armv8/fsl-lsch3: Release secondary cores from boot hold off with Boot Page

Secondary cores need to be released from holdoff by boot release
registers. With GPP bootrom, they can boot from main memory
directly. Individual spin table is used for each core. Spin table
and the boot page is reserved in device tree so OS won't overwrite.

Signed-off-by: York Sun <yorksun@freescale.com>
Signed-off-by: Arnab Basu <arnab.basu@freescale.com>

7 files changed, 383 insertions, 20 deletions

diff --git a/arch/arm/cpu/armv8/fsl-lsch3/Makefile b/arch/arm/cpu/armv8/fsl-lsch3/Makefile
index 9249537..f920eeb 100644
--- a/arch/arm/cpu/armv8/fsl-lsch3/Makefile
+++ b/arch/arm/cpu/armv8/fsl-lsch3/Makefile
@@ -7,3 +7,5 @@
 obj-y += cpu.o
 obj-y += lowlevel.o
 obj-y += speed.o
+obj-$(CONFIG_MP) += mp.o
+obj-$(CONFIG_OF_LIBFDT) += fdt.o
diff --git a/arch/arm/cpu/armv8/fsl-lsch3/cpu.c b/arch/arm/cpu/armv8/fsl-lsch3/cpu.c
index c129d03..47b947f 100644
--- a/arch/arm/cpu/armv8/fsl-lsch3/cpu.c
+++ b/arch/arm/cpu/armv8/fsl-lsch3/cpu.c
@@ -11,6 +11,7 @@
 #include <asm/io.h>
 #include <asm/arch-fsl-lsch3/immap_lsch3.h>
 #include "cpu.h"
+#include "mp.h"
 #include "speed.h"
 #include <fsl_mc.h>
 
@@ -434,3 +435,15 @@ int cpu_eth_init(bd_t *bis)
 #endif
 	return error;
 }
+
+
+int arch_early_init_r(void)
+{
+	int rv;
+	rv = fsl_lsch3_wake_seconday_cores();
+
+	if (rv)
+		printf("Did not wake secondary cores\n");
+
+	return 0;
+}
diff --git a/arch/arm/cpu/armv8/fsl-lsch3/cpu.h b/arch/arm/cpu/armv8/fsl-lsch3/cpu.h
index 28544d7..2e3312b 100644
--- a/arch/arm/cpu/armv8/fsl-lsch3/cpu.h
+++ b/arch/arm/cpu/armv8/fsl-lsch3/cpu.h
@@ -5,3 +5,4 @@
  */
 
 int fsl_qoriq_core_to_cluster(unsigned int core);
+u32 cpu_mask(void);
diff --git a/arch/arm/cpu/armv8/fsl-lsch3/fdt.c b/arch/arm/cpu/armv8/fsl-lsch3/fdt.c
new file mode 100644
index 0000000..e392eb9
--- /dev/null
+++ b/arch/arm/cpu/armv8/fsl-lsch3/fdt.c
@@ -0,0 +1,58 @@
+/*
+ * Copyright 2014 Freescale Semiconductor, Inc.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <libfdt.h>
+#include <fdt_support.h>
+#include "mp.h"
+
+#ifdef CONFIG_MP
+void ft_fixup_cpu(void *blob)
+{
+	int off;
+	__maybe_unused u64 spin_tbl_addr = (u64)get_spin_tbl_addr();
+	fdt32_t *reg;
+	int addr_cells;
+	u64 val;
+	size_t *boot_code_size = &(__secondary_boot_code_size);
+
+	off = fdt_path_offset(blob, "/cpus");
+	if (off < 0) {
+		puts("couldn't find /cpus node\n");
+		return;
+	}
+	of_bus_default_count_cells(blob, off, &addr_cells, NULL);
+
+	off = fdt_node_offset_by_prop_value(blob, -1, "device_type", "cpu", 4);
+	while (off != -FDT_ERR_NOTFOUND) {
+		reg = (fdt32_t *)fdt_getprop(blob, off, "reg", 0);
+		if (reg) {
+			val = spin_tbl_addr;
+			val += id_to_core(of_read_number(reg, addr_cells))
+				* SPIN_TABLE_ELEM_SIZE;
+			val = cpu_to_fdt64(val);
+			fdt_setprop_string(blob, off, "enable-method",
+					   "spin-table");
+			fdt_setprop(blob, off, "cpu-release-addr",
+				    &val, sizeof(val));
+		} else {
+			puts("Warning: found cpu node without reg property\n");
+		}
+		off = fdt_node_offset_by_prop_value(blob, off, "device_type",
+						    "cpu", 4);
+	}
+
+	fdt_add_mem_rsv(blob, (uintptr_t)&secondary_boot_code,
+			*boot_code_size);
+}
+#endif
+
+void ft_cpu_setup(void *blob, bd_t *bd)
+{
+#ifdef CONFIG_MP
+	ft_fixup_cpu(blob);
+#endif
+}
diff --git a/arch/arm/cpu/armv8/fsl-lsch3/lowlevel.S b/arch/arm/cpu/armv8/fsl-lsch3/lowlevel.S
index ad32b6c..2a88aab 100644
--- a/arch/arm/cpu/armv8/fsl-lsch3/lowlevel.S
+++ b/arch/arm/cpu/armv8/fsl-lsch3/lowlevel.S
@@ -8,7 +8,9 @@
 
 #include <config.h>
 #include <linux/linkage.h>
+#include <asm/gic.h>
 #include <asm/macro.h>
+#include "mp.h"
 
 ENTRY(lowlevel_init)
 	mov	x29, lr			/* Save LR */
@@ -35,31 +37,114 @@ ENTRY(lowlevel_init)
 #endif
 #endif
 
-	branch_if_master x0, x1, 1f
+	branch_if_master x0, x1, 2f
 
+	ldr	x0, =secondary_boot_func
+	blr	x0
+2:
+	mov	lr, x29			/* Restore LR */
+	ret
+ENDPROC(lowlevel_init)
+
+	/* Keep literals not used by the secondary boot code outside it */
+	.ltorg
+
+	/* Using 64 bit alignment since the spin table is accessed as data */
+	.align 4
+	.global secondary_boot_code
+	/* Secondary Boot Code starts here */
+secondary_boot_code:
+	.global __spin_table
+__spin_table:
+	.space CONFIG_MAX_CPUS*SPIN_TABLE_ELEM_SIZE
+
+	.align 2
+ENTRY(secondary_boot_func)
 	/*
-	 * Slave should wait for master clearing spin table.
-	 * This sync prevent salves observing incorrect
-	 * value of spin table and jumping to wrong place.
+	 * MPIDR_EL1 Fields:
+	 * MPIDR[1:0] = AFF0_CPUID <- Core ID (0,1)
+	 * MPIDR[7:2] = AFF0_RES
+	 * MPIDR[15:8] = AFF1_CLUSTERID <- Cluster ID (0,1,2,3)
+	 * MPIDR[23:16] = AFF2_CLUSTERID
+	 * MPIDR[24] = MT
+	 * MPIDR[29:25] = RES0
+	 * MPIDR[30] = U
+	 * MPIDR[31] = ME
+	 * MPIDR[39:32] = AFF3
+	 *
+	 * Linear Processor ID (LPID) calculation from MPIDR_EL1:
+	 * (We only use AFF0_CPUID and AFF1_CLUSTERID for now
+	 * until AFF2_CLUSTERID and AFF3 have non-zero values)
+	 *
+	 * LPID = MPIDR[15:8] | MPIDR[1:0]
 	 */
-#if defined(CONFIG_GICV2) || defined(CONFIG_GICV3)
-#ifdef CONFIG_GICV2
-	ldr	x0, =GICC_BASE
-#endif
-	bl	gic_wait_for_interrupt
-#endif
-
+	mrs	x0, mpidr_el1
+	ubfm	x1, x0, #8, #15
+	ubfm	x2, x0, #0, #1
+	orr	x10, x2, x1, lsl #2	/* x10 has LPID */
+	ubfm    x9, x0, #0, #15         /* x9 contains MPIDR[15:0] */
 	/*
-	 * All processors will enter EL2 and optionally EL1.
+	 * offset of the spin table element for this core from start of spin
+	 * table (each elem is padded to 64 bytes)
 	 */
-	bl	armv8_switch_to_el2
+	lsl	x1, x10, #6
+	ldr	x0, =__spin_table
+	/* physical address of this cpus spin table element */
+	add	x11, x1, x0
+
+	str	x9, [x11, #16]	/* LPID */
+	mov	x4, #1
+	str	x4, [x11, #8]	/* STATUS */
+	dsb	sy
+#if defined(CONFIG_GICV3)
+	gic_wait_for_interrupt_m x0
+#elif defined(CONFIG_GICV2)
+        ldr     x0, =GICC_BASE
+        gic_wait_for_interrupt_m x0, w1
+#endif
+
+	bl secondary_switch_to_el2
 #ifdef CONFIG_ARMV8_SWITCH_TO_EL1
-	bl	armv8_switch_to_el1
+	bl secondary_switch_to_el1
 #endif
-	b	2f
 
-1:
-2:
-	mov	lr, x29			/* Restore LR */
-	ret
-ENDPROC(lowlevel_init)
+slave_cpu:
+	wfe
+	ldr	x0, [x11]
+	cbz	x0, slave_cpu
+#ifndef CONFIG_ARMV8_SWITCH_TO_EL1
+	mrs     x1, sctlr_el2
+#else
+	mrs     x1, sctlr_el1
+#endif
+	tbz     x1, #25, cpu_is_le
+	rev     x0, x0                  /* BE to LE conversion */
+cpu_is_le:
+	br	x0			/* branch to the given address */
+ENDPROC(secondary_boot_func)
+
+ENTRY(secondary_switch_to_el2)
+	switch_el x0, 1f, 0f, 0f
+0:	ret
+1:	armv8_switch_to_el2_m x0
+ENDPROC(secondary_switch_to_el2)
+
+ENTRY(secondary_switch_to_el1)
+	switch_el x0, 0f, 1f, 0f
+0:	ret
+1:	armv8_switch_to_el1_m x0, x1
+ENDPROC(secondary_switch_to_el1)
+
+	/* Ensure that the literals used by the secondary boot code are
+	 * assembled within it (this is required so that we can protect
+	 * this area with a single memreserve region
+	 */
+	.ltorg
+
+	/* 64 bit alignment for elements accessed as data */
+	.align 4
+	.globl __secondary_boot_code_size
+	.type __secondary_boot_code_size, %object
+	/* Secondary Boot Code ends here */
+__secondary_boot_code_size:
+	.quad .-secondary_boot_code
diff --git a/arch/arm/cpu/armv8/fsl-lsch3/mp.c b/arch/arm/cpu/armv8/fsl-lsch3/mp.c
new file mode 100644
index 0000000..94998bf
--- /dev/null
+++ b/arch/arm/cpu/armv8/fsl-lsch3/mp.c
@@ -0,0 +1,168 @@
+/*
+ * Copyright 2014 Freescale Semiconductor, Inc.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/system.h>
+#include <asm/io.h>
+#include <asm/arch-fsl-lsch3/immap_lsch3.h>
+#include "mp.h"
+
+DECLARE_GLOBAL_DATA_PTR;
+
+void *get_spin_tbl_addr(void)
+{
+	return &__spin_table;
+}
+
+phys_addr_t determine_mp_bootpg(void)
+{
+	return (phys_addr_t)&secondary_boot_code;
+}
+
+int fsl_lsch3_wake_seconday_cores(void)
+{
+	struct ccsr_gur __iomem *gur = (void *)(CONFIG_SYS_FSL_GUTS_ADDR);
+	struct ccsr_reset __iomem *rst = (void *)(CONFIG_SYS_FSL_RST_ADDR);
+	u32 cores, cpu_up_mask = 1;
+	int i, timeout = 10;
+	u64 *table = get_spin_tbl_addr();
+
+	cores = cpu_mask();
+	/* Clear spin table so that secondary processors
+	 * observe the correct value after waking up from wfe.
+	 */
+	memset(table, 0, CONFIG_MAX_CPUS*SPIN_TABLE_ELEM_SIZE);
+	flush_dcache_range((unsigned long)table,
+			   (unsigned long)table +
+			   (CONFIG_MAX_CPUS*SPIN_TABLE_ELEM_SIZE));
+
+	printf("Waking secondary cores to start from %lx\n", gd->relocaddr);
+	out_le32(&gur->bootlocptrh, (u32)(gd->relocaddr >> 32));
+	out_le32(&gur->bootlocptrl, (u32)gd->relocaddr);
+	out_le32(&gur->scratchrw[6], 1);
+	asm volatile("dsb st" : : : "memory");
+	rst->brrl = cores;
+	asm volatile("dsb st" : : : "memory");
+
+	/* This is needed as a precautionary measure.
+	 * If some code before this has accidentally  released the secondary
+	 * cores then the pre-bootloader code will trap them in a "wfe" unless
+	 * the scratchrw[6] is set. In this case we need a sev here to get these
+	 * cores moving again.
+	 */
+	asm volatile("sev");
+
+	while (timeout--) {
+		flush_dcache_range((unsigned long)table, (unsigned long)table +
+				   CONFIG_MAX_CPUS * 64);
+		for (i = 1; i < CONFIG_MAX_CPUS; i++) {
+			if (table[i * WORDS_PER_SPIN_TABLE_ENTRY +
+					SPIN_TABLE_ELEM_STATUS_IDX])
+				cpu_up_mask |= 1 << i;
+		}
+		if (hweight32(cpu_up_mask) == hweight32(cores))
+			break;
+		udelay(10);
+	}
+	if (timeout <= 0) {
+		printf("Not all cores (0x%x) are up (0x%x)\n",
+		       cores, cpu_up_mask);
+		return 1;
+	}
+	printf("All (%d) cores are up.\n", hweight32(cores));
+
+	return 0;
+}
+
+int is_core_valid(unsigned int core)
+{
+	return !!((1 << core) & cpu_mask());
+}
+
+int cpu_reset(int nr)
+{
+	puts("Feature is not implemented.\n");
+
+	return 0;
+}
+
+int cpu_disable(int nr)
+{
+	puts("Feature is not implemented.\n");
+
+	return 0;
+}
+
+int core_to_pos(int nr)
+{
+	u32 cores = cpu_mask();
+	int i, count = 0;
+
+	if (nr == 0) {
+		return 0;
+	} else if (nr >= hweight32(cores)) {
+		puts("Not a valid core number.\n");
+		return -1;
+	}
+
+	for (i = 1; i < 32; i++) {
+		if (is_core_valid(i)) {
+			count++;
+			if (count == nr)
+				break;
+		}
+	}
+
+	return count;
+}
+
+int cpu_status(int nr)
+{
+	u64 *table;
+	int pos;
+
+	if (nr == 0) {
+		table = (u64 *)get_spin_tbl_addr();
+		printf("table base @ 0x%p\n", table);
+	} else {
+		pos = core_to_pos(nr);
+		if (pos < 0)
+			return -1;
+		table = (u64 *)get_spin_tbl_addr() + pos *
+			WORDS_PER_SPIN_TABLE_ENTRY;
+		printf("table @ 0x%p\n", table);
+		printf("   addr - 0x%016llx\n",
+		       table[SPIN_TABLE_ELEM_ENTRY_ADDR_IDX]);
+		printf("   status   - 0x%016llx\n",
+		       table[SPIN_TABLE_ELEM_STATUS_IDX]);
+		printf("   lpid  - 0x%016llx\n",
+		       table[SPIN_TABLE_ELEM_LPID_IDX]);
+	}
+
+	return 0;
+}
+
+int cpu_release(int nr, int argc, char * const argv[])
+{
+	u64 boot_addr;
+	u64 *table = (u64 *)get_spin_tbl_addr();
+	int pos;
+
+	pos = core_to_pos(nr);
+	if (pos <= 0)
+		return -1;
+
+	table += pos * WORDS_PER_SPIN_TABLE_ENTRY;
+	boot_addr = simple_strtoull(argv[0], NULL, 16);
+	table[SPIN_TABLE_ELEM_ENTRY_ADDR_IDX] = boot_addr;
+	flush_dcache_range((unsigned long)table,
+			   (unsigned long)table + SPIN_TABLE_ELEM_SIZE);
+	asm volatile("dsb st");
+	smp_kick_all_cpus();	/* only those with entry addr set will run */
+
+	return 0;
+}
diff --git a/arch/arm/cpu/armv8/fsl-lsch3/mp.h b/arch/arm/cpu/armv8/fsl-lsch3/mp.h
new file mode 100644
index 0000000..06ac0bc
--- /dev/null
+++ b/arch/arm/cpu/armv8/fsl-lsch3/mp.h
@@ -0,0 +1,36 @@
+/*
+ * Copyright 2014, Freescale Semiconductor
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef _FSL_CH3_MP_H
+#define _FSL_CH3_MP_H
+
+/*
+* Each spin table element is defined as
+* struct {
+*      uint64_t entry_addr;
+*      uint64_t status;
+*      uint64_t lpid;
+* };
+* we pad this struct to 64 bytes so each entry is in its own cacheline
+* the actual spin table is an array of these structures
+*/
+#define SPIN_TABLE_ELEM_ENTRY_ADDR_IDX	0
+#define SPIN_TABLE_ELEM_STATUS_IDX	1
+#define SPIN_TABLE_ELEM_LPID_IDX	2
+#define WORDS_PER_SPIN_TABLE_ENTRY	8	/* pad to 64 bytes */
+#define SPIN_TABLE_ELEM_SIZE		64
+
+#define id_to_core(x)	((x & 3) | (x >> 6))
+#ifndef __ASSEMBLY__
+extern u64 __spin_table[];
+extern u64 *secondary_boot_code;
+extern size_t __secondary_boot_code_size;
+int fsl_lsch3_wake_seconday_cores(void);
+void *get_spin_tbl_addr(void);
+phys_addr_t determine_mp_bootpg(void);
+void secondary_boot_func(void);
+#endif
+#endif /* _FSL_CH3_MP_H */