powerpc/powernv: Remove OPAL v1 takeover

In commit 27f4488872d9 "Add OPAL takeover from PowerVM" we added support
for "takeover" on OPAL v1 machines.

This was a mode of operation where we would boot under pHyp, and query
for the presence of OPAL. If detected we would then do a special
sequence to take over the machine, and the kernel would end up running
in hypervisor mode.

OPAL v1 was never a supported product, and was never shipped outside
IBM. As far as we know no one is still using it.

Newer versions of OPAL do not use the takeover mechanism. Although the
query for OPAL should be harmless on machines with newer OPAL, we have
seen a machine where it causes a crash in Open Firmware.

The code in early_init_devtree() to copy boot_command_line into cmd_line
was added in commit 817c21ad9a1f "Get kernel command line accross OPAL
takeover", and AFAIK is only used by takeover, so should also be
removed.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

3 files changed, 1 insertions, 221 deletions

diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
index 613a860a203c..b694b0730971 100644
--- a/arch/powerpc/kernel/prom.c
+++ b/arch/powerpc/kernel/prom.c
@@ -662,13 +662,6 @@ void __init early_init_devtree(void *params)
 	of_scan_flat_dt(early_init_dt_scan_fw_dump, NULL);
 #endif
 
-	/* Pre-initialize the cmd_line with the content of boot_commmand_line,
-	 * which will be empty except when the content of the variable has
-	 * been overriden by a bootloading mechanism. This happens typically
-	 * with HAL takeover
-	 */
-	strlcpy(cmd_line, boot_command_line, COMMAND_LINE_SIZE);
-
 	/* Retrieve various informations from the /chosen node of the
 	 * device-tree, including the platform type, initrd location and
 	 * size, TCE reserve, and more ...
diff --git a/arch/powerpc/kernel/prom_init.c b/arch/powerpc/kernel/prom_init.c
index 078145acf7fb..1a85d8f96739 100644
--- a/arch/powerpc/kernel/prom_init.c
+++ b/arch/powerpc/kernel/prom_init.c
@@ -1268,201 +1268,6 @@ static u64 __initdata prom_opal_base;
 static u64 __initdata prom_opal_entry;
 #endif
 
-#ifdef __BIG_ENDIAN__
-/* XXX Don't change this structure without updating opal-takeover.S */
-static struct opal_secondary_data {
-	s64				ack;	/*  0 */
-	u64				go;	/*  8 */
-	struct opal_takeover_args	args;	/* 16 */
-} opal_secondary_data;
-
-static u64 __initdata prom_opal_align;
-static u64 __initdata prom_opal_size;
-static int __initdata prom_rtas_start_cpu;
-static u64 __initdata prom_rtas_data;
-static u64 __initdata prom_rtas_entry;
-
-extern char opal_secondary_entry;
-
-static void __init prom_query_opal(void)
-{
-	long rc;
-
-	/* We must not query for OPAL presence on a machine that
-	 * supports TNK takeover (970 blades), as this uses the same
-	 * h-call with different arguments and will crash
-	 */
-	if (PHANDLE_VALID(call_prom("finddevice", 1, 1,
-				    ADDR("/tnk-memory-map")))) {
-		prom_printf("TNK takeover detected, skipping OPAL check\n");
-		return;
-	}
-
-	prom_printf("Querying for OPAL presence... ");
-
-	rc = opal_query_takeover(&prom_opal_size,
-				 &prom_opal_align);
-	prom_debug("(rc = %ld) ", rc);
-	if (rc != 0) {
-		prom_printf("not there.\n");
-		return;
-	}
-	of_platform = PLATFORM_OPAL;
-	prom_printf(" there !\n");
-	prom_debug("  opal_size  = 0x%lx\n", prom_opal_size);
-	prom_debug("  opal_align = 0x%lx\n", prom_opal_align);
-	if (prom_opal_align < 0x10000)
-		prom_opal_align = 0x10000;
-}
-
-static int __init prom_rtas_call(int token, int nargs, int nret,
-				 int *outputs, ...)
-{
-	struct rtas_args rtas_args;
-	va_list list;
-	int i;
-
-	rtas_args.token = token;
-	rtas_args.nargs = nargs;
-	rtas_args.nret  = nret;
-	rtas_args.rets  = (rtas_arg_t *)&(rtas_args.args[nargs]);
-	va_start(list, outputs);
-	for (i = 0; i < nargs; ++i)
-		rtas_args.args[i] = va_arg(list, rtas_arg_t);
-	va_end(list);
-
-	for (i = 0; i < nret; ++i)
-		rtas_args.rets[i] = 0;
-
-	opal_enter_rtas(&rtas_args, prom_rtas_data,
-			prom_rtas_entry);
-
-	if (nret > 1 && outputs != NULL)
-		for (i = 0; i < nret-1; ++i)
-			outputs[i] = rtas_args.rets[i+1];
-	return (nret > 0)? rtas_args.rets[0]: 0;
-}
-
-static void __init prom_opal_hold_cpus(void)
-{
-	int i, cnt, cpu, rc;
-	long j;
-	phandle node;
-	char type[64];
-	u32 servers[8];
-	void *entry = (unsigned long *)&opal_secondary_entry;
-	struct opal_secondary_data *data = &opal_secondary_data;
-
-	prom_debug("prom_opal_hold_cpus: start...\n");
-	prom_debug("    - entry       = 0x%x\n", entry);
-	prom_debug("    - data        = 0x%x\n", data);
-
-	data->ack = -1;
-	data->go = 0;
-
-	/* look for cpus */
-	for (node = 0; prom_next_node(&node); ) {
-		type[0] = 0;
-		prom_getprop(node, "device_type", type, sizeof(type));
-		if (strcmp(type, "cpu") != 0)
-			continue;
-
-		/* Skip non-configured cpus. */
-		if (prom_getprop(node, "status", type, sizeof(type)) > 0)
-			if (strcmp(type, "okay") != 0)
-				continue;
-
-		cnt = prom_getprop(node, "ibm,ppc-interrupt-server#s", servers,
-			     sizeof(servers));
-		if (cnt == PROM_ERROR)
-			break;
-		cnt >>= 2;
-		for (i = 0; i < cnt; i++) {
-			cpu = servers[i];
-			prom_debug("CPU %d ... ", cpu);
-			if (cpu == prom.cpu) {
-				prom_debug("booted !\n");
-				continue;
-			}
-			prom_debug("starting ... ");
-
-			/* Init the acknowledge var which will be reset by
-			 * the secondary cpu when it awakens from its OF
-			 * spinloop.
-			 */
-			data->ack = -1;
-			rc = prom_rtas_call(prom_rtas_start_cpu, 3, 1,
-					    NULL, cpu, entry, data);
-			prom_debug("rtas rc=%d ...", rc);
-
-			for (j = 0; j < 100000000 && data->ack == -1; j++) {
-				HMT_low();
-				mb();
-			}
-			HMT_medium();
-			if (data->ack != -1)
-				prom_debug("done, PIR=0x%x\n", data->ack);
-			else
-				prom_debug("timeout !\n");
-		}
-	}
-	prom_debug("prom_opal_hold_cpus: end...\n");
-}
-
-static void __init prom_opal_takeover(void)
-{
-	struct opal_secondary_data *data = &opal_secondary_data;
-	struct opal_takeover_args *args = &data->args;
-	u64 align = prom_opal_align;
-	u64 top_addr, opal_addr;
-
-	args->k_image	= (u64)_stext;
-	args->k_size	= _end - _stext;
-	args->k_entry	= 0;
-	args->k_entry2	= 0x60;
-
-	top_addr = _ALIGN_UP(args->k_size, align);
-
-	if (prom_initrd_start != 0) {
-		args->rd_image = prom_initrd_start;
-		args->rd_size = prom_initrd_end - args->rd_image;
-		args->rd_loc = top_addr;
-		top_addr = _ALIGN_UP(args->rd_loc + args->rd_size, align);
-	}
-
-	/* Pickup an address for the HAL. We want to go really high
-	 * up to avoid problem with future kexecs. On the other hand
-	 * we don't want to be all over the TCEs on P5IOC2 machines
-	 * which are going to be up there too. We assume the machine
-	 * has plenty of memory, and we ask for the HAL for now to
-	 * be just below the 1G point, or above the initrd
-	 */
-	opal_addr = _ALIGN_DOWN(0x40000000 - prom_opal_size, align);
-	if (opal_addr < top_addr)
-		opal_addr = top_addr;
-	args->hal_addr = opal_addr;
-
-	/* Copy the command line to the kernel image */
-	strlcpy(boot_command_line, prom_cmd_line,
-		COMMAND_LINE_SIZE);
-
-	prom_debug("  k_image    = 0x%lx\n", args->k_image);
-	prom_debug("  k_size     = 0x%lx\n", args->k_size);
-	prom_debug("  k_entry    = 0x%lx\n", args->k_entry);
-	prom_debug("  k_entry2   = 0x%lx\n", args->k_entry2);
-	prom_debug("  hal_addr   = 0x%lx\n", args->hal_addr);
-	prom_debug("  rd_image   = 0x%lx\n", args->rd_image);
-	prom_debug("  rd_size    = 0x%lx\n", args->rd_size);
-	prom_debug("  rd_loc     = 0x%lx\n", args->rd_loc);
-	prom_printf("Performing OPAL takeover,this can take a few minutes..\n");
-	prom_close_stdin();
-	mb();
-	data->go = 1;
-	for (;;)
-		opal_do_takeover(args);
-}
-#endif /* __BIG_ENDIAN__ */
-
 /*
  * Allocate room for and instantiate OPAL
  */
@@ -1597,12 +1402,6 @@ static void __init prom_instantiate_rtas(void)
 			 &val, sizeof(val)) != PROM_ERROR)
 		rtas_has_query_cpu_stopped = true;
 
-#if defined(CONFIG_PPC_POWERNV) && defined(__BIG_ENDIAN__)
-	/* PowerVN takeover hack */
-	prom_rtas_data = base;
-	prom_rtas_entry = entry;
-	prom_getprop(rtas_node, "start-cpu", &prom_rtas_start_cpu, 4);
-#endif
 	prom_debug("rtas base     = 0x%x\n", base);
 	prom_debug("rtas entry    = 0x%x\n", entry);
 	prom_debug("rtas size     = 0x%x\n", (long)size);
@@ -3027,16 +2826,6 @@ unsigned long __init prom_init(unsigned long r3, unsigned long r4,
 		prom_instantiate_rtas();
 
 #ifdef CONFIG_PPC_POWERNV
-#ifdef __BIG_ENDIAN__
-	/* Detect HAL and try instanciating it & doing takeover */
-	if (of_platform == PLATFORM_PSERIES_LPAR) {
-		prom_query_opal();
-		if (of_platform == PLATFORM_OPAL) {
-			prom_opal_hold_cpus();
-			prom_opal_takeover();
-		}
-	} else
-#endif /* __BIG_ENDIAN__ */
 	if (of_platform == PLATFORM_OPAL)
 		prom_instantiate_opal();
 #endif /* CONFIG_PPC_POWERNV */
diff --git a/arch/powerpc/kernel/prom_init_check.sh b/arch/powerpc/kernel/prom_init_check.sh
index 77aa1e95e904..fe8e54b9ef7d 100644
--- a/arch/powerpc/kernel/prom_init_check.sh
+++ b/arch/powerpc/kernel/prom_init_check.sh
@@ -21,9 +21,7 @@ _end enter_prom memcpy memset reloc_offset __secondary_hold
 __secondary_hold_acknowledge __secondary_hold_spinloop __start
 strcmp strcpy strlcpy strlen strncmp strstr logo_linux_clut224
 reloc_got2 kernstart_addr memstart_addr linux_banner _stext
-opal_query_takeover opal_do_takeover opal_enter_rtas opal_secondary_entry
-boot_command_line __prom_init_toc_start __prom_init_toc_end
-btext_setup_display TOC."
+__prom_init_toc_start __prom_init_toc_end btext_setup_display TOC."
 
 NM="$1"
 OBJ="$2"