1 files changed, 396 insertions, 0 deletions
diff --git a/drivers/gpu/drm/panthor/panthor_gpu.c b/drivers/gpu/drm/panthor/panthor_gpu.c
new file mode 100644
index 000000000000..06b231b2460a
--- /dev/null
+++ b/drivers/gpu/drm/panthor/panthor_gpu.c
@@ -0,0 +1,396 @@
+// SPDX-License-Identifier: GPL-2.0 or MIT
+/* Copyright 2018 Marty E. Plummer <hanetzer@startmail.com> */
+/* Copyright 2019 Linaro, Ltd., Rob Herring <robh@kernel.org> */
+/* Copyright 2019 Collabora ltd. */
+
+#include <linux/bitfield.h>
+#include <linux/bitmap.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+
+#include <drm/drm_drv.h>
+#include <drm/drm_managed.h>
+#include <drm/drm_print.h>
+
+#include "panthor_device.h"
+#include "panthor_gpu.h"
+#include "panthor_hw.h"
+#include "panthor_regs.h"
+
+/**
+ * struct panthor_gpu - GPU block management data.
+ */
+struct panthor_gpu {
+	/** @irq: GPU irq. */
+	struct panthor_irq irq;
+
+	/** @reqs_lock: Lock protecting access to pending_reqs. */
+	spinlock_t reqs_lock;
+
+	/** @pending_reqs: Pending GPU requests. */
+	u32 pending_reqs;
+
+	/** @reqs_acked: GPU request wait queue. */
+	wait_queue_head_t reqs_acked;
+
+	/** @cache_flush_lock: Lock to serialize cache flushes */
+	struct mutex cache_flush_lock;
+};
+
+#define GPU_INTERRUPTS_MASK	\
+	(GPU_IRQ_FAULT | \
+	 GPU_IRQ_PROTM_FAULT | \
+	 GPU_IRQ_RESET_COMPLETED | \
+	 GPU_IRQ_CLEAN_CACHES_COMPLETED)
+
+static void panthor_gpu_coherency_set(struct panthor_device *ptdev)
+{
+	gpu_write(ptdev, GPU_COHERENCY_PROTOCOL,
+		ptdev->coherent ? GPU_COHERENCY_PROT_BIT(ACE_LITE) : GPU_COHERENCY_NONE);
+}
+
+static void panthor_gpu_l2_config_set(struct panthor_device *ptdev)
+{
+	const struct panthor_soc_data *data = ptdev->soc_data;
+	u32 l2_config;
+	u32 i;
+
+	if (!data || !data->asn_hash_enable)
+		return;
+
+	if (GPU_ARCH_MAJOR(ptdev->gpu_info.gpu_id) < 11) {
+		drm_err(&ptdev->base, "Custom ASN hash not supported by the device");
+		return;
+	}
+
+	for (i = 0; i < ARRAY_SIZE(data->asn_hash); i++)
+		gpu_write(ptdev, GPU_ASN_HASH(i), data->asn_hash[i]);
+
+	l2_config = gpu_read(ptdev, GPU_L2_CONFIG);
+	l2_config |= GPU_L2_CONFIG_ASN_HASH_ENABLE;
+	gpu_write(ptdev, GPU_L2_CONFIG, l2_config);
+}
+
+static void panthor_gpu_irq_handler(struct panthor_device *ptdev, u32 status)
+{
+	gpu_write(ptdev, GPU_INT_CLEAR, status);
+
+	if (status & GPU_IRQ_FAULT) {
+		u32 fault_status = gpu_read(ptdev, GPU_FAULT_STATUS);
+		u64 address = gpu_read64(ptdev, GPU_FAULT_ADDR);
+
+		drm_warn(&ptdev->base, "GPU Fault 0x%08x (%s) at 0x%016llx\n",
+			 fault_status, panthor_exception_name(ptdev, fault_status & 0xFF),
+			 address);
+	}
+	if (status & GPU_IRQ_PROTM_FAULT)
+		drm_warn(&ptdev->base, "GPU Fault in protected mode\n");
+
+	spin_lock(&ptdev->gpu->reqs_lock);
+	if (status & ptdev->gpu->pending_reqs) {
+		ptdev->gpu->pending_reqs &= ~status;
+		wake_up_all(&ptdev->gpu->reqs_acked);
+	}
+	spin_unlock(&ptdev->gpu->reqs_lock);
+}
+PANTHOR_IRQ_HANDLER(gpu, GPU, panthor_gpu_irq_handler);
+
+/**
+ * panthor_gpu_unplug() - Called when the GPU is unplugged.
+ * @ptdev: Device to unplug.
+ */
+void panthor_gpu_unplug(struct panthor_device *ptdev)
+{
+	unsigned long flags;
+
+	/* Make sure the IRQ handler is not running after that point. */
+	if (!IS_ENABLED(CONFIG_PM) || pm_runtime_active(ptdev->base.dev))
+		panthor_gpu_irq_suspend(&ptdev->gpu->irq);
+
+	/* Wake-up all waiters. */
+	spin_lock_irqsave(&ptdev->gpu->reqs_lock, flags);
+	ptdev->gpu->pending_reqs = 0;
+	wake_up_all(&ptdev->gpu->reqs_acked);
+	spin_unlock_irqrestore(&ptdev->gpu->reqs_lock, flags);
+}
+
+/**
+ * panthor_gpu_init() - Initialize the GPU block
+ * @ptdev: Device.
+ *
+ * Return: 0 on success, a negative error code otherwise.
+ */
+int panthor_gpu_init(struct panthor_device *ptdev)
+{
+	struct panthor_gpu *gpu;
+	u32 pa_bits;
+	int ret, irq;
+
+	gpu = drmm_kzalloc(&ptdev->base, sizeof(*gpu), GFP_KERNEL);
+	if (!gpu)
+		return -ENOMEM;
+
+	spin_lock_init(&gpu->reqs_lock);
+	init_waitqueue_head(&gpu->reqs_acked);
+	mutex_init(&gpu->cache_flush_lock);
+	ptdev->gpu = gpu;
+
+	dma_set_max_seg_size(ptdev->base.dev, UINT_MAX);
+	pa_bits = GPU_MMU_FEATURES_PA_BITS(ptdev->gpu_info.mmu_features);
+	ret = dma_set_mask_and_coherent(ptdev->base.dev, DMA_BIT_MASK(pa_bits));
+	if (ret)
+		return ret;
+
+	irq = platform_get_irq_byname(to_platform_device(ptdev->base.dev), "gpu");
+	if (irq < 0)
+		return irq;
+
+	ret = panthor_request_gpu_irq(ptdev, &ptdev->gpu->irq, irq, GPU_INTERRUPTS_MASK);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+/**
+ * panthor_gpu_block_power_off() - Power-off a specific block of the GPU
+ * @ptdev: Device.
+ * @blk_name: Block name.
+ * @pwroff_reg: Power-off register for this block.
+ * @pwrtrans_reg: Power transition register for this block.
+ * @mask: Sub-elements to power-off.
+ * @timeout_us: Timeout in microseconds.
+ *
+ * Return: 0 on success, a negative error code otherwise.
+ */
+int panthor_gpu_block_power_off(struct panthor_device *ptdev,
+				const char *blk_name,
+				u32 pwroff_reg, u32 pwrtrans_reg,
+				u64 mask, u32 timeout_us)
+{
+	u32 val;
+	int ret;
+
+	ret = gpu_read64_relaxed_poll_timeout(ptdev, pwrtrans_reg, val,
+					      !(mask & val), 100, timeout_us);
+	if (ret) {
+		drm_err(&ptdev->base,
+			"timeout waiting on %s:%llx power transition", blk_name,
+			mask);
+		return ret;
+	}
+
+	gpu_write64(ptdev, pwroff_reg, mask);
+
+	ret = gpu_read64_relaxed_poll_timeout(ptdev, pwrtrans_reg, val,
+					      !(mask & val), 100, timeout_us);
+	if (ret) {
+		drm_err(&ptdev->base,
+			"timeout waiting on %s:%llx power transition", blk_name,
+			mask);
+		return ret;
+	}
+
+	return 0;
+}
+
+/**
+ * panthor_gpu_block_power_on() - Power-on a specific block of the GPU
+ * @ptdev: Device.
+ * @blk_name: Block name.
+ * @pwron_reg: Power-on register for this block.
+ * @pwrtrans_reg: Power transition register for this block.
+ * @rdy_reg: Power transition ready register.
+ * @mask: Sub-elements to power-on.
+ * @timeout_us: Timeout in microseconds.
+ *
+ * Return: 0 on success, a negative error code otherwise.
+ */
+int panthor_gpu_block_power_on(struct panthor_device *ptdev,
+			       const char *blk_name,
+			       u32 pwron_reg, u32 pwrtrans_reg,
+			       u32 rdy_reg, u64 mask, u32 timeout_us)
+{
+	u32 val;
+	int ret;
+
+	ret = gpu_read64_relaxed_poll_timeout(ptdev, pwrtrans_reg, val,
+					      !(mask & val), 100, timeout_us);
+	if (ret) {
+		drm_err(&ptdev->base,
+			"timeout waiting on %s:%llx power transition", blk_name,
+			mask);
+		return ret;
+	}
+
+	gpu_write64(ptdev, pwron_reg, mask);
+
+	ret = gpu_read64_relaxed_poll_timeout(ptdev, rdy_reg, val,
+					      (mask & val) == val,
+					      100, timeout_us);
+	if (ret) {
+		drm_err(&ptdev->base, "timeout waiting on %s:%llx readiness",
+			blk_name, mask);
+		return ret;
+	}
+
+	return 0;
+}
+
+void panthor_gpu_l2_power_off(struct panthor_device *ptdev)
+{
+	panthor_gpu_power_off(ptdev, L2, ptdev->gpu_info.l2_present, 20000);
+}
+
+/**
+ * panthor_gpu_l2_power_on() - Power-on the L2-cache
+ * @ptdev: Device.
+ *
+ * Return: 0 on success, a negative error code otherwise.
+ */
+int panthor_gpu_l2_power_on(struct panthor_device *ptdev)
+{
+	if (ptdev->gpu_info.l2_present != 1) {
+		/*
+		 * Only support one core group now.
+		 * ~(l2_present - 1) unsets all bits in l2_present except
+		 * the bottom bit. (l2_present - 2) has all the bits in
+		 * the first core group set. AND them together to generate
+		 * a mask of cores in the first core group.
+		 */
+		u64 core_mask = ~(ptdev->gpu_info.l2_present - 1) &
+				(ptdev->gpu_info.l2_present - 2);
+		drm_info_once(&ptdev->base, "using only 1st core group (%lu cores from %lu)\n",
+			      hweight64(core_mask),
+			      hweight64(ptdev->gpu_info.shader_present));
+	}
+
+	/* Set the desired coherency mode and L2 config before the power up of L2 */
+	panthor_gpu_coherency_set(ptdev);
+	panthor_gpu_l2_config_set(ptdev);
+
+	return panthor_gpu_power_on(ptdev, L2, 1, 20000);
+}
+
+/**
+ * panthor_gpu_flush_caches() - Flush caches
+ * @ptdev: Device.
+ * @l2: L2 flush type.
+ * @lsc: LSC flush type.
+ * @other: Other flush type.
+ *
+ * Return: 0 on success, a negative error code otherwise.
+ */
+int panthor_gpu_flush_caches(struct panthor_device *ptdev,
+			     u32 l2, u32 lsc, u32 other)
+{
+	bool timedout = false;
+	unsigned long flags;
+
+	/* Serialize cache flush operations. */
+	guard(mutex)(&ptdev->gpu->cache_flush_lock);
+
+	spin_lock_irqsave(&ptdev->gpu->reqs_lock, flags);
+	if (!drm_WARN_ON(&ptdev->base,
+			 ptdev->gpu->pending_reqs & GPU_IRQ_CLEAN_CACHES_COMPLETED)) {
+		ptdev->gpu->pending_reqs |= GPU_IRQ_CLEAN_CACHES_COMPLETED;
+		gpu_write(ptdev, GPU_CMD, GPU_FLUSH_CACHES(l2, lsc, other));
+	}
+	spin_unlock_irqrestore(&ptdev->gpu->reqs_lock, flags);
+
+	if (!wait_event_timeout(ptdev->gpu->reqs_acked,
+				!(ptdev->gpu->pending_reqs & GPU_IRQ_CLEAN_CACHES_COMPLETED),
+				msecs_to_jiffies(100))) {
+		spin_lock_irqsave(&ptdev->gpu->reqs_lock, flags);
+		if ((ptdev->gpu->pending_reqs & GPU_IRQ_CLEAN_CACHES_COMPLETED) != 0 &&
+		    !(gpu_read(ptdev, GPU_INT_RAWSTAT) & GPU_IRQ_CLEAN_CACHES_COMPLETED))
+			timedout = true;
+		else
+			ptdev->gpu->pending_reqs &= ~GPU_IRQ_CLEAN_CACHES_COMPLETED;
+		spin_unlock_irqrestore(&ptdev->gpu->reqs_lock, flags);
+	}
+
+	if (timedout) {
+		drm_err(&ptdev->base, "Flush caches timeout");
+		return -ETIMEDOUT;
+	}
+
+	return 0;
+}
+
+/**
+ * panthor_gpu_soft_reset() - Issue a soft-reset
+ * @ptdev: Device.
+ *
+ * Return: 0 on success, a negative error code otherwise.
+ */
+int panthor_gpu_soft_reset(struct panthor_device *ptdev)
+{
+	bool timedout = false;
+	unsigned long flags;
+
+	spin_lock_irqsave(&ptdev->gpu->reqs_lock, flags);
+	if (!drm_WARN_ON(&ptdev->base,
+			 ptdev->gpu->pending_reqs & GPU_IRQ_RESET_COMPLETED)) {
+		ptdev->gpu->pending_reqs |= GPU_IRQ_RESET_COMPLETED;
+		gpu_write(ptdev, GPU_INT_CLEAR, GPU_IRQ_RESET_COMPLETED);
+		gpu_write(ptdev, GPU_CMD, GPU_SOFT_RESET);
+	}
+	spin_unlock_irqrestore(&ptdev->gpu->reqs_lock, flags);
+
+	if (!wait_event_timeout(ptdev->gpu->reqs_acked,
+				!(ptdev->gpu->pending_reqs & GPU_IRQ_RESET_COMPLETED),
+				msecs_to_jiffies(100))) {
+		spin_lock_irqsave(&ptdev->gpu->reqs_lock, flags);
+		if ((ptdev->gpu->pending_reqs & GPU_IRQ_RESET_COMPLETED) != 0 &&
+		    !(gpu_read(ptdev, GPU_INT_RAWSTAT) & GPU_IRQ_RESET_COMPLETED))
+			timedout = true;
+		else
+			ptdev->gpu->pending_reqs &= ~GPU_IRQ_RESET_COMPLETED;
+		spin_unlock_irqrestore(&ptdev->gpu->reqs_lock, flags);
+	}
+
+	if (timedout) {
+		drm_err(&ptdev->base, "Soft reset timeout");
+		return -ETIMEDOUT;
+	}
+
+	return 0;
+}
+
+/**
+ * panthor_gpu_suspend() - Suspend the GPU block.
+ * @ptdev: Device.
+ *
+ * Suspend the GPU irq. This should be called last in the suspend procedure,
+ * after all other blocks have been suspented.
+ */
+void panthor_gpu_suspend(struct panthor_device *ptdev)
+{
+	/* On a fast reset, simply power down the L2. */
+	if (!ptdev->reset.fast)
+		panthor_hw_soft_reset(ptdev);
+	else
+		panthor_hw_l2_power_off(ptdev);
+
+	panthor_gpu_irq_suspend(&ptdev->gpu->irq);
+}
+
+/**
+ * panthor_gpu_resume() - Resume the GPU block.
+ * @ptdev: Device.
+ *
+ * Resume the IRQ handler and power-on the L2-cache.
+ * The FW takes care of powering the other blocks.
+ */
+void panthor_gpu_resume(struct panthor_device *ptdev)
+{
+	panthor_gpu_irq_resume(&ptdev->gpu->irq, GPU_INTERRUPTS_MASK);
+	panthor_hw_l2_power_on(ptdev);
+}
+