diff mbox series

[RFC,v4,02/16] Add functions to initialize and start an ultravisor

Message ID 20200227122042.32692-3-grimm@linux.ibm.com
State Superseded
Headers show
Series Ultravisor support in skiboot | expand

Checks

Context Check Description
snowpatch_ozlabs/apply_patch success Successfully applied on branch master (82aed17a5468aff6b600ee1694a10a60f942c018)
snowpatch_ozlabs/snowpatch_job_snowpatch-skiboot success Test snowpatch/job/snowpatch-skiboot on branch master
snowpatch_ozlabs/snowpatch_job_snowpatch-skiboot-dco success Signed-off-by present

Commit Message

Ryan Grimm Feb. 27, 2020, 12:20 p.m. UTC 
Power 9 introduces a mode called ultravisor mode.

init_uv looks for uv-src-address in the device tree and copies the image
to the address specified in "reg".

start_ultravisor is called in load_and_boot_kernel with the pointer to
the system fdt.

Every thread is sent to the ultravisor image and returns with UV mode
off.

A minimal ultravisor could disable UV and PEF, instructions in commit
"skiboot.tcl: ultravisor support."

[ maddy: Initial implementation]
[Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
[ santosh: Initial implementation]
Signed-off-by: Santosh Sivaraj <santosh@fossix.org>
Signed-off-by: Ryan Grimm <grimm@us.ibm.com>
---
 asm/misc.S           | 22 ++++++++++++
 core/init.c          |  6 ++++
 hw/Makefile.inc      |  2 +-
 hw/ultravisor.c      | 81 ++++++++++++++++++++++++++++++++++++++++++++
 include/processor.h  |  8 +++++
 include/ultravisor.h | 17 ++++++++++
 6 files changed, 135 insertions(+), 1 deletion(-)
 create mode 100644 hw/ultravisor.c
 create mode 100644 include/ultravisor.h
diff mbox series

Patch

diff --git a/asm/misc.S b/asm/misc.S
index 647f60b2..f9dea492 100644
--- a/asm/misc.S
+++ b/asm/misc.S
@@ -255,3 +255,25 @@  enter_p9_pm_state:
 	mtspr	SPR_PSSCR,%r3
 	PPC_INST_STOP
 	b	.
+
+/*
+ *  start_uv register usage:
+ *
+ *  r3 : UV base addr
+ *  r4 : system fdt
+ */
+.global start_uv
+start_uv:
+	mflr    %r0
+	std     %r0,16(%r1)
+	sync
+	/* flush caches, etc */
+	icbi    0,%r3
+	sync
+	isync
+	mtctr   %r3
+	mr      %r3,%r4
+	bctrl				/* branch to UV here */
+	ld      %r0,16(%r1)
+	mtlr    %r0
+	blr
diff --git a/core/init.c b/core/init.c
index 339462e5..f124f893 100644
--- a/core/init.c
+++ b/core/init.c
@@ -46,6 +46,7 @@ 
 #include <debug_descriptor.h>
 #include <occ.h>
 #include <opal-dump.h>
+#include <ultravisor.h>
 
 enum proc_gen proc_gen;
 unsigned int pcie_max_link_speed;
@@ -602,6 +603,8 @@  void __noreturn load_and_boot_kernel(bool is_reboot)
 		abort();
 	}
 
+	start_ultravisor(fdt);
+
 	op_display(OP_LOG, OP_MOD_INIT, 0x000C);
 
 	mem_dump_free();
@@ -1354,6 +1357,9 @@  void __noreturn __nomcount main_cpu_entry(const void *fdt)
 	/* Add the list of interrupts going to OPAL */
 	add_opal_interrupts();
 
+	/* Initialize the ultravisor */
+	init_uv();
+
 	/* Now release parts of memory nodes we haven't used ourselves... */
 	mem_region_release_unused();
 
diff --git a/hw/Makefile.inc b/hw/Makefile.inc
index b708bdfe..9a4872ca 100644
--- a/hw/Makefile.inc
+++ b/hw/Makefile.inc
@@ -8,7 +8,7 @@  HW_OBJS += dts.o lpc-rtc.o npu.o npu-hw-procedures.o xive.o phb4.o
 HW_OBJS += fake-nvram.o lpc-mbox.o npu2.o npu2-hw-procedures.o
 HW_OBJS += npu2-common.o npu2-opencapi.o phys-map.o sbe-p9.o capp.o
 HW_OBJS += occ-sensor.o vas.o sbe-p8.o dio-p9.o lpc-port80h.o cache-p9.o
-HW_OBJS += npu-opal.o npu3.o npu3-nvlink.o npu3-hw-procedures.o
+HW_OBJS += npu-opal.o npu3.o npu3-nvlink.o npu3-hw-procedures.o ultravisor.o
 HW=hw/built-in.a
 
 include $(SRC)/hw/fsp/Makefile.inc
diff --git a/hw/ultravisor.c b/hw/ultravisor.c
new file mode 100644
index 00000000..362b7f54
--- /dev/null
+++ b/hw/ultravisor.c
@@ -0,0 +1,81 @@ 
+// SPDX-License-Identifier: Apache-2.0
+/* Copyright 2018-2019 IBM Corp. */
+
+#include <ultravisor.h>
+#include <device.h>
+#include <stdlib.h>
+#include <skiboot.h>
+#include <processor.h>
+#include <opal-api.h>
+#include <cpu.h>
+
+static struct dt_node *uv_fw_node;
+static uint64_t uv_base_addr;
+
+static void cpu_start_ultravisor(void *fdt)
+{
+	prlog(PR_DEBUG, "UV: Starting on CPU 0x%04x\n", this_cpu()->pir);
+	start_uv(uv_base_addr, fdt);
+}
+
+int start_ultravisor(void *fdt)
+{
+	struct cpu_thread *cpu;
+	struct cpu_job **jobs;
+	int i = 0;
+
+	if (!uv_base_addr || !fdt) {
+		prlog(PR_DEBUG, "UV: Bad pointers, not starting\n");
+		return OPAL_INTERNAL_ERROR;
+	}
+
+	jobs = zalloc(sizeof(struct cpu_job *) * cpu_max_pir);
+
+	prlog(PR_DEBUG, "UV: Starting @0x%016llx fdt %p\n",
+				uv_base_addr, fdt);
+
+	for_each_available_cpu(cpu) {
+		if (cpu == this_cpu())
+			continue;
+		jobs[i++] = cpu_queue_job(cpu, "start_ultravisor",
+					cpu_start_ultravisor, fdt);
+	}
+
+	cpu_start_ultravisor(fdt);
+
+	while (i > 0)
+		cpu_wait_job(jobs[--i], true);
+
+	free(jobs);
+
+	return OPAL_SUCCESS;
+}
+
+void init_uv()
+{
+	uint64_t uv_dt_src, uv_fw_sz;
+
+	if (!is_msr_bit_set(MSR_S)) {
+		prlog(PR_DEBUG, "UV: S bit not set\n");
+		return;
+	}
+
+	uv_fw_node = dt_find_compatible_node(dt_root, NULL, "ibm,uv-firmware");
+	if (!uv_fw_node) {
+		prerror("UV: No ibm,uv-firmware node found\n");
+		return;
+	}
+
+	if (!dt_find_property(uv_fw_node, "uv-src-address")) {
+		prerror("UV: No uv-src-address found\n");
+		return;
+	}
+
+	uv_dt_src = dt_prop_get_u64(uv_fw_node, "uv-src-address");
+	uv_base_addr = dt_get_address(uv_fw_node, 0, &uv_fw_sz);
+
+	prlog(PR_INFO, "UV: Copying to protected memory 0x%llx from 0x%llx\n",
+							uv_base_addr, uv_dt_src);
+
+	memcpy((void *)uv_base_addr, (void *)uv_dt_src, UV_LOAD_MAX_SIZE);
+}
diff --git a/include/processor.h b/include/processor.h
index a0c2864a..f1a88d32 100644
--- a/include/processor.h
+++ b/include/processor.h
@@ -11,6 +11,7 @@ 
 #define MSR_HV		PPC_BIT(3)	/* Hypervisor mode */
 #define MSR_VEC		PPC_BIT(38)	/* VMX enable */
 #define MSR_VSX		PPC_BIT(40)	/* VSX enable */
+#define MSR_S		PPC_BIT(41)	/* Secure mode enable */
 #define MSR_EE		PPC_BIT(48)	/* External Int. Enable */
 #define MSR_PR		PPC_BIT(49)       	/* Problem state */
 #define MSR_FP		PPC_BIT(50)	/* Floating Point Enable */
@@ -371,6 +372,13 @@  static inline void st_le32(uint32_t *addr, uint32_t val)
 	asm volatile("stwbrx %0,0,%1" : : "r"(val), "r"(addr), "m"(*addr));
 }
 
+static inline bool is_msr_bit_set(uint64_t bit)
+{
+	if (mfmsr() & bit)
+		return true;
+        return false;
+}
+
 #endif /* __TEST__ */
 
 #endif /* __ASSEMBLY__ */
diff --git a/include/ultravisor.h b/include/ultravisor.h
new file mode 100644
index 00000000..44cf36bf
--- /dev/null
+++ b/include/ultravisor.h
@@ -0,0 +1,17 @@ 
+// SPDX-License-Identifier: Apache-2.0
+/* Copyright 2018-2019 IBM Corp. */
+
+#ifndef __ULTRAVISOR_H
+#define __ULTRAVISOR_H
+
+#include <stdint.h>
+#include <types.h>
+
+#define UV_LOAD_MAX_SIZE        0x200000
+
+extern int start_uv(uint64_t entry, void *fdt);
+
+int start_ultravisor(void *fdt);
+void init_uv(void);
+
+#endif /* __ULTRAVISOR_H */