + dev_err_ratelimited(emc->dev, "%s: type %u: out of range: %lu %lu\n", + __func__, type, min_rate, max_rate); + return -ERANGE; + } + + /* + * EMC rate-changes should go via OPP API because it manages voltage + * changes. + */ + err = dev_pm_opp_set_rate(emc->dev, min_rate); + if (err) + return err; + + emc->requested_rate[type].min_rate = new_min_rate; + emc->requested_rate[type].max_rate = new_max_rate; + + return 0; +} + +static int emc_set_min_rate(struct tegra_emc *emc, unsigned long rate, + enum emc_rate_request_type type) +{ + struct emc_rate_request *req = &emc->requested_rate[type]; + int ret; + + mutex_lock(&emc->rate_lock); + ret = emc_request_rate(emc, rate, req->max_rate, type); + mutex_unlock(&emc->rate_lock); + + return ret; +} + +static int emc_set_max_rate(struct tegra_emc *emc, unsigned long rate, + enum emc_rate_request_type type) +{ + struct emc_rate_request *req = &emc->requested_rate[type]; + int ret; + + mutex_lock(&emc->rate_lock); + ret = emc_request_rate(emc, req->min_rate, rate, type); + mutex_unlock(&emc->rate_lock); + + return ret; +} + +/* + * debugfs interface + * + * The memory controller driver exposes some files in debugfs that can be used + * to control the EMC frequency. The top-level directory can be found here: + * + * /sys/kernel/debug/emc + * + * It contains the following files: + * + * - available_rates: This file contains a list of valid, space-separated + * EMC frequencies. + * + * - min_rate: Writing a value to this file sets the given frequency as the + * floor of the permitted range. If this is higher than the currently + * configured EMC frequency, this will cause the frequency to be + * increased so that it stays within the valid range. + * + * - max_rate: Similarily to the min_rate file, writing a value to this file + * sets the given frequency as the ceiling of the permitted range. If + * the value is lower than the currently configured EMC frequency, this + * will cause the frequency to be decreased so that it stays within the + * valid range. + */ + +static bool tegra_emc_validate_rate(struct tegra_emc *emc, unsigned long rate) +{ + unsigned int i; + + for (i = 0; i < emc->num_timings; i++) + if (rate == emc->timings[i].rate) + return true; + + return false; +} + +static int tegra_emc_debug_available_rates_show(struct seq_file *s, void *data) +{ + struct tegra_emc *emc = s->private; + const char *prefix = ""; + unsigned int i; + + for (i = 0; i < emc->num_timings; i++) { + seq_printf(s, "%s%lu", prefix, emc->timings[i].rate); + prefix = " "; + } + + seq_puts(s, "\n"); + + return 0; +} + +static int tegra_emc_debug_available_rates_open(struct inode *inode, + struct file *file) +{ + return single_open(file, tegra_emc_debug_available_rates_show, + inode->i_private); +} + +static const struct file_operations tegra_emc_debug_available_rates_fops = { + .open = tegra_emc_debug_available_rates_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static int tegra_emc_debug_min_rate_get(void *data, u64 *rate) +{ + struct tegra_emc *emc = data; + + *rate = emc->debugfs.min_rate; + + return 0; +} + +static int tegra_emc_debug_min_rate_set(void *data, u64 rate) +{ + struct tegra_emc *emc = data; + int err; + + if (!tegra_emc_validate_rate(emc, rate)) + return -EINVAL; + + err = emc_set_min_rate(emc, rate, EMC_RATE_DEBUG); + if (err < 0) + return err; + + emc->debugfs.min_rate = rate; + + return 0; +} + +DEFINE_DEBUGFS_ATTRIBUTE(tegra_emc_debug_min_rate_fops, + tegra_emc_debug_min_rate_get, + tegra_emc_debug_min_rate_set, "%llu\n"); + +static int tegra_emc_debug_max_rate_get(void *data, u64 *rate) +{ + struct tegra_emc *emc = data; + + *rate = emc->debugfs.max_rate; + + return 0; +} + +static int tegra_emc_debug_max_rate_set(void *data, u64 rate) +{ + struct tegra_emc *emc = data; + int err; + + if (!tegra_emc_validate_rate(emc, rate)) + return -EINVAL; + + err = emc_set_max_rate(emc, rate, EMC_RATE_DEBUG); + if (err < 0) + return err; + + emc->debugfs.max_rate = rate; + + return 0; +} + +DEFINE_DEBUGFS_ATTRIBUTE(tegra_emc_debug_max_rate_fops, + tegra_emc_debug_max_rate_get, + tegra_emc_debug_max_rate_set, "%llu\n"); + +static void tegra_emc_debugfs_init(struct tegra_emc *emc) +{ + struct device *dev = emc->dev; + unsigned int i; + int err; + + emc->debugfs.min_rate = ULONG_MAX; + emc->debugfs.max_rate = 0; + + for (i = 0; i < emc->num_timings; i++) { + if (emc->timings[i].rate < emc->debugfs.min_rate) + emc->debugfs.min_rate = emc->timings[i].rate; + + if (emc->timings[i].rate > emc->debugfs.max_rate) + emc->debugfs.max_rate = emc->timings[i].rate; + } + + if (!emc->num_timings) { + emc->debugfs.min_rate = clk_get_rate(emc->clk); + emc->debugfs.max_rate = emc->debugfs.min_rate; + } + + err = clk_set_rate_range(emc->clk, emc->debugfs.min_rate, + emc->debugfs.max_rate); + if (err < 0) { + dev_err(dev, "failed to set rate range [%lu-%lu] for %pC\n", + emc->debugfs.min_rate, emc->debugfs.max_rate, + emc->clk); + } + + emc->debugfs.root = debugfs_create_dir("emc", NULL); + + debugfs_create_file("available_rates", 0444, emc->debugfs.root, + emc, &tegra_emc_debug_available_rates_fops); + debugfs_create_file("min_rate", 0644, emc->debugfs.root, + emc, &tegra_emc_debug_min_rate_fops); + debugfs_create_file("max_rate", 0644, emc->debugfs.root, + emc, &tegra_emc_debug_max_rate_fops); +} + +static inline struct tegra_emc * +to_tegra_emc_provider(struct icc_provider *provider) +{ + return container_of(provider, struct tegra_emc, provider); +} + +static struct icc_node_data * +emc_of_icc_xlate_extended(struct of_phandle_args *spec, void *data) +{ + struct icc_provider *provider = data; + struct icc_node_data *ndata; + struct icc_node *node; + + /* External Memory is the only possible ICC route */ + list_for_each_entry(node, &provider->nodes, node_list) { + if (node->id != TEGRA_ICC_EMEM) + continue; + + ndata = kzalloc(sizeof(*ndata), GFP_KERNEL); + if (!ndata) + return ERR_PTR(-ENOMEM); + + /* + * SRC and DST nodes should have matching TAG in order to have + * it set by default for a requested path. + */ + ndata->tag = TEGRA_MC_ICC_TAG_ISO; + ndata->node = node; + + return ndata; + } + + return ERR_PTR(-EPROBE_DEFER); +} + +static int emc_icc_set(struct icc_node *src, struct icc_node *dst) +{ + struct tegra_emc *emc = to_tegra_emc_provider(dst->provider); + unsigned long long peak_bw = icc_units_to_bps(dst->peak_bw); + unsigned long long avg_bw = icc_units_to_bps(dst->avg_bw); + unsigned long long rate = max(avg_bw, peak_bw); + const unsigned int dram_data_bus_width_bytes = 4; + const unsigned int ddr = 2; + int err; + + /* + * Tegra30 EMC runs on a clock rate of SDRAM bus. This means that + * EMC clock rate is twice smaller than the peak data rate because + * data is sampled on both EMC clock edges. + */ + do_div(rate, ddr * dram_data_bus_width_bytes); + rate = min_t(u64, rate, U32_MAX); + + err = emc_set_min_rate(emc, rate, EMC_RATE_ICC); + if (err) + return err; + + return 0; +} + +static int tegra_emc_interconnect_init(struct tegra_emc *emc) +{ + const struct tegra_mc_soc *soc = emc->mc->soc; + struct icc_node *node; + int err; + + emc->provider.dev = emc->dev; + emc->provider.set = emc_icc_set; + emc->provider.data = &emc->provider; + emc->provider.aggregate = soc->icc_ops->aggregate; + emc->provider.xlate_extended = emc_of_icc_xlate_extended; + + icc_provider_init(&emc->provider); + + /* create External Memory Controller node */ + node = icc_node_create(TEGRA_ICC_EMC); + if (IS_ERR(node)) { + err = PTR_ERR(node); + goto err_msg; + } + + node->name = "External Memory Controller"; + icc_node_add(node, &emc->provider); + + /* link External Memory Controller to External Memory (DRAM) */ + err = icc_link_create(node, TEGRA_ICC_EMEM); + if (err) + goto remove_nodes; + + /* create External Memory node */ + node = icc_node_create(TEGRA_ICC_EMEM); + if (IS_ERR(node)) { + err = PTR_ERR(node); + goto remove_nodes; + } + + node->name = "External Memory (DRAM)"; + icc_node_add(node, &emc->provider); + + err = icc_provider_register(&emc->provider); + if (err) + goto remove_nodes; + + return 0; + +remove_nodes: + icc_nodes_remove(&emc->provider); +err_msg: + dev_err(emc->dev, "failed to initialize ICC: %d\n", err); + + return err; +} + +static void devm_tegra_emc_unset_callback(void *data) +{ + tegra20_clk_set_emc_round_callback(NULL, NULL); +} + +static void devm_tegra_emc_unreg_clk_notifier(void *data) +{ + struct tegra_emc *emc = data; + + clk_notifier_unregister(emc->clk, &emc->clk_nb); +} + +static int tegra_emc_init_clk(struct tegra_emc *emc) +{ + int err; + + tegra20_clk_set_emc_round_callback(emc_round_rate, emc); + + err = devm_add_action_or_reset(emc->dev, devm_tegra_emc_unset_callback, + NULL); + if (err) + return err; + + emc->clk = devm_clk_get(emc->dev, NULL); + if (IS_ERR(emc->clk)) { + dev_err(emc->dev, "failed to get EMC clock: %pe\n", emc->clk); + return PTR_ERR(emc->clk); + } + + err = clk_notifier_register(emc->clk, &emc->clk_nb); + if (err) { + dev_err(emc->dev, "failed to register clk notifier: %d\n", err); + return err; + } + + err = devm_add_action_or_reset(emc->dev, + devm_tegra_emc_unreg_clk_notifier, emc); + if (err) + return err; + + return 0; +} + +static int tegra_emc_probe(struct platform_device *pdev) +{ + struct tegra_core_opp_params opp_params = {}; + struct device_node *np; + struct tegra_emc *emc; + int err; + + emc = devm_kzalloc(&pdev->dev, sizeof(*emc), GFP_KERNEL); + if (!emc) + return -ENOMEM; + + emc->mc = devm_tegra_memory_controller_get(&pdev->dev); + if (IS_ERR(emc->mc)) + return PTR_ERR(emc->mc); + + mutex_init(&emc->rate_lock); + emc->clk_nb.notifier_call = emc_clk_change_notify; + emc->dev = &pdev->dev; + + emc->regs = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(emc->regs)) + return PTR_ERR(emc->regs); + + err = emc_setup_hw(emc); + if (err) + return err; + + np = emc_find_node_by_ram_code(emc); + if (np) { + err = emc_load_timings_from_dt(emc, np); + of_node_put(np); + if (err) + return err; + } + + err = platform_get_irq(pdev, 0); + if (err < 0) + return err; + + emc->irq = err; + + err = devm_request_irq(&pdev->dev, emc->irq, tegra_emc_isr, 0, + dev_name(&pdev->dev), emc); + if (err) { + dev_err(&pdev->dev, "failed to request irq: %d\n", err); + return err; + } + + err = tegra_emc_init_clk(emc); + if (err) + return err; + + opp_params.init_state = true; + + err = devm_tegra_core_dev_init_opp_table(&pdev->dev, &opp_params); + if (err) + return err; + + platform_set_drvdata(pdev, emc); + tegra_emc_rate_requests_init(emc); + tegra_emc_debugfs_init(emc); + tegra_emc_interconnect_init(emc); + + /* + * Don't allow the kernel module to be unloaded. Unloading adds some + * extra complexity which doesn't really worth the effort in a case of + * this driver. + */ + try_module_get(THIS_MODULE); + + return 0; +} + +static int tegra_emc_suspend(struct device *dev) +{ + struct tegra_emc *emc = dev_get_drvdata(dev); + int err; + + /* take exclusive control over the clock's rate */ + err = clk_rate_exclusive_get(emc->clk); + if (err) { + dev_err(emc->dev, "failed to acquire clk: %d\n", err); + return err; + } + + /* suspending in a bad state will hang machine */ + if (WARN(emc->bad_state, "hardware in a bad state\n")) + return -EINVAL; + + emc->bad_state = true; + + return 0; +} + +static int tegra_emc_resume(struct device *dev) +{ + struct tegra_emc *emc = dev_get_drvdata(dev); + + emc_setup_hw(emc); + emc->bad_state = false; + + clk_rate_exclusive_put(emc->clk); + + return 0; +} + +static const struct dev_pm_ops tegra_emc_pm_ops = { + .suspend = tegra_emc_suspend, + .resume = tegra_emc_resume, +}; + +static const struct of_device_id tegra_emc_of_match[] = { + { .compatible = "nvidia,tegra30-emc", }, + {}, +}; +MODULE_DEVICE_TABLE(of, tegra_emc_of_match); + +static struct platform_driver tegra_emc_driver = { + .probe = tegra_emc_probe, + .driver = { + .name = "tegra30-emc", + .of_match_table = tegra_emc_of_match, + .pm = &tegra_emc_pm_ops, + .suppress_bind_attrs = true, + .sync_state = icc_sync_state, + }, +}; +module_platform_driver(tegra_emc_driver); + +MODULE_AUTHOR("Dmitry Osipenko <digetx@gmail.com>"); +MODULE_DESCRIPTION("NVIDIA Tegra30 EMC driver"); +MODULE_LICENSE("GPL v2"); |