1 files changed, 310 insertions, 34 deletions

diff --git a/arch/arm/mach-mvebu/coherency.c b/arch/arm/mach-mvebu/coherency.c
index 4e9d58148ca7..2bdc3233abe2 100644
--- a/arch/arm/mach-mvebu/coherency.c
+++ b/arch/arm/mach-mvebu/coherency.c
@@ -17,6 +17,8 @@
  * supplies basic routines for configuring and controlling hardware coherency
  */
 
+#define pr_fmt(fmt) "mvebu-coherency: " fmt
+
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/of_address.h>
@@ -24,13 +26,19 @@
 #include <linux/smp.h>
 #include <linux/dma-mapping.h>
 #include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/mbus.h>
+#include <linux/clk.h>
+#include <linux/pci.h>
 #include <asm/smp_plat.h>
 #include <asm/cacheflush.h>
+#include <asm/mach/map.h>
 #include "armada-370-xp.h"
 #include "coherency.h"
+#include "mvebu-soc-id.h"
 
 unsigned long coherency_phys_base;
-static void __iomem *coherency_base;
+void __iomem *coherency_base;
 static void __iomem *coherency_cpu_base;
 
 /* Coherency fabric registers */
@@ -38,27 +46,190 @@ static void __iomem *coherency_cpu_base;
 
 #define IO_SYNC_BARRIER_CTL_OFFSET		   0x0
 
+enum {
+	COHERENCY_FABRIC_TYPE_NONE,
+	COHERENCY_FABRIC_TYPE_ARMADA_370_XP,
+	COHERENCY_FABRIC_TYPE_ARMADA_375,
+	COHERENCY_FABRIC_TYPE_ARMADA_380,
+};
+
 static struct of_device_id of_coherency_table[] = {
-	{.compatible = "marvell,coherency-fabric"},
+	{.compatible = "marvell,coherency-fabric",
+	 .data = (void *) COHERENCY_FABRIC_TYPE_ARMADA_370_XP },
+	{.compatible = "marvell,armada-375-coherency-fabric",
+	 .data = (void *) COHERENCY_FABRIC_TYPE_ARMADA_375 },
+	{.compatible = "marvell,armada-380-coherency-fabric",
+	 .data = (void *) COHERENCY_FABRIC_TYPE_ARMADA_380 },
 	{ /* end of list */ },
 };
 
-/* Function defined in coherency_ll.S */
-int ll_set_cpu_coherent(void __iomem *base_addr, unsigned int hw_cpu_id);
+/* Functions defined in coherency_ll.S */
+int ll_enable_coherency(void);
+void ll_add_cpu_to_smp_group(void);
 
-int set_cpu_coherent(unsigned int hw_cpu_id, int smp_group_id)
+int set_cpu_coherent(void)
 {
 	if (!coherency_base) {
-		pr_warn("Can't make CPU %d cache coherent.\n", hw_cpu_id);
+		pr_warn("Can't make current CPU cache coherent.\n");
 		pr_warn("Coherency fabric is not initialized\n");
 		return 1;
 	}
 
-	return ll_set_cpu_coherent(coherency_base, hw_cpu_id);
+	ll_add_cpu_to_smp_group();
+	return ll_enable_coherency();
+}
+
+/*
+ * The below code implements the I/O coherency workaround on Armada
+ * 375. This workaround consists in using the two channels of the
+ * first XOR engine to trigger a XOR transaction that serves as the
+ * I/O coherency barrier.
+ */
+
+static void __iomem *xor_base, *xor_high_base;
+static dma_addr_t coherency_wa_buf_phys[CONFIG_NR_CPUS];
+static void *coherency_wa_buf[CONFIG_NR_CPUS];
+static bool coherency_wa_enabled;
+
+#define XOR_CONFIG(chan)            (0x10 + (chan * 4))
+#define XOR_ACTIVATION(chan)        (0x20 + (chan * 4))
+#define WINDOW_BAR_ENABLE(chan)     (0x240 + ((chan) << 2))
+#define WINDOW_BASE(w)              (0x250 + ((w) << 2))
+#define WINDOW_SIZE(w)              (0x270 + ((w) << 2))
+#define WINDOW_REMAP_HIGH(w)        (0x290 + ((w) << 2))
+#define WINDOW_OVERRIDE_CTRL(chan)  (0x2A0 + ((chan) << 2))
+#define XOR_DEST_POINTER(chan)      (0x2B0 + (chan * 4))
+#define XOR_BLOCK_SIZE(chan)        (0x2C0 + (chan * 4))
+#define XOR_INIT_VALUE_LOW           0x2E0
+#define XOR_INIT_VALUE_HIGH          0x2E4
+
+static inline void mvebu_hwcc_armada375_sync_io_barrier_wa(void)
+{
+	int idx = smp_processor_id();
+
+	/* Write '1' to the first word of the buffer */
+	writel(0x1, coherency_wa_buf[idx]);
+
+	/* Wait until the engine is idle */
+	while ((readl(xor_base + XOR_ACTIVATION(idx)) >> 4) & 0x3)
+		;
+
+	dmb();
+
+	/* Trigger channel */
+	writel(0x1, xor_base + XOR_ACTIVATION(idx));
+
+	/* Poll the data until it is cleared by the XOR transaction */
+	while (readl(coherency_wa_buf[idx]))
+		;
+}
+
+static void __init armada_375_coherency_init_wa(void)
+{
+	const struct mbus_dram_target_info *dram;
+	struct device_node *xor_node;
+	struct property *xor_status;
+	struct clk *xor_clk;
+	u32 win_enable = 0;
+	int i;
+
+	pr_warn("enabling coherency workaround for Armada 375 Z1, one XOR engine disabled\n");
+
+	/*
+	 * Since the workaround uses one XOR engine, we grab a
+	 * reference to its Device Tree node first.
+	 */
+	xor_node = of_find_compatible_node(NULL, NULL, "marvell,orion-xor");
+	BUG_ON(!xor_node);
+
+	/*
+	 * Then we mark it as disabled so that the real XOR driver
+	 * will not use it.
+	 */
+	xor_status = kzalloc(sizeof(struct property), GFP_KERNEL);
+	BUG_ON(!xor_status);
+
+	xor_status->value = kstrdup("disabled", GFP_KERNEL);
+	BUG_ON(!xor_status->value);
+
+	xor_status->length = 8;
+	xor_status->name = kstrdup("status", GFP_KERNEL);
+	BUG_ON(!xor_status->name);
+
+	of_update_property(xor_node, xor_status);
+
+	/*
+	 * And we remap the registers, get the clock, and do the
+	 * initial configuration of the XOR engine.
+	 */
+	xor_base = of_iomap(xor_node, 0);
+	xor_high_base = of_iomap(xor_node, 1);
+
+	xor_clk = of_clk_get_by_name(xor_node, NULL);
+	BUG_ON(!xor_clk);
+
+	clk_prepare_enable(xor_clk);
+
+	dram = mv_mbus_dram_info();
+
+	for (i = 0; i < 8; i++) {
+		writel(0, xor_base + WINDOW_BASE(i));
+		writel(0, xor_base + WINDOW_SIZE(i));
+		if (i < 4)
+			writel(0, xor_base + WINDOW_REMAP_HIGH(i));
+	}
+
+	for (i = 0; i < dram->num_cs; i++) {
+		const struct mbus_dram_window *cs = dram->cs + i;
+		writel((cs->base & 0xffff0000) |
+		       (cs->mbus_attr << 8) |
+		       dram->mbus_dram_target_id, xor_base + WINDOW_BASE(i));
+		writel((cs->size - 1) & 0xffff0000, xor_base + WINDOW_SIZE(i));
+
+		win_enable |= (1 << i);
+		win_enable |= 3 << (16 + (2 * i));
+	}
+
+	writel(win_enable, xor_base + WINDOW_BAR_ENABLE(0));
+	writel(win_enable, xor_base + WINDOW_BAR_ENABLE(1));
+	writel(0, xor_base + WINDOW_OVERRIDE_CTRL(0));
+	writel(0, xor_base + WINDOW_OVERRIDE_CTRL(1));
+
+	for (i = 0; i < CONFIG_NR_CPUS; i++) {
+		coherency_wa_buf[i] = kzalloc(PAGE_SIZE, GFP_KERNEL);
+		BUG_ON(!coherency_wa_buf[i]);
+
+		/*
+		 * We can't use the DMA mapping API, since we don't
+		 * have a valid 'struct device' pointer
+		 */
+		coherency_wa_buf_phys[i] =
+			virt_to_phys(coherency_wa_buf[i]);
+		BUG_ON(!coherency_wa_buf_phys[i]);
+
+		/*
+		 * Configure the XOR engine for memset operation, with
+		 * a 128 bytes block size
+		 */
+		writel(0x444, xor_base + XOR_CONFIG(i));
+		writel(128, xor_base + XOR_BLOCK_SIZE(i));
+		writel(coherency_wa_buf_phys[i],
+		       xor_base + XOR_DEST_POINTER(i));
+	}
+
+	writel(0x0, xor_base + XOR_INIT_VALUE_LOW);
+	writel(0x0, xor_base + XOR_INIT_VALUE_HIGH);
+
+	coherency_wa_enabled = true;
 }
 
 static inline void mvebu_hwcc_sync_io_barrier(void)
 {
+	if (coherency_wa_enabled) {
+		mvebu_hwcc_armada375_sync_io_barrier_wa();
+		return;
+	}
+
 	writel(0x1, coherency_cpu_base + IO_SYNC_BARRIER_CTL_OFFSET);
 	while (readl(coherency_cpu_base + IO_SYNC_BARRIER_CTL_OFFSET) & 0x1);
 }
@@ -105,8 +276,8 @@ static struct dma_map_ops mvebu_hwcc_dma_ops = {
 	.set_dma_mask		= arm_dma_set_mask,
 };
 
-static int mvebu_hwcc_platform_notifier(struct notifier_block *nb,
-				       unsigned long event, void *__dev)
+static int mvebu_hwcc_notifier(struct notifier_block *nb,
+			       unsigned long event, void *__dev)
 {
 	struct device *dev = __dev;
 
@@ -117,47 +288,152 @@ static int mvebu_hwcc_platform_notifier(struct notifier_block *nb,
 	return NOTIFY_OK;
 }
 
-static struct notifier_block mvebu_hwcc_platform_nb = {
-	.notifier_call = mvebu_hwcc_platform_notifier,
+static struct notifier_block mvebu_hwcc_nb = {
+	.notifier_call = mvebu_hwcc_notifier,
 };
 
-int __init coherency_init(void)
+static struct notifier_block mvebu_hwcc_pci_nb = {
+	.notifier_call = mvebu_hwcc_notifier,
+};
+
+static void __init armada_370_coherency_init(struct device_node *np)
+{
+	struct resource res;
+
+	of_address_to_resource(np, 0, &res);
+	coherency_phys_base = res.start;
+	/*
+	 * Ensure secondary CPUs will see the updated value,
+	 * which they read before they join the coherency
+	 * fabric, and therefore before they are coherent with
+	 * the boot CPU cache.
+	 */
+	sync_cache_w(&coherency_phys_base);
+	coherency_base = of_iomap(np, 0);
+	coherency_cpu_base = of_iomap(np, 1);
+	set_cpu_coherent();
+}
+
+/*
+ * This ioremap hook is used on Armada 375/38x to ensure that PCIe
+ * memory areas are mapped as MT_UNCACHED instead of MT_DEVICE. This
+ * is needed as a workaround for a deadlock issue between the PCIe
+ * interface and the cache controller.
+ */
+static void __iomem *
+armada_pcie_wa_ioremap_caller(phys_addr_t phys_addr, size_t size,
+			      unsigned int mtype, void *caller)
+{
+	struct resource pcie_mem;
+
+	mvebu_mbus_get_pcie_mem_aperture(&pcie_mem);
+
+	if (pcie_mem.start <= phys_addr && (phys_addr + size) <= pcie_mem.end)
+		mtype = MT_UNCACHED;
+
+	return __arm_ioremap_caller(phys_addr, size, mtype, caller);
+}
+
+static void __init armada_375_380_coherency_init(struct device_node *np)
+{
+	struct device_node *cache_dn;
+
+	coherency_cpu_base = of_iomap(np, 0);
+	arch_ioremap_caller = armada_pcie_wa_ioremap_caller;
+
+	/*
+	 * Add the PL310 property "arm,io-coherent". This makes sure the
+	 * outer sync operation is not used, which allows to
+	 * workaround the system erratum that causes deadlocks when
+	 * doing PCIe in an SMP situation on Armada 375 and Armada
+	 * 38x.
+	 */
+	for_each_compatible_node(cache_dn, NULL, "arm,pl310-cache") {
+		struct property *p;
+
+		p = kzalloc(sizeof(*p), GFP_KERNEL);
+		p->name = kstrdup("arm,io-coherent", GFP_KERNEL);
+		of_add_property(cache_dn, p);
+	}
+}
+
+static int coherency_type(void)
 {
 	struct device_node *np;
+	const struct of_device_id *match;
 
-	np = of_find_matching_node(NULL, of_coherency_table);
+	np = of_find_matching_node_and_match(NULL, of_coherency_table, &match);
 	if (np) {
-		struct resource res;
-		pr_info("Initializing Coherency fabric\n");
-		of_address_to_resource(np, 0, &res);
-		coherency_phys_base = res.start;
-		/*
-		 * Ensure secondary CPUs will see the updated value,
-		 * which they read before they join the coherency
-		 * fabric, and therefore before they are coherent with
-		 * the boot CPU cache.
-		 */
-		sync_cache_w(&coherency_phys_base);
-		coherency_base = of_iomap(np, 0);
-		coherency_cpu_base = of_iomap(np, 1);
-		set_cpu_coherent(cpu_logical_map(smp_processor_id()), 0);
-		of_node_put(np);
+		int type = (int) match->data;
+
+		/* Armada 370/XP coherency works in both UP and SMP */
+		if (type == COHERENCY_FABRIC_TYPE_ARMADA_370_XP)
+			return type;
+
+		/* Armada 375 coherency works only on SMP */
+		else if (type == COHERENCY_FABRIC_TYPE_ARMADA_375 && is_smp())
+			return type;
+
+		/* Armada 380 coherency works only on SMP */
+		else if (type == COHERENCY_FABRIC_TYPE_ARMADA_380 && is_smp())
+			return type;
 	}
 
-	return 0;
+	return COHERENCY_FABRIC_TYPE_NONE;
 }
 
-static int __init coherency_late_init(void)
+int coherency_available(void)
+{
+	return coherency_type() != COHERENCY_FABRIC_TYPE_NONE;
+}
+
+int __init coherency_init(void)
 {
+	int type = coherency_type();
 	struct device_node *np;
 
 	np = of_find_matching_node(NULL, of_coherency_table);
-	if (np) {
-		bus_register_notifier(&platform_bus_type,
-				      &mvebu_hwcc_platform_nb);
-		of_node_put(np);
+
+	if (type == COHERENCY_FABRIC_TYPE_ARMADA_370_XP)
+		armada_370_coherency_init(np);
+	else if (type == COHERENCY_FABRIC_TYPE_ARMADA_375 ||
+		 type == COHERENCY_FABRIC_TYPE_ARMADA_380)
+		armada_375_380_coherency_init(np);
+
+	return 0;
+}
+
+static int __init coherency_late_init(void)
+{
+	int type = coherency_type();
+
+	if (type == COHERENCY_FABRIC_TYPE_NONE)
+		return 0;
+
+	if (type == COHERENCY_FABRIC_TYPE_ARMADA_375) {
+		u32 dev, rev;
+
+		if (mvebu_get_soc_id(&dev, &rev) == 0 &&
+		    rev == ARMADA_375_Z1_REV)
+			armada_375_coherency_init_wa();
 	}
+
+	bus_register_notifier(&platform_bus_type,
+			      &mvebu_hwcc_nb);
+
 	return 0;
 }
 
 postcore_initcall(coherency_late_init);
+
+#if IS_ENABLED(CONFIG_PCI)
+static int __init coherency_pci_init(void)
+{
+	if (coherency_available())
+		bus_register_notifier(&pci_bus_type,
+				       &mvebu_hwcc_pci_nb);
+	return 0;
+}
+
+arch_initcall(coherency_pci_init);
+#endif