1 files changed, 113 insertions, 6 deletions

diff --git a/drivers/bus/arm-cci.c b/drivers/bus/arm-cci.c
index ea81fa4a28db..380319ebf729 100644
--- a/drivers/bus/arm-cci.c
+++ b/drivers/bus/arm-cci.c
@@ -43,6 +43,7 @@ enum cci_ace_port_type {
 
 struct cci_ace_port {
 	void __iomem *base;
+	unsigned long phys;
 	enum cci_ace_port_type type;
 	struct device_node *dn;
 };
@@ -51,11 +52,13 @@ static struct cci_ace_port *ports;
 static unsigned int nb_cci_ports;
 
 static void __iomem *cci_ctrl_base;
+static unsigned long cci_ctrl_phys;
 
 struct cpu_port {
 	u64 mpidr;
 	u32 port;
 };
+
 /*
  * Use the port MSB as valid flag, shift can be made dynamic
  * by computing number of bits required for port indexes.
@@ -230,6 +233,102 @@ int notrace cci_disable_port_by_cpu(u64 mpidr)
 EXPORT_SYMBOL_GPL(cci_disable_port_by_cpu);
 
 /**
+ * cci_enable_port_for_self() - enable a CCI port for calling CPU
+ *
+ * Enabling a CCI port for the calling CPU implies enabling the CCI
+ * port controlling that CPU's cluster. Caller must make sure that the
+ * CPU running the code is the first active CPU in the cluster and all
+ * other CPUs are quiescent in a low power state  or waiting for this CPU
+ * to complete the CCI initialization.
+ *
+ * Because this is called when the MMU is still off and with no stack,
+ * the code must be position independent and ideally rely on callee
+ * clobbered registers only.  To achieve this we must code this function
+ * entirely in assembler.
+ *
+ * On success this returns with the proper CCI port enabled.  In case of
+ * any failure this never returns as the inability to enable the CCI is
+ * fatal and there is no possible recovery at this stage.
+ */
+asmlinkage void __naked cci_enable_port_for_self(void)
+{
+	asm volatile ("\n"
+
+"	mrc	p15, 0, r0, c0, c0, 5	@ get MPIDR value \n"
+"	and	r0, r0, #"__stringify(MPIDR_HWID_BITMASK)" \n"
+"	adr	r1, 5f \n"
+"	ldr	r2, [r1] \n"
+"	add	r1, r1, r2		@ &cpu_port \n"
+"	add	ip, r1, %[sizeof_cpu_port] \n"
+
+	/* Loop over the cpu_port array looking for a matching MPIDR */
+"1:	ldr	r2, [r1, %[offsetof_cpu_port_mpidr_lsb]] \n"
+"	cmp	r2, r0 			@ compare MPIDR \n"
+"	bne	2f \n"
+
+	/* Found a match, now test port validity */
+"	ldr	r3, [r1, %[offsetof_cpu_port_port]] \n"
+"	tst	r3, #"__stringify(PORT_VALID)" \n"
+"	bne	3f \n"
+
+	/* no match, loop with the next cpu_port entry */
+"2:	add	r1, r1, %[sizeof_struct_cpu_port] \n"
+"	cmp	r1, ip			@ done? \n"
+"	blo	1b \n"
+
+	/* CCI port not found -- cheaply try to stall this CPU */
+"cci_port_not_found: \n"
+"	wfi \n"
+"	wfe \n"
+"	b	cci_port_not_found \n"
+
+	/* Use matched port index to look up the corresponding ports entry */
+"3:	bic	r3, r3, #"__stringify(PORT_VALID)" \n"
+"	adr	r0, 6f \n"
+"	ldmia	r0, {r1, r2} \n"
+"	sub	r1, r1, r0 		@ virt - phys \n"
+"	ldr	r0, [r0, r2] 		@ *(&ports) \n"
+"	mov	r2, %[sizeof_struct_ace_port] \n"
+"	mla	r0, r2, r3, r0		@ &ports[index] \n"
+"	sub	r0, r0, r1		@ virt_to_phys() \n"
+
+	/* Enable the CCI port */
+"	ldr	r0, [r0, %[offsetof_port_phys]] \n"
+"	mov	r3, #"__stringify(CCI_ENABLE_REQ)" \n"
+"	str	r3, [r0, #"__stringify(CCI_PORT_CTRL)"] \n"
+
+	/* poll the status reg for completion */
+"	adr	r1, 7f \n"
+"	ldr	r0, [r1] \n"
+"	ldr	r0, [r0, r1]		@ cci_ctrl_base \n"
+"4:	ldr	r1, [r0, #"__stringify(CCI_CTRL_STATUS)"] \n"
+"	tst	r1, #1 \n"
+"	bne	4b \n"
+
+"	mov	r0, #0 \n"
+"	bx	lr \n"
+
+"	.align	2 \n"
+"5:	.word	cpu_port - . \n"
+"6:	.word	. \n"
+"	.word	ports - 6b \n"
+"7:	.word	cci_ctrl_phys - . \n"
+	: :
+	[sizeof_cpu_port] "i" (sizeof(cpu_port)),
+#ifndef __ARMEB__
+	[offsetof_cpu_port_mpidr_lsb] "i" (offsetof(struct cpu_port, mpidr)),
+#else
+	[offsetof_cpu_port_mpidr_lsb] "i" (offsetof(struct cpu_port, mpidr)+4),
+#endif
+	[offsetof_cpu_port_port] "i" (offsetof(struct cpu_port, port)),
+	[sizeof_struct_cpu_port] "i" (sizeof(struct cpu_port)),
+	[sizeof_struct_ace_port] "i" (sizeof(struct cci_ace_port)),
+	[offsetof_port_phys] "i" (offsetof(struct cci_ace_port, phys)) );
+
+	unreachable();
+}
+
+/**
  * __cci_control_port_by_device() - function to control a CCI port by device
  *				    reference
  *
@@ -306,6 +405,7 @@ static int __init cci_probe(void)
 	struct cci_nb_ports const *cci_config;
 	int ret, i, nb_ace = 0, nb_ace_lite = 0;
 	struct device_node *np, *cp;
+	struct resource res;
 	const char *match_str;
 	bool is_ace;
 
@@ -323,9 +423,12 @@ static int __init cci_probe(void)
 	if (!ports)
 		return -ENOMEM;
 
-	cci_ctrl_base = of_iomap(np, 0);
-
-	if (!cci_ctrl_base) {
+	ret = of_address_to_resource(np, 0, &res);
+	if (!ret) {
+		cci_ctrl_base = ioremap(res.start, resource_size(&res));
+		cci_ctrl_phys =	res.start;
+	}
+	if (ret || !cci_ctrl_base) {
 		WARN(1, "unable to ioremap CCI ctrl\n");
 		ret = -ENXIO;
 		goto memalloc_err;
@@ -353,9 +456,12 @@ static int __init cci_probe(void)
 			continue;
 		}
 
-		ports[i].base = of_iomap(cp, 0);
-
-		if (!ports[i].base) {
+		ret = of_address_to_resource(cp, 0, &res);
+		if (!ret) {
+			ports[i].base = ioremap(res.start, resource_size(&res));
+			ports[i].phys = res.start;
+		}
+		if (ret || !ports[i].base) {
 			WARN(1, "unable to ioremap CCI port %d\n", i);
 			continue;
 		}
@@ -382,6 +488,7 @@ static int __init cci_probe(void)
 	 * cluster power-up/power-down. Make sure it reaches main memory.
 	 */
 	sync_cache_w(&cci_ctrl_base);
+	sync_cache_w(&cci_ctrl_phys);
 	sync_cache_w(&ports);
 	sync_cache_w(&cpu_port);
 	__sync_cache_range_w(ports, sizeof(*ports) * nb_cci_ports);