drivers/iommu/apple_dart.c - filogic/uboot - Gitiles

 // SPDX-License-Identifier: GPL-2.0+
 /*
  * Copyright (C) 2021 Mark Kettenis <kettenis@openbsd.org>
  */

 #include <cpu_func.h>
 #include <dm.h>
 #include <iommu.h>
 #include <lmb.h>
 #include <memalign.h>
 #include <asm/io.h>

 #define DART_PARAMS2		0x0004
 #define  DART_PARAMS2_BYPASS_SUPPORT	BIT(0)

 #define DART_T8020_TLB_CMD		0x0020
 #define  DART_T8020_TLB_CMD_FLUSH		BIT(20)
 #define  DART_T8020_TLB_CMD_BUSY		BIT(2)
 #define DART_T8020_TLB_SIDMASK		0x0034
 #define DART_T8020_ERROR		0x0040
 #define DART_T8020_ERROR_ADDR_LO	0x0050
 #define DART_T8020_ERROR_ADDR_HI	0x0054
 #define DART_T8020_CONFIG		0x0060
 #define  DART_T8020_CONFIG_LOCK			BIT(15)
 #define DART_T8020_SID_ENABLE		0x00fc
 #define DART_T8020_TCR_BASE		0x0100
 #define  DART_T8020_TCR_TRANSLATE_ENABLE	BIT(7)
 #define  DART_T8020_TCR_BYPASS_DART		BIT(8)
 #define  DART_T8020_TCR_BYPASS_DAPF		BIT(12)
 #define DART_T8020_TTBR_BASE		0x0200
 #define  DART_T8020_TTBR_VALID			BIT(31)

 #define DART_T8110_PARAMS4		0x000c
 #define  DART_T8110_PARAMS4_NSID_MASK		(0x1ff << 0)
 #define DART_T8110_TLB_CMD		0x0080
 #define  DART_T8110_TLB_CMD_BUSY		BIT(31)
 #define  DART_T8110_TLB_CMD_FLUSH_ALL		BIT(8)
 #define DART_T8110_ERROR		0x0100
 #define DART_T8110_ERROR_MASK		0x0104
 #define DART_T8110_ERROR_ADDR_LO	0x0170
 #define DART_T8110_ERROR_ADDR_HI	0x0174
 #define DART_T8110_PROTECT		0x0200
 #define  DART_T8110_PROTECT_TTBR_TCR		BIT(0)
 #define DART_T8110_SID_ENABLE_BASE	0x0c00
 #define DART_T8110_TCR_BASE		0x1000
 #define  DART_T8110_TCR_BYPASS_DAPF		BIT(2)
 #define  DART_T8110_TCR_BYPASS_DART		BIT(1)
 #define  DART_T8110_TCR_TRANSLATE_ENABLE	BIT(0)
 #define DART_T8110_TTBR_BASE		0x1400
 #define  DART_T8110_TTBR_VALID			BIT(0)

 #define DART_SID_ENABLE(priv, idx) \
 	((priv)->sid_enable_base + 4 * (idx))
 #define DART_TCR(priv, sid)	((priv)->tcr_base + 4 * (sid))
 #define DART_TTBR(priv, sid, idx)	\
 	((priv)->ttbr_base + 4 * (priv)->nttbr * (sid) + 4 * (idx))
 #define  DART_TTBR_SHIFT	12

 #define DART_ALL_STREAMS(priv)	((1U << (priv)->nsid) - 1)

 #define DART_PAGE_SIZE		SZ_16K
 #define DART_PAGE_MASK		(DART_PAGE_SIZE - 1)

 #define DART_L1_TABLE		0x3
 #define DART_L2_INVAL		0
 #define DART_L2_VALID		BIT(0)
 #define DART_L2_FULL_PAGE	BIT(1)
 #define DART_L2_START(addr)	((((addr) & DART_PAGE_MASK) >> 2) << 52)
 #define DART_L2_END(addr)	((((addr) & DART_PAGE_MASK) >> 2) << 40)

 struct apple_dart_priv {
 	void *base;
 	u64 *l1, *l2;
 	int bypass, shift;

 	dma_addr_t dvabase;
 	dma_addr_t dvaend;

 	int nsid;
 	int nttbr;
 	int sid_enable_base;
 	int tcr_base;
 	u32 tcr_translate_enable;
 	u32 tcr_bypass;
 	int ttbr_base;
 	u32 ttbr_valid;
 	void (*flush_tlb)(struct apple_dart_priv *priv);
 };

 static void apple_dart_t8020_flush_tlb(struct apple_dart_priv *priv)
 {
 	dsb();

 	writel(DART_ALL_STREAMS(priv), priv->base + DART_T8020_TLB_SIDMASK);
 	writel(DART_T8020_TLB_CMD_FLUSH, priv->base + DART_T8020_TLB_CMD);
 	while (readl(priv->base + DART_T8020_TLB_CMD) &
 	       DART_T8020_TLB_CMD_BUSY)
 		continue;
 }

 static void apple_dart_t8110_flush_tlb(struct apple_dart_priv *priv)
 {
 	dsb();

 	writel(DART_T8110_TLB_CMD_FLUSH_ALL,
 	       priv->base + DART_T8110_TLB_CMD_FLUSH_ALL);
 	while (readl(priv->base + DART_T8110_TLB_CMD) &
 	       DART_T8110_TLB_CMD_BUSY)
 		continue;
 }

 static dma_addr_t apple_dart_map(struct udevice *dev, void *addr, size_t size)
 {
 	struct apple_dart_priv *priv = dev_get_priv(dev);
 	phys_addr_t paddr, dva;
 	phys_size_t psize, off;
 	int i, idx;

 	if (priv->bypass)
 		return (phys_addr_t)addr;

 	paddr = ALIGN_DOWN((phys_addr_t)addr, DART_PAGE_SIZE);
 	off = (phys_addr_t)addr - paddr;
 	psize = ALIGN(size + off, DART_PAGE_SIZE);

 	dva = lmb_alloc(psize, DART_PAGE_SIZE);

 	idx = dva / DART_PAGE_SIZE;
 	for (i = 0; i < psize / DART_PAGE_SIZE; i++) {
 		priv->l2[idx + i] = (paddr  >> priv->shift) | DART_L2_VALID |
 			DART_L2_START(0LL) | DART_L2_END(~0LL);
 		paddr += DART_PAGE_SIZE;
 	}
 	flush_dcache_range((unsigned long)&priv->l2[idx],
 			   (unsigned long)&priv->l2[idx + i]);
 	priv->flush_tlb(priv);

 	return dva + off;
 }

 static void apple_dart_unmap(struct udevice *dev, dma_addr_t addr, size_t size)
 {
 	struct apple_dart_priv *priv = dev_get_priv(dev);
 	phys_addr_t dva;
 	phys_size_t psize;
 	int i, idx;

 	if (priv->bypass)
 		return;

 	dva = ALIGN_DOWN(addr, DART_PAGE_SIZE);
 	psize = size + (addr - dva);
 	psize = ALIGN(psize, DART_PAGE_SIZE);

 	idx = dva / DART_PAGE_SIZE;
 	for (i = 0; i < psize / DART_PAGE_SIZE; i++)
 		priv->l2[idx + i] = DART_L2_INVAL;
 	flush_dcache_range((unsigned long)&priv->l2[idx],
 			   (unsigned long)&priv->l2[idx + i]);
 	priv->flush_tlb(priv);

 	lmb_free(dva, psize);
 }

 static struct iommu_ops apple_dart_ops = {
 	.map = apple_dart_map,
 	.unmap = apple_dart_unmap,
 };

 static int apple_dart_probe(struct udevice *dev)
 {
 	struct apple_dart_priv *priv = dev_get_priv(dev);
 	dma_addr_t addr;
 	phys_addr_t l2;
 	int ntte, nl1, nl2;
 	int sid, i;
 	u32 params2, params4;

 	priv->base = dev_read_addr_ptr(dev);
 	if (!priv->base)
 		return -EINVAL;

 	if (device_is_compatible(dev, "apple,t8110-dart")) {
 		params4 = readl(priv->base + DART_T8110_PARAMS4);
 		priv->nsid = params4 & DART_T8110_PARAMS4_NSID_MASK;
 		priv->nttbr = 1;
 		priv->sid_enable_base = DART_T8110_SID_ENABLE_BASE;
 		priv->tcr_base = DART_T8110_TCR_BASE;
 		priv->tcr_translate_enable = DART_T8110_TCR_TRANSLATE_ENABLE;
 		priv->tcr_bypass =
 		    DART_T8110_TCR_BYPASS_DAPF | DART_T8110_TCR_BYPASS_DART;
 		priv->ttbr_base = DART_T8110_TTBR_BASE;
 		priv->ttbr_valid = DART_T8110_TTBR_VALID;
 		priv->flush_tlb = apple_dart_t8110_flush_tlb;
 	} else {
 		priv->nsid = 16;
 		priv->nttbr = 4;
 		priv->sid_enable_base = DART_T8020_SID_ENABLE;
 		priv->tcr_base = DART_T8020_TCR_BASE;
 		priv->tcr_translate_enable = DART_T8020_TCR_TRANSLATE_ENABLE;
 		priv->tcr_bypass =
 		    DART_T8020_TCR_BYPASS_DAPF | DART_T8020_TCR_BYPASS_DART;
 		priv->ttbr_base = DART_T8020_TTBR_BASE;
 		priv->ttbr_valid = DART_T8020_TTBR_VALID;
 		priv->flush_tlb = apple_dart_t8020_flush_tlb;
 	}

 	if (device_is_compatible(dev, "apple,t6000-dart") ||
 	    device_is_compatible(dev, "apple,t8110-dart"))
 		priv->shift = 4;

 	priv->dvabase = DART_PAGE_SIZE;
 	priv->dvaend = SZ_4G - DART_PAGE_SIZE;

 	lmb_add(priv->dvabase, priv->dvaend - priv->dvabase);

 	/* Disable translations. */
 	for (sid = 0; sid < priv->nsid; sid++)
 		writel(0, priv->base + DART_TCR(priv, sid));

 	/* Remove page tables. */
 	for (sid = 0; sid < priv->nsid; sid++) {
 		for (i = 0; i < priv->nttbr; i++)
 			writel(0, priv->base + DART_TTBR(priv, sid, i));
 	}
 	priv->flush_tlb(priv);

 	params2 = readl(priv->base + DART_PARAMS2);
 	if (params2 & DART_PARAMS2_BYPASS_SUPPORT) {
 		for (sid = 0; sid < priv->nsid; sid++) {
 			writel(priv->tcr_bypass,
 			       priv->base + DART_TCR(priv, sid));
 		}
 		priv->bypass = 1;
 		return 0;
 	}

 	ntte = DIV_ROUND_UP(priv->dvaend, DART_PAGE_SIZE);
 	nl2 = DIV_ROUND_UP(ntte, DART_PAGE_SIZE / sizeof(u64));
 	nl1 = DIV_ROUND_UP(nl2, DART_PAGE_SIZE / sizeof(u64));

 	priv->l2 = memalign(DART_PAGE_SIZE, nl2 * DART_PAGE_SIZE);
 	memset(priv->l2, 0, nl2 * DART_PAGE_SIZE);
 	flush_dcache_range((unsigned long)priv->l2,
 			   (unsigned long)priv->l2 + nl2 * DART_PAGE_SIZE);

 	priv->l1 = memalign(DART_PAGE_SIZE, nl1 * DART_PAGE_SIZE);
 	memset(priv->l1, 0, nl1 * DART_PAGE_SIZE);
 	l2 = (phys_addr_t)priv->l2;
 	for (i = 0; i < nl2; i++) {
 		priv->l1[i] = (l2 >> priv->shift) | DART_L1_TABLE;
 		l2 += DART_PAGE_SIZE;
 	}
 	flush_dcache_range((unsigned long)priv->l1,
 			   (unsigned long)priv->l1 + nl1 * DART_PAGE_SIZE);

 	/* Install page tables. */
 	for (sid = 0; sid < priv->nsid; sid++) {
 		addr = (phys_addr_t)priv->l1;
 		for (i = 0; i < nl1; i++) {
 			writel(addr >> DART_TTBR_SHIFT | priv->ttbr_valid,
 			       priv->base + DART_TTBR(priv, sid, i));
 			addr += DART_PAGE_SIZE;
 		}
 	}
 	priv->flush_tlb(priv);

 	/* Enable all streams. */
 	for (i = 0; i < priv->nsid / 32; i++)
 		writel(~0, priv->base + DART_SID_ENABLE(priv, i));

 	/* Enable translations. */
 	for (sid = 0; sid < priv->nsid; sid++) {
 		writel(priv->tcr_translate_enable,
 		       priv->base + DART_TCR(priv, sid));
 	}

 	return 0;
 }

 static int apple_dart_remove(struct udevice *dev)
 {
 	struct apple_dart_priv *priv = dev_get_priv(dev);
 	int sid, i;

 	/* Disable translations. */
 	for (sid = 0; sid < priv->nsid; sid++)
 		writel(0, priv->base + DART_TCR(priv, sid));

 	/* Remove page tables. */
 	for (sid = 0; sid < priv->nsid; sid++) {
 		for (i = 0; i < priv->nttbr; i++)
 			writel(0, priv->base + DART_TTBR(priv, sid, i));
 	}
 	priv->flush_tlb(priv);

 	return 0;
 }

 static const struct udevice_id apple_dart_ids[] = {
 	{ .compatible = "apple,t8103-dart" },
 	{ .compatible = "apple,t6000-dart" },
 	{ .compatible = "apple,t8110-dart" },
 	{ /* sentinel */ }
 };

 U_BOOT_DRIVER(apple_dart) = {
 	.name = "apple_dart",
 	.id = UCLASS_IOMMU,
 	.of_match = apple_dart_ids,
 	.priv_auto = sizeof(struct apple_dart_priv),
 	.ops = &apple_dart_ops,
 	.probe = apple_dart_probe,
 	.remove = apple_dart_remove,
 	.flags	= DM_FLAG_OS_PREPARE
 };
	// SPDX-License-Identifier: GPL-2.0+
	/*
	* Copyright (C) 2021 Mark Kettenis <kettenis@openbsd.org>
	*/

	#include <cpu_func.h>
	#include <dm.h>
	#include <iommu.h>
	#include <lmb.h>
	#include <memalign.h>
	#include <asm/io.h>

	#define DART_PARAMS2 0x0004
	#define DART_PARAMS2_BYPASS_SUPPORT BIT(0)

	#define DART_T8020_TLB_CMD 0x0020
	#define DART_T8020_TLB_CMD_FLUSH BIT(20)
	#define DART_T8020_TLB_CMD_BUSY BIT(2)
	#define DART_T8020_TLB_SIDMASK 0x0034
	#define DART_T8020_ERROR 0x0040
	#define DART_T8020_ERROR_ADDR_LO 0x0050
	#define DART_T8020_ERROR_ADDR_HI 0x0054
	#define DART_T8020_CONFIG 0x0060
	#define DART_T8020_CONFIG_LOCK BIT(15)
	#define DART_T8020_SID_ENABLE 0x00fc
	#define DART_T8020_TCR_BASE 0x0100
	#define DART_T8020_TCR_TRANSLATE_ENABLE BIT(7)
	#define DART_T8020_TCR_BYPASS_DART BIT(8)
	#define DART_T8020_TCR_BYPASS_DAPF BIT(12)
	#define DART_T8020_TTBR_BASE 0x0200
	#define DART_T8020_TTBR_VALID BIT(31)

	#define DART_T8110_PARAMS4 0x000c
	#define DART_T8110_PARAMS4_NSID_MASK (0x1ff << 0)
	#define DART_T8110_TLB_CMD 0x0080
	#define DART_T8110_TLB_CMD_BUSY BIT(31)
	#define DART_T8110_TLB_CMD_FLUSH_ALL BIT(8)
	#define DART_T8110_ERROR 0x0100
	#define DART_T8110_ERROR_MASK 0x0104
	#define DART_T8110_ERROR_ADDR_LO 0x0170
	#define DART_T8110_ERROR_ADDR_HI 0x0174
	#define DART_T8110_PROTECT 0x0200
	#define DART_T8110_PROTECT_TTBR_TCR BIT(0)
	#define DART_T8110_SID_ENABLE_BASE 0x0c00
	#define DART_T8110_TCR_BASE 0x1000
	#define DART_T8110_TCR_BYPASS_DAPF BIT(2)
	#define DART_T8110_TCR_BYPASS_DART BIT(1)
	#define DART_T8110_TCR_TRANSLATE_ENABLE BIT(0)
	#define DART_T8110_TTBR_BASE 0x1400
	#define DART_T8110_TTBR_VALID BIT(0)

	#define DART_SID_ENABLE(priv, idx) \
	((priv)->sid_enable_base + 4 * (idx))
	#define DART_TCR(priv, sid) ((priv)->tcr_base + 4 * (sid))
	#define DART_TTBR(priv, sid, idx) \
	((priv)->ttbr_base + 4 * (priv)->nttbr * (sid) + 4 * (idx))
	#define DART_TTBR_SHIFT 12

	#define DART_ALL_STREAMS(priv) ((1U << (priv)->nsid) - 1)

	#define DART_PAGE_SIZE SZ_16K
	#define DART_PAGE_MASK (DART_PAGE_SIZE - 1)

	#define DART_L1_TABLE 0x3
	#define DART_L2_INVAL 0
	#define DART_L2_VALID BIT(0)
	#define DART_L2_FULL_PAGE BIT(1)
	#define DART_L2_START(addr) ((((addr) & DART_PAGE_MASK) >> 2) << 52)
	#define DART_L2_END(addr) ((((addr) & DART_PAGE_MASK) >> 2) << 40)

	struct apple_dart_priv {
	void *base;
	u64 l1, l2;
	int bypass, shift;

	dma_addr_t dvabase;
	dma_addr_t dvaend;

	int nsid;
	int nttbr;
	int sid_enable_base;
	int tcr_base;
	u32 tcr_translate_enable;
	u32 tcr_bypass;
	int ttbr_base;
	u32 ttbr_valid;
	void (flush_tlb)(struct apple_dart_priv priv);
	};

	static void apple_dart_t8020_flush_tlb(struct apple_dart_priv *priv)
	{
	dsb();

	writel(DART_ALL_STREAMS(priv), priv->base + DART_T8020_TLB_SIDMASK);
	writel(DART_T8020_TLB_CMD_FLUSH, priv->base + DART_T8020_TLB_CMD);
	while (readl(priv->base + DART_T8020_TLB_CMD) &
	DART_T8020_TLB_CMD_BUSY)
	continue;
	}

	static void apple_dart_t8110_flush_tlb(struct apple_dart_priv *priv)
	{
	dsb();

	writel(DART_T8110_TLB_CMD_FLUSH_ALL,
	priv->base + DART_T8110_TLB_CMD_FLUSH_ALL);
	while (readl(priv->base + DART_T8110_TLB_CMD) &
	DART_T8110_TLB_CMD_BUSY)
	continue;
	}

	static dma_addr_t apple_dart_map(struct udevice dev, void addr, size_t size)
	{
	struct apple_dart_priv *priv = dev_get_priv(dev);
	phys_addr_t paddr, dva;
	phys_size_t psize, off;
	int i, idx;

	if (priv->bypass)
	return (phys_addr_t)addr;

	paddr = ALIGN_DOWN((phys_addr_t)addr, DART_PAGE_SIZE);
	off = (phys_addr_t)addr - paddr;
	psize = ALIGN(size + off, DART_PAGE_SIZE);

	dva = lmb_alloc(psize, DART_PAGE_SIZE);

	idx = dva / DART_PAGE_SIZE;
	for (i = 0; i < psize / DART_PAGE_SIZE; i++) {
	priv->l2[idx + i] = (paddr >> priv->shift) \| DART_L2_VALID \|
	DART_L2_START(0LL) \| DART_L2_END(~0LL);
	paddr += DART_PAGE_SIZE;
	}
	flush_dcache_range((unsigned long)&priv->l2[idx],
	(unsigned long)&priv->l2[idx + i]);
	priv->flush_tlb(priv);

	return dva + off;
	}

	static void apple_dart_unmap(struct udevice *dev, dma_addr_t addr, size_t size)
	{
	struct apple_dart_priv *priv = dev_get_priv(dev);
	phys_addr_t dva;
	phys_size_t psize;
	int i, idx;

	if (priv->bypass)
	return;

	dva = ALIGN_DOWN(addr, DART_PAGE_SIZE);
	psize = size + (addr - dva);
	psize = ALIGN(psize, DART_PAGE_SIZE);

	idx = dva / DART_PAGE_SIZE;
	for (i = 0; i < psize / DART_PAGE_SIZE; i++)
	priv->l2[idx + i] = DART_L2_INVAL;
	flush_dcache_range((unsigned long)&priv->l2[idx],
	(unsigned long)&priv->l2[idx + i]);
	priv->flush_tlb(priv);

	lmb_free(dva, psize);
	}

	static struct iommu_ops apple_dart_ops = {
	.map = apple_dart_map,
	.unmap = apple_dart_unmap,
	};

	static int apple_dart_probe(struct udevice *dev)
	{
	struct apple_dart_priv *priv = dev_get_priv(dev);
	dma_addr_t addr;
	phys_addr_t l2;
	int ntte, nl1, nl2;
	int sid, i;
	u32 params2, params4;

	priv->base = dev_read_addr_ptr(dev);
	if (!priv->base)
	return -EINVAL;

	if (device_is_compatible(dev, "apple,t8110-dart")) {
	params4 = readl(priv->base + DART_T8110_PARAMS4);
	priv->nsid = params4 & DART_T8110_PARAMS4_NSID_MASK;
	priv->nttbr = 1;
	priv->sid_enable_base = DART_T8110_SID_ENABLE_BASE;
	priv->tcr_base = DART_T8110_TCR_BASE;
	priv->tcr_translate_enable = DART_T8110_TCR_TRANSLATE_ENABLE;
	priv->tcr_bypass =
	DART_T8110_TCR_BYPASS_DAPF \| DART_T8110_TCR_BYPASS_DART;
	priv->ttbr_base = DART_T8110_TTBR_BASE;
	priv->ttbr_valid = DART_T8110_TTBR_VALID;
	priv->flush_tlb = apple_dart_t8110_flush_tlb;
	} else {
	priv->nsid = 16;
	priv->nttbr = 4;
	priv->sid_enable_base = DART_T8020_SID_ENABLE;
	priv->tcr_base = DART_T8020_TCR_BASE;
	priv->tcr_translate_enable = DART_T8020_TCR_TRANSLATE_ENABLE;
	priv->tcr_bypass =
	DART_T8020_TCR_BYPASS_DAPF \| DART_T8020_TCR_BYPASS_DART;
	priv->ttbr_base = DART_T8020_TTBR_BASE;
	priv->ttbr_valid = DART_T8020_TTBR_VALID;
	priv->flush_tlb = apple_dart_t8020_flush_tlb;
	}

	if (device_is_compatible(dev, "apple,t6000-dart") \|\|
	device_is_compatible(dev, "apple,t8110-dart"))
	priv->shift = 4;

	priv->dvabase = DART_PAGE_SIZE;
	priv->dvaend = SZ_4G - DART_PAGE_SIZE;

	lmb_add(priv->dvabase, priv->dvaend - priv->dvabase);

	/* Disable translations. */
	for (sid = 0; sid < priv->nsid; sid++)
	writel(0, priv->base + DART_TCR(priv, sid));

	/* Remove page tables. */
	for (sid = 0; sid < priv->nsid; sid++) {
	for (i = 0; i < priv->nttbr; i++)
	writel(0, priv->base + DART_TTBR(priv, sid, i));
	}
	priv->flush_tlb(priv);

	params2 = readl(priv->base + DART_PARAMS2);
	if (params2 & DART_PARAMS2_BYPASS_SUPPORT) {
	for (sid = 0; sid < priv->nsid; sid++) {
	writel(priv->tcr_bypass,
	priv->base + DART_TCR(priv, sid));
	}
	priv->bypass = 1;
	return 0;
	}

	ntte = DIV_ROUND_UP(priv->dvaend, DART_PAGE_SIZE);
	nl2 = DIV_ROUND_UP(ntte, DART_PAGE_SIZE / sizeof(u64));
	nl1 = DIV_ROUND_UP(nl2, DART_PAGE_SIZE / sizeof(u64));

	priv->l2 = memalign(DART_PAGE_SIZE, nl2 * DART_PAGE_SIZE);
	memset(priv->l2, 0, nl2 * DART_PAGE_SIZE);
	flush_dcache_range((unsigned long)priv->l2,
	(unsigned long)priv->l2 + nl2 * DART_PAGE_SIZE);

	priv->l1 = memalign(DART_PAGE_SIZE, nl1 * DART_PAGE_SIZE);
	memset(priv->l1, 0, nl1 * DART_PAGE_SIZE);
	l2 = (phys_addr_t)priv->l2;
	for (i = 0; i < nl2; i++) {
	priv->l1[i] = (l2 >> priv->shift) \| DART_L1_TABLE;
	l2 += DART_PAGE_SIZE;
	}
	flush_dcache_range((unsigned long)priv->l1,
	(unsigned long)priv->l1 + nl1 * DART_PAGE_SIZE);

	/* Install page tables. */
	for (sid = 0; sid < priv->nsid; sid++) {
	addr = (phys_addr_t)priv->l1;
	for (i = 0; i < nl1; i++) {
	writel(addr >> DART_TTBR_SHIFT \| priv->ttbr_valid,
	priv->base + DART_TTBR(priv, sid, i));
	addr += DART_PAGE_SIZE;
	}
	}
	priv->flush_tlb(priv);

	/* Enable all streams. */
	for (i = 0; i < priv->nsid / 32; i++)
	writel(~0, priv->base + DART_SID_ENABLE(priv, i));

	/* Enable translations. */
	for (sid = 0; sid < priv->nsid; sid++) {
	writel(priv->tcr_translate_enable,
	priv->base + DART_TCR(priv, sid));
	}

	return 0;
	}

	static int apple_dart_remove(struct udevice *dev)
	{
	struct apple_dart_priv *priv = dev_get_priv(dev);
	int sid, i;

	/* Disable translations. */
	for (sid = 0; sid < priv->nsid; sid++)
	writel(0, priv->base + DART_TCR(priv, sid));

	/* Remove page tables. */
	for (sid = 0; sid < priv->nsid; sid++) {
	for (i = 0; i < priv->nttbr; i++)
	writel(0, priv->base + DART_TTBR(priv, sid, i));
	}
	priv->flush_tlb(priv);

	return 0;
	}

	static const struct udevice_id apple_dart_ids[] = {
	{ .compatible = "apple,t8103-dart" },
	{ .compatible = "apple,t6000-dart" },
	{ .compatible = "apple,t8110-dart" },
	{ /* sentinel */ }
	};

	U_BOOT_DRIVER(apple_dart) = {
	.name = "apple_dart",
	.id = UCLASS_IOMMU,
	.of_match = apple_dart_ids,
	.priv_auto = sizeof(struct apple_dart_priv),
	.ops = &apple_dart_ops,
	.probe = apple_dart_probe,
	.remove = apple_dart_remove,
	.flags = DM_FLAG_OS_PREPARE
	};