Merge tag 'powerpc-6.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:

 - Add HOTPLUG_SMT support (/sys/devices/system/cpu/smt) and honour the
   configured SMT state when hotplugging CPUs into the system

 - Combine final TLB flush and lazy TLB mm shootdown IPIs when using the
   Radix MMU to avoid a broadcast TLBIE flush on exit

 - Drop the exclusion between ptrace/perf watchpoints, and drop the now
   unused associated arch hooks

 - Add support for the "nohlt" command line option to disable CPU idle

 - Add support for -fpatchable-function-entry for ftrace, with GCC >=
   13.1

 - Rework memory block size determination, and support 256MB size on
   systems with GPUs that have hotpluggable memory

 - Various other small features and fixes

Thanks to Andrew Donnellan, Aneesh Kumar K.V, Arnd Bergmann, Athira
Rajeev, Benjamin Gray, Christophe Leroy, Frederic Barrat, Gautam
Menghani, Geoff Levand, Hari Bathini, Immad Mir, Jialin Zhang, Joel
Stanley, Jordan Niethe, Justin Stitt, Kajol Jain, Kees Cook, Krzysztof
Kozlowski, Laurent Dufour, Liang He, Linus Walleij, Mahesh Salgaonkar,
Masahiro Yamada, Michal Suchanek, Nageswara R Sastry, Nathan Chancellor,
Nathan Lynch, Naveen N Rao, Nicholas Piggin, Nick Desaulniers, Omar
Sandoval, Randy Dunlap, Reza Arbab, Rob Herring, Russell Currey, Sourabh
Jain, Thomas Gleixner, Trevor Woerner, Uwe Kleine-König, Vaibhav Jain,
Xiongfeng Wang, Yuan Tan, Zhang Rui, and Zheng Zengkai.

* tag 'powerpc-6.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (135 commits)
  macintosh/ams: linux/platform_device.h is needed
  powerpc/xmon: Reapply "Relax frame size for clang"
  powerpc/mm/book3s64: Use 256M as the upper limit with coherent device memory attached
  powerpc/mm/book3s64: Fix build error with SPARSEMEM disabled
  powerpc/iommu: Fix notifiers being shared by PCI and VIO buses
  powerpc/mpc5xxx: Add missing fwnode_handle_put()
  powerpc/config: Disable SLAB_DEBUG_ON in skiroot
  powerpc/pseries: Remove unused hcall tracing instruction
  powerpc/pseries: Fix hcall tracepoints with JUMP_LABEL=n
  powerpc: dts: add missing space before {
  powerpc/eeh: Use pci_dev_id() to simplify the code
  powerpc/64s: Move CPU -mtune options into Kconfig
  powerpc/powermac: Fix unused function warning
  powerpc/pseries: Rework lppaca_shared_proc() to avoid DEBUG_PREEMPT
  powerpc: Don't include lppaca.h in paca.h
  powerpc/pseries: Move hcall_vphn() prototype into vphn.h
  powerpc/pseries: Move VPHN constants into vphn.h
  cxl: Drop unused detach_spa()
  powerpc: Drop zalloc_maybe_bootmem()
  powerpc/powernv: Use struct opal_prd_msg in more places
  ...

1 files changed, 127 insertions, 0 deletions

diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c
index e0208cb12058..d96bbc001e73 100644
--- a/arch/powerpc/mm/init_64.c
+++ b/arch/powerpc/mm/init_64.c
@@ -40,6 +40,7 @@
 #include <linux/of_fdt.h>
 #include <linux/libfdt.h>
 #include <linux/memremap.h>
+#include <linux/memory.h>
 
 #include <asm/pgalloc.h>
 #include <asm/page.h>
@@ -493,6 +494,130 @@ static int __init dt_scan_mmu_pid_width(unsigned long node,
 	return 1;
 }
 
+/*
+ * Outside hotplug the kernel uses this value to map the kernel direct map
+ * with radix. To be compatible with older kernels, let's keep this value
+ * as 16M which is also SECTION_SIZE with SPARSEMEM. We can ideally map
+ * things with 1GB size in the case where we don't support hotplug.
+ */
+#ifndef CONFIG_MEMORY_HOTPLUG
+#define DEFAULT_MEMORY_BLOCK_SIZE	SZ_16M
+#else
+#define DEFAULT_MEMORY_BLOCK_SIZE	MIN_MEMORY_BLOCK_SIZE
+#endif
+
+static void update_memory_block_size(unsigned long *block_size, unsigned long mem_size)
+{
+	unsigned long min_memory_block_size = DEFAULT_MEMORY_BLOCK_SIZE;
+
+	for (; *block_size > min_memory_block_size; *block_size >>= 2) {
+		if ((mem_size & *block_size) == 0)
+			break;
+	}
+}
+
+static int __init probe_memory_block_size(unsigned long node, const char *uname, int
+					  depth, void *data)
+{
+	const char *type;
+	unsigned long *block_size = (unsigned long *)data;
+	const __be32 *reg, *endp;
+	int l;
+
+	if (depth != 1)
+		return 0;
+	/*
+	 * If we have dynamic-reconfiguration-memory node, use the
+	 * lmb value.
+	 */
+	if (strcmp(uname, "ibm,dynamic-reconfiguration-memory") == 0) {
+
+		const __be32 *prop;
+
+		prop = of_get_flat_dt_prop(node, "ibm,lmb-size", &l);
+
+		if (!prop || l < dt_root_size_cells * sizeof(__be32))
+			/*
+			 * Nothing in the device tree
+			 */
+			*block_size = DEFAULT_MEMORY_BLOCK_SIZE;
+		else
+			*block_size = of_read_number(prop, dt_root_size_cells);
+		/*
+		 * We have found the final value. Don't probe further.
+		 */
+		return 1;
+	}
+	/*
+	 * Find all the device tree nodes of memory type and make sure
+	 * the area can be mapped using the memory block size value
+	 * we end up using. We start with 1G value and keep reducing
+	 * it such that we can map the entire area using memory_block_size.
+	 * This will be used on powernv and older pseries that don't
+	 * have ibm,lmb-size node.
+	 * For ex: with P5 we can end up with
+	 * memory@0 -> 128MB
+	 * memory@128M -> 64M
+	 * This will end up using 64MB  memory block size value.
+	 */
+	type = of_get_flat_dt_prop(node, "device_type", NULL);
+	if (type == NULL || strcmp(type, "memory") != 0)
+		return 0;
+
+	reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l);
+	if (!reg)
+		reg = of_get_flat_dt_prop(node, "reg", &l);
+	if (!reg)
+		return 0;
+
+	endp = reg + (l / sizeof(__be32));
+	while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
+		const char *compatible;
+		u64 size;
+
+		dt_mem_next_cell(dt_root_addr_cells, &reg);
+		size = dt_mem_next_cell(dt_root_size_cells, &reg);
+
+		if (size) {
+			update_memory_block_size(block_size, size);
+			continue;
+		}
+		/*
+		 * ibm,coherent-device-memory with linux,usable-memory = 0
+		 * Force 256MiB block size. Work around for GPUs on P9 PowerNV
+		 * linux,usable-memory == 0 implies driver managed memory and
+		 * we can't use large memory block size due to hotplug/unplug
+		 * limitations.
+		 */
+		compatible = of_get_flat_dt_prop(node, "compatible", NULL);
+		if (compatible && !strcmp(compatible, "ibm,coherent-device-memory")) {
+			if (*block_size > SZ_256M)
+				*block_size = SZ_256M;
+			/*
+			 * We keep 256M as the upper limit with GPU present.
+			 */
+			return 0;
+		}
+	}
+	/* continue looking for other memory device types */
+	return 0;
+}
+
+/*
+ * start with 1G memory block size. Early init will
+ * fix this with correct value.
+ */
+unsigned long memory_block_size __ro_after_init = 1UL << 30;
+static void __init early_init_memory_block_size(void)
+{
+	/*
+	 * We need to do memory_block_size probe early so that
+	 * radix__early_init_mmu() can use this as limit for
+	 * mapping page size.
+	 */
+	of_scan_flat_dt(probe_memory_block_size, &memory_block_size);
+}
+
 void __init mmu_early_init_devtree(void)
 {
 	bool hvmode = !!(mfmsr() & MSR_HV);
@@ -526,6 +651,8 @@ void __init mmu_early_init_devtree(void)
 	if (!hvmode)
 		early_check_vec5();
 
+	early_init_memory_block_size();
+
 	if (early_radix_enabled()) {
 		radix__early_init_devtree();