diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/memory/emif.c | 211 |
1 files changed, 209 insertions, 2 deletions
diff --git a/drivers/memory/emif.c b/drivers/memory/emif.c index bd116eb..a8dcf35 100644 --- a/drivers/memory/emif.c +++ b/drivers/memory/emif.c @@ -545,6 +545,42 @@ static u32 get_pwr_mgmt_ctrl(u32 freq, struct emif_data *emif, u32 ip_rev) } /* + * 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 */ @@ -627,6 +663,158 @@ out: 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; + + 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; + } + + 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"); + kernel_power_off(); + 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 get_default_timings(struct emif_data *emif) { struct emif_platform_data *pd = emif->plat_data; @@ -803,6 +991,7 @@ static int __init_or_module emif_probe(struct platform_device *pdev) { struct emif_data *emif; struct resource *res; + int irq; emif = get_device_details(pdev); if (!emif) { @@ -831,6 +1020,16 @@ static int __init_or_module emif_probe(struct platform_device *pdev) goto error; } + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + dev_err(emif->dev, "%s: error getting IRQ resource - %d\n", + __func__, irq); + goto error; + } + + disable_and_clear_all_interrupts(emif); + setup_interrupts(emif, irq); + /* One-time actions taken on probing the first device */ if (!emif1) { emif1 = emif; @@ -843,14 +1042,21 @@ static int __init_or_module emif_probe(struct platform_device *pdev) */ } - dev_info(&pdev->dev, "%s: device configured with addr = %p\n", - __func__, emif->base); + dev_info(&pdev->dev, "%s: device configured with addr = %p and IRQ%d\n", + __func__, emif->base, irq); return 0; error: return -ENODEV; } +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) { @@ -1154,6 +1360,7 @@ static void __attribute__((unused)) freq_post_notify_handling(void) } static struct platform_driver emif_driver = { + .shutdown = emif_shutdown, .driver = { .name = "emif", }, |
