mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
* [PATCH v2 0/6] sparc32: replace sp_banks with memblock
@ 2026-08-30 12:06 Magnus Lindholm
  2026-08-30 12:06 ` [PATCH v2 1/6] sparc32: use memblock when mapping the kernel Magnus Lindholm
                   ` (5 more replies)
  0 siblings, 6 replies; 7+ messages in thread
From: Magnus Lindholm @ 2026-08-30 12:06 UTC (permalink / raw)
  To: sparclinux; +Cc: davem, andreas, linux-kernel, sam, glaubitz, Magnus Lindholm

Replace the sparc32-private sp_banks memory description with memblock.

The first two patches convert the SRMMU consumers that already run after
bootmem_init() has populated memblock. The third patch moves memblock
population to prom_meminit() and applies the mem= limit there. Patch 4
removes an unused address bitmap before patch 5 moves the early memory
setup into setup_32.c. Patch 6 removes the now-unused sp_banks array.

This work is based on an earlier eight-patch series by Sam Ravnborg.
Patch 2 directly carries over Sam's memblock sizing conversion. The series
has otherwise been substantially reorganized and reworked for the current
kernel. It retains the sparc32 mem= command-line option by using
memblock_enforce_memory_limit() and uses memblock's exclusive range-end
semantics throughout.

The series applies on top of the sparc32 phys_base and Viking fixes.
setup_memory() preserves relocated-kernel handling by removing RAM below
the physical address to which PAGE_OFFSET maps.

Link: https://lore.kernel.org/sparclinux/20260816075141.3489194-1-linmag7@gmail.com/T/#t

The v1 series was boot tested on a Sun SPARCstation 20 with dual
SuperSPARC-II CPUs (SM71).
The v2 series was boot tested on a Sun SPARCstation 20 with dual
ROSS Hypersparc (RT626) CPUSs.

Changes in v2:
- Add Sam's Reviewed-by tags to patches 1-3 and 6. Patch 6 is the
  unchanged source change from patch 5 in v1, renumbered by the new patch.
- Drop the unused sparc_valid_addr_bitmap in a preparation patch.
- Use for_each_mem_pfn_range() and the standard max_low_pfn variable in
  the early memory setup. This tightens LEON's _pfn_valid() upper bound
  from all memory to the lowmem limit, with no functional change because
  LEON does not use highmem.

Suggested-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://lore.kernel.org/r/20260817153237.GA702187@ravnborg.org

Magnus Lindholm (6):
  sparc32: use memblock when mapping the kernel
  sparc32: use memblock to find available system memory
  sparc32: populate memblock from the PROM memory map
  sparc32: drop unused valid address bitmap
  sparc32: move early memory setup to setup_arch
  sparc32: drop sp_banks

 arch/sparc/include/asm/leon.h       |   2 +-
 arch/sparc/include/asm/page_32.h    |  16 ---
 arch/sparc/include/asm/pgtable_32.h |   3 +-
 arch/sparc/include/asm/pgtsrmmu.h   |   2 +-
 arch/sparc/kernel/setup_32.c        | 115 ++++++++++---------
 arch/sparc/mm/init_32.c             | 167 +---------------------------
 arch/sparc/mm/srmmu.c               |  67 ++++-------
 arch/sparc/prom/memory.c            |  51 ++-------
 8 files changed, 100 insertions(+), 323 deletions(-)


base-commit: e6de5705a9f0d81f67bdb2917108784b5839cecd
-- 
2.43.0

^ permalink raw reply	[flat|nested] 7+ messages in thread

* [PATCH v2 1/6] sparc32: use memblock when mapping the kernel
  2026-08-30 12:06 [PATCH v2 0/6] sparc32: replace sp_banks with memblock Magnus Lindholm
@ 2026-08-30 12:06 ` Magnus Lindholm
  2026-08-30 12:06 ` [PATCH v2 2/6] sparc32: use memblock to find available system memory Magnus Lindholm
                   ` (4 subsequent siblings)
  5 siblings, 0 replies; 7+ messages in thread
From: Magnus Lindholm @ 2026-08-30 12:06 UTC (permalink / raw)
  To: sparclinux; +Cc: davem, andreas, linux-kernel, sam, glaubitz, Magnus Lindholm

memblock already contains the available memory ranges when map_kernel()
runs. Iterate those ranges directly and remove the sp_banks-specific
mapping helper. memblock range ends are exclusive, so use end - start as
the range size.

Suggested-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Magnus Lindholm <linmag7@gmail.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
---
 arch/sparc/mm/srmmu.c | 47 +++++++++++++++++++------------------------
 1 file changed, 21 insertions(+), 26 deletions(-)

diff --git a/arch/sparc/mm/srmmu.c b/arch/sparc/mm/srmmu.c
index f0fe09169528..483235458d69 100644
--- a/arch/sparc/mm/srmmu.c
+++ b/arch/sparc/mm/srmmu.c
@@ -846,39 +846,34 @@ static void __init do_large_mapping(unsigned long vaddr, unsigned long phys_base
 	*__nocache_fix(pgdp) = __pgd(big_pte);
 }
 
-/* Map sp_bank entry SP_ENTRY, starting at virtual address VBASE. */
-static unsigned long __init map_spbank(unsigned long vbase, int sp_entry)
-{
-	unsigned long pstart = (sp_banks[sp_entry].base_addr & PGDIR_MASK);
-	unsigned long vstart = (vbase & PGDIR_MASK);
-	unsigned long vend = PGDIR_ALIGN(vbase + sp_banks[sp_entry].num_bytes);
-	/* Map "low" memory only */
-	const unsigned long min_vaddr = PAGE_OFFSET;
-	const unsigned long max_vaddr = PAGE_OFFSET + SRMMU_MAXMEM;
-
-	if (vstart < min_vaddr || vstart >= max_vaddr)
-		return vstart;
-
-	if (vend > max_vaddr || vend < min_vaddr)
-		vend = max_vaddr;
-
-	while (vstart < vend) {
-		do_large_mapping(vstart, pstart);
-		vstart += PGDIR_SIZE; pstart += PGDIR_SIZE;
-	}
-	return vstart;
-}
-
 static void __init map_kernel(void)
 {
-	int i;
+	phys_addr_t start, end;
+	u64 i;
 
 	if (phys_base > 0) {
 		do_large_mapping(PAGE_OFFSET, phys_base);
 	}
 
-	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
-		map_spbank((unsigned long)__va(sp_banks[i].base_addr), i);
+	for_each_mem_range(i, &start, &end) {
+		unsigned long vbase = (unsigned long)__va(start);
+		unsigned long pstart = start & PGDIR_MASK;
+		unsigned long vstart = vbase & PGDIR_MASK;
+		unsigned long vend = PGDIR_ALIGN(vbase + end - start);
+		const unsigned long min_vaddr = PAGE_OFFSET;
+		const unsigned long max_vaddr = PAGE_OFFSET + SRMMU_MAXMEM;
+
+		/* Map low memory only. */
+		if (vstart < min_vaddr || vstart >= max_vaddr)
+			continue;
+		if (vend > max_vaddr || vend < min_vaddr)
+			vend = max_vaddr;
+
+		while (vstart < vend) {
+			do_large_mapping(vstart, pstart);
+			vstart += PGDIR_SIZE;
+			pstart += PGDIR_SIZE;
+		}
 	}
 }
 
-- 
2.43.0


^ permalink raw reply	[flat|nested] 7+ messages in thread

* [PATCH v2 2/6] sparc32: use memblock to find available system memory
  2026-08-30 12:06 [PATCH v2 0/6] sparc32: replace sp_banks with memblock Magnus Lindholm
  2026-08-30 12:06 ` [PATCH v2 1/6] sparc32: use memblock when mapping the kernel Magnus Lindholm
@ 2026-08-30 12:06 ` Magnus Lindholm
  2026-08-30 12:06 ` [PATCH v2 3/6] sparc32: populate memblock from the PROM memory map Magnus Lindholm
                   ` (3 subsequent siblings)
  5 siblings, 0 replies; 7+ messages in thread
From: Magnus Lindholm @ 2026-08-30 12:06 UTC (permalink / raw)
  To: sparclinux; +Cc: davem, andreas, linux-kernel, sam, glaubitz, Magnus Lindholm

The SRMMU nocache pool is sized after memblock has been populated. Use
memblock_phys_mem_size() instead of summing the private sp_banks array.

Suggested-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Magnus Lindholm <linmag7@gmail.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
---
 arch/sparc/mm/srmmu.c | 14 +-------------
 1 file changed, 1 insertion(+), 13 deletions(-)

diff --git a/arch/sparc/mm/srmmu.c b/arch/sparc/mm/srmmu.c
index 483235458d69..3029527a5a9f 100644
--- a/arch/sparc/mm/srmmu.c
+++ b/arch/sparc/mm/srmmu.c
@@ -226,25 +226,13 @@ void srmmu_free_nocache(void *addr, int size)
 static void srmmu_early_allocate_ptable_skeleton(unsigned long start,
 						 unsigned long end);
 
-/* Return how much physical memory we have.  */
-static unsigned long __init probe_memory(void)
-{
-	unsigned long total = 0;
-	int i;
-
-	for (i = 0; sp_banks[i].num_bytes; i++)
-		total += sp_banks[i].num_bytes;
-
-	return total;
-}
-
 /*
  * Reserve nocache dynamically proportionally to the amount of
  * system RAM. -- Tomas Szepe <szepe@pinerecords.com>, June 2002
  */
 static void __init srmmu_nocache_calcsize(void)
 {
-	unsigned long sysmemavail = probe_memory() / 1024;
+	unsigned long sysmemavail = memblock_phys_mem_size() / 1024;
 	int srmmu_nocache_npages;
 
 	srmmu_nocache_npages =
-- 
2.43.0


^ permalink raw reply	[flat|nested] 7+ messages in thread

* [PATCH v2 3/6] sparc32: populate memblock from the PROM memory map
  2026-08-30 12:06 [PATCH v2 0/6] sparc32: replace sp_banks with memblock Magnus Lindholm
  2026-08-30 12:06 ` [PATCH v2 1/6] sparc32: use memblock when mapping the kernel Magnus Lindholm
  2026-08-30 12:06 ` [PATCH v2 2/6] sparc32: use memblock to find available system memory Magnus Lindholm
@ 2026-08-30 12:06 ` Magnus Lindholm
  2026-08-30 12:06 ` [PATCH v2 4/6] sparc32: drop unused valid address bitmap Magnus Lindholm
                   ` (2 subsequent siblings)
  5 siblings, 0 replies; 7+ messages in thread
From: Magnus Lindholm @ 2026-08-30 12:06 UTC (permalink / raw)
  To: sparclinux; +Cc: davem, andreas, linux-kernel, sam, glaubitz, Magnus Lindholm

Add each available PROM memory range to memblock as it is discovered.
Keep populating sp_banks temporarily so the remaining users continue to
work while they are converted in the following patches.

Since the complete PROM map is now present before bootmem_init(), enforce
the mem= limit after the legacy bank processing. Adding a smaller
overlapping range would otherwise leave memory beyond the requested limit
in memblock during this intermediate commit.

Suggested-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Magnus Lindholm <linmag7@gmail.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
---
 arch/sparc/mm/init_32.c  | 3 +++
 arch/sparc/prom/memory.c | 3 +++
 2 files changed, 6 insertions(+)

diff --git a/arch/sparc/mm/init_32.c b/arch/sparc/mm/init_32.c
index e0e66f91ceeb..75050dfbc2ea 100644
--- a/arch/sparc/mm/init_32.c
+++ b/arch/sparc/mm/init_32.c
@@ -165,6 +165,9 @@ unsigned long __init bootmem_init(unsigned long *pages_avail)
 		memblock_add(sp_banks[i].base_addr, sp_banks[i].num_bytes);
 	}
 
+	if (cmdline_memory_size)
+		memblock_enforce_memory_limit(cmdline_memory_size);
+
 	/* Start with page aligned address of last symbol in kernel
 	 * image.
 	 */
diff --git a/arch/sparc/prom/memory.c b/arch/sparc/prom/memory.c
index 269d6ab5ef5e..59962bc0bc82 100644
--- a/arch/sparc/prom/memory.c
+++ b/arch/sparc/prom/memory.c
@@ -7,6 +7,7 @@
  */
 
 #include <linux/kernel.h>
+#include <linux/memblock.h>
 #include <linux/sort.h>
 #include <linux/init.h>
 
@@ -23,6 +24,7 @@ static int __init prom_meminit_v0(void)
 	for (p = *(romvec->pv_v0mem.v0_available); p; p = p->theres_more) {
 		sp_banks[index].base_addr = (unsigned long) p->start_adr;
 		sp_banks[index].num_bytes = p->num_bytes;
+		memblock_add(p->start_adr, p->num_bytes & PAGE_MASK);
 		index++;
 	}
 
@@ -42,6 +44,7 @@ static int __init prom_meminit_v2(void)
 	for (i = 0; i < num_ents; i++) {
 		sp_banks[i].base_addr = reg[i].phys_addr;
 		sp_banks[i].num_bytes = reg[i].reg_size;
+		memblock_add(reg[i].phys_addr, reg[i].reg_size & PAGE_MASK);
 	}
 
 	return num_ents;
-- 
2.43.0


^ permalink raw reply	[flat|nested] 7+ messages in thread

* [PATCH v2 4/6] sparc32: drop unused valid address bitmap
  2026-08-30 12:06 [PATCH v2 0/6] sparc32: replace sp_banks with memblock Magnus Lindholm
                   ` (2 preceding siblings ...)
  2026-08-30 12:06 ` [PATCH v2 3/6] sparc32: populate memblock from the PROM memory map Magnus Lindholm
@ 2026-08-30 12:06 ` Magnus Lindholm
  2026-08-30 12:06 ` [PATCH v2 5/6] sparc32: move early memory setup to setup_arch Magnus Lindholm
  2026-08-30 12:06 ` [PATCH v2 6/6] sparc32: drop sp_banks Magnus Lindholm
  5 siblings, 0 replies; 7+ messages in thread
From: Magnus Lindholm @ 2026-08-30 12:06 UTC (permalink / raw)
  To: sparclinux; +Cc: davem, andreas, linux-kernel, sam, glaubitz, Magnus Lindholm

sparc_valid_addr_bitmap is populated during early memory setup but never
read. Remove the bitmap, its allocation and the population helper.

Suggested-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Magnus Lindholm <linmag7@gmail.com>
---
 arch/sparc/mm/init_32.c | 36 ------------------------------------
 1 file changed, 36 deletions(-)

diff --git a/arch/sparc/mm/init_32.c b/arch/sparc/mm/init_32.c
index 75050dfbc2ea..6880d9cb30a5 100644
--- a/arch/sparc/mm/init_32.c
+++ b/arch/sparc/mm/init_32.c
@@ -13,7 +13,6 @@
 #include <linux/sched.h>
 #include <linux/kernel.h>
 #include <linux/errno.h>
-#include <linux/string.h>
 #include <linux/types.h>
 #include <linux/ptrace.h>
 #include <linux/mman.h>
@@ -24,7 +23,6 @@
 #include <linux/highmem.h>
 #include <linux/memblock.h>
 #include <linux/pagemap.h>
-#include <linux/poison.h>
 #include <linux/gfp.h>
 
 #include <asm/sections.h>
@@ -37,8 +35,6 @@
 
 #include "mm_32.h"
 
-static unsigned long *sparc_valid_addr_bitmap;
-
 unsigned long phys_base;
 EXPORT_SYMBOL(phys_base);
 
@@ -218,27 +214,8 @@ void __init paging_init(void)
 	device_scan();
 }
 
-static void __init taint_real_pages(void)
-{
-	int i;
-
-	for (i = 0; sp_banks[i].num_bytes; i++) {
-		unsigned long start, end;
-
-		start = sp_banks[i].base_addr;
-		end = start + sp_banks[i].num_bytes;
-
-		while (start < end) {
-			set_bit(start >> 20, sparc_valid_addr_bitmap);
-			start += PAGE_SIZE;
-		}
-	}
-}
-
 void __init arch_mm_preinit(void)
 {
-	int i;
-
 	if (PKMAP_BASE+LAST_PKMAP*PAGE_SIZE >= FIXADDR_START) {
 		prom_printf("BUG: fixmap and pkmap areas overlap\n");
 		prom_printf("pkbase: 0x%lx pkend: 0x%lx fixstart 0x%lx\n",
@@ -248,19 +225,6 @@ void __init arch_mm_preinit(void)
 		prom_printf("Please mail sparclinux@vger.kernel.org.\n");
 		prom_halt();
 	}
-
-	i = last_valid_pfn >> ((20 - PAGE_SHIFT) + 5);
-	i += 1;
-	sparc_valid_addr_bitmap = (unsigned long *)
-		memblock_alloc(i << 2, SMP_CACHE_BYTES);
-
-	if (sparc_valid_addr_bitmap == NULL) {
-		prom_printf("mem_init: Cannot alloc valid_addr_bitmap.\n");
-		prom_halt();
-	}
-	memset(sparc_valid_addr_bitmap, 0, i << 2);
-
-	taint_real_pages();
 }
 
 void sparc_flush_page_to_ram(struct page *page)
-- 
2.43.0


^ permalink raw reply	[flat|nested] 7+ messages in thread

* [PATCH v2 5/6] sparc32: move early memory setup to setup_arch
  2026-08-30 12:06 [PATCH v2 0/6] sparc32: replace sp_banks with memblock Magnus Lindholm
                   ` (3 preceding siblings ...)
  2026-08-30 12:06 ` [PATCH v2 4/6] sparc32: drop unused valid address bitmap Magnus Lindholm
@ 2026-08-30 12:06 ` Magnus Lindholm
  2026-08-30 12:06 ` [PATCH v2 6/6] sparc32: drop sp_banks Magnus Lindholm
  5 siblings, 0 replies; 7+ messages in thread
From: Magnus Lindholm @ 2026-08-30 12:06 UTC (permalink / raw)
  To: sparclinux; +Cc: davem, andreas, linux-kernel, sam, glaubitz, Magnus Lindholm

Move the early memory configuration out of SRMMU paging setup and next to
the rest of setup_arch(). Derive the PFN limits from memblock, reserve the
kernel and initrd there, and retain mem= support with
memblock_enforce_memory_limit().

Use for_each_mem_pfn_range() to find the lowmem boundary and replace
last_valid_pfn with the standard max_low_pfn variable. This tightens
LEON's _pfn_valid() upper bound from all RAM to the lowmem limit, with no
functional change because LEON does not use highmem.

When PAGE_OFFSET maps a relocated kernel, remove memory below phys_base
from memblock because it cannot be reached through the linear map. This
replaces the equivalent trimming of sp_banks.

Suggested-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Magnus Lindholm <linmag7@gmail.com>
---
 arch/sparc/include/asm/leon.h       |   2 +-
 arch/sparc/include/asm/pgtable_32.h |   3 +-
 arch/sparc/include/asm/pgtsrmmu.h   |   2 +-
 arch/sparc/kernel/setup_32.c        | 115 +++++++++++++-----------
 arch/sparc/mm/init_32.c             | 132 +---------------------------
 arch/sparc/mm/srmmu.c               |   6 --
 6 files changed, 69 insertions(+), 191 deletions(-)

diff --git a/arch/sparc/include/asm/leon.h b/arch/sparc/include/asm/leon.h
index 053a24b67aed..815131c77ed7 100644
--- a/arch/sparc/include/asm/leon.h
+++ b/arch/sparc/include/asm/leon.h
@@ -251,7 +251,7 @@ extern int leon_ipi_irq;
 
 /* macros used in leon_mm.c */
 #define PFN(x)           ((x) >> PAGE_SHIFT)
-#define _pfn_valid(pfn)	 ((pfn < last_valid_pfn) && (pfn >= PFN(phys_base)))
+#define _pfn_valid(pfn)	 ((pfn < max_low_pfn) && (pfn >= PFN(phys_base)))
 #define _SRMMU_PTE_PMASK_LEON 0xffffffff
 
 /*
diff --git a/arch/sparc/include/asm/pgtable_32.h b/arch/sparc/include/asm/pgtable_32.h
index f89b1250661d..91a6032cf6a2 100644
--- a/arch/sparc/include/asm/pgtable_32.h
+++ b/arch/sparc/include/asm/pgtable_32.h
@@ -37,8 +37,7 @@ struct vm_area_struct;
 struct page;
 
 void load_mmu(void);
-unsigned long calc_highpages(void);
-unsigned long __init bootmem_init(unsigned long *pages_avail);
+void __init find_ramdisk(unsigned long end_of_phys_memory);
 
 #define pte_ERROR(e)   __builtin_trap()
 #define pmd_ERROR(e)   __builtin_trap()
diff --git a/arch/sparc/include/asm/pgtsrmmu.h b/arch/sparc/include/asm/pgtsrmmu.h
index a265822a475e..9ce7558113f8 100644
--- a/arch/sparc/include/asm/pgtsrmmu.h
+++ b/arch/sparc/include/asm/pgtsrmmu.h
@@ -98,7 +98,7 @@
 	 restore %g0, %g0, %g0;
 
 #ifndef __ASSEMBLER__
-extern unsigned long last_valid_pfn;
+extern unsigned long max_low_pfn;
 
 /* This makes sense. Honest it does - Anton */
 /* XXX Yes but it's ugly as sin.  FIXME. -KMW */
diff --git a/arch/sparc/kernel/setup_32.c b/arch/sparc/kernel/setup_32.c
index 795714959da6..c3c3274e55af 100644
--- a/arch/sparc/kernel/setup_32.c
+++ b/arch/sparc/kernel/setup_32.c
@@ -23,6 +23,7 @@
 #include <linux/syscalls.h>
 #include <linux/kdev_t.h>
 #include <linux/major.h>
+#include <linux/memblock.h>
 #include <linux/string.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
@@ -254,28 +255,74 @@ static __init void leon_patch(void)
 
 struct tt_entry *sparc_ttable;
 
-/* Drop RAM below the kernel; the linear map runs upward from phys_base
- * and cannot reach it.
- */
-static void __init trim_sp_banks_below(unsigned long base)
+unsigned long phys_base;
+EXPORT_SYMBOL(phys_base);
+
+unsigned long pfn_base;
+EXPORT_SYMBOL(pfn_base);
+
+unsigned long highend_pfn;
+
+static unsigned long __init calc_max_low_pfn(void)
 {
-	int i, j = 0;
+	unsigned long limit = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
+	unsigned long start_pfn, end_pfn;
+	unsigned long last_pfn = 0;
+	int i;
+
+	for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn,
+			       NULL) {
+		if (start_pfn >= limit) {
+			if (last_pfn < limit)
+				limit = last_pfn;
+			break;
+		}
 
-	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
-		unsigned long start = sp_banks[i].base_addr;
-		unsigned long end = start + sp_banks[i].num_bytes;
+		last_pfn = end_pfn;
+	}
 
-		if (end <= base)
-			continue;		/* wholly below - drop it */
-		if (start < base)
-			start = base;		/* straddles - trim the front */
+	return limit;
+}
 
-		sp_banks[j].base_addr = start;
-		sp_banks[j].num_bytes = end - start;
-		j++;
+static void __init setup_memory(void)
+{
+	unsigned long ram_base = memblock_start_of_DRAM();
+	unsigned long real_base = __get_phys(PAGE_OFFSET);
+	unsigned long size;
+
+	memblock_set_bottom_up(true);
+	memblock_allow_resize();
+
+	phys_base = ram_base;
+	if (real_base && real_base != phys_base) {
+		prom_printf("phys_base: RAM starts 0x%x but kernel is at 0x%x\n",
+			    (unsigned int)phys_base, (unsigned int)real_base);
+		phys_base = real_base;
+		memblock_remove(0, phys_base);
+		prom_printf("phys_base: adopted 0x%x, RAM below it dropped\n",
+			    (unsigned int)phys_base);
 	}
-	sp_banks[j].base_addr = 0;
-	sp_banks[j].num_bytes = 0;
+
+	if (cmdline_memory_size)
+		memblock_enforce_memory_limit(cmdline_memory_size);
+
+	min_low_pfn = PFN_DOWN(memblock_start_of_DRAM());
+	pfn_base = phys_base >> PAGE_SHIFT;
+	max_low_pfn = PFN_DOWN(memblock_end_of_DRAM());
+	highend_pfn = max_low_pfn;
+
+	if (max_low_pfn > pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT))
+		max_low_pfn = calc_max_low_pfn();
+
+	find_ramdisk(memblock_end_of_DRAM());
+
+	/* Reserve the kernel text/data/bss. */
+	size = __pa(PAGE_ALIGN((unsigned long)&_end)) - phys_base;
+	memblock_reserve(phys_base, size);
+	memblock_add(phys_base, size);
+
+	/* Only allow low memory to be allocated by memblock. */
+	memblock_set_current_limit(PFN_PHYS(max_low_pfn));
 }
 
 /* Called from head_32.S - before we have setup anything
@@ -306,9 +353,6 @@ void __init sparc32_start_kernel(struct linux_romvec *rp)
 
 void __init setup_arch(char **cmdline_p)
 {
-	int i;
-	unsigned long highest_paddr;
-
 	sparc_ttable = &trapbase[0];
 
 	/* Initialize PROM console and command line. */
@@ -343,36 +387,7 @@ void __init setup_arch(char **cmdline_p)
 
 	idprom_init();
 	load_mmu();
-
-	phys_base = 0xffffffffUL;
-	highest_paddr = 0UL;
-	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
-		unsigned long top;
-
-		if (sp_banks[i].base_addr < phys_base)
-			phys_base = sp_banks[i].base_addr;
-		top = sp_banks[i].base_addr +
-			sp_banks[i].num_bytes;
-		if (highest_paddr < top)
-			highest_paddr = top;
-	}
-
-	/* phys_base must describe what PAGE_OFFSET maps to, not where RAM starts. */
-	{
-		unsigned long real_base = __get_phys(PAGE_OFFSET);
-
-		if (real_base && real_base != phys_base) {
-			prom_printf("phys_base: RAM starts 0x%x but kernel is at 0x%x\n",
-				    (unsigned int)phys_base,
-				    (unsigned int)real_base);
-			phys_base = real_base;
-			trim_sp_banks_below(phys_base);
-			prom_printf("phys_base: adopted 0x%x, RAM below it dropped\n",
-				    (unsigned int)phys_base);
-		}
-	}
-
-	pfn_base = phys_base >> PAGE_SHIFT;
+	setup_memory();
 
 	if (!root_flags)
 		root_mountflags &= ~MS_RDONLY;
diff --git a/arch/sparc/mm/init_32.c b/arch/sparc/mm/init_32.c
index 6880d9cb30a5..ac4462f1cf76 100644
--- a/arch/sparc/mm/init_32.c
+++ b/arch/sparc/mm/init_32.c
@@ -35,66 +35,13 @@
 
 #include "mm_32.h"
 
-unsigned long phys_base;
-EXPORT_SYMBOL(phys_base);
-
-unsigned long pfn_base;
-EXPORT_SYMBOL(pfn_base);
-
 struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS+1];
 
 /* Initial ramdisk setup */
 extern unsigned int sparc_ramdisk_image;
 extern unsigned int sparc_ramdisk_size;
 
-unsigned long highstart_pfn, highend_pfn;
-
-unsigned long last_valid_pfn;
-
-unsigned long calc_highpages(void)
-{
-	int i;
-	int nr = 0;
-
-	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
-		unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
-		unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
-
-		if (end_pfn <= max_low_pfn)
-			continue;
-
-		if (start_pfn < max_low_pfn)
-			start_pfn = max_low_pfn;
-
-		nr += end_pfn - start_pfn;
-	}
-
-	return nr;
-}
-
-static unsigned long calc_max_low_pfn(void)
-{
-	int i;
-	unsigned long tmp = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
-	unsigned long curr_pfn, last_pfn;
-
-	last_pfn = (sp_banks[0].base_addr + sp_banks[0].num_bytes) >> PAGE_SHIFT;
-	for (i = 1; sp_banks[i].num_bytes != 0; i++) {
-		curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
-
-		if (curr_pfn >= tmp) {
-			if (last_pfn < tmp)
-				tmp = last_pfn;
-			break;
-		}
-
-		last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
-	}
-
-	return tmp;
-}
-
-static void __init find_ramdisk(unsigned long end_of_phys_memory)
+void __init find_ramdisk(unsigned long end_of_phys_memory)
 {
 #ifdef CONFIG_BLK_DEV_INITRD
 	unsigned long size;
@@ -124,83 +71,6 @@ static void __init find_ramdisk(unsigned long end_of_phys_memory)
 #endif
 }
 
-unsigned long __init bootmem_init(unsigned long *pages_avail)
-{
-	unsigned long start_pfn, bytes_avail, size;
-	unsigned long end_of_phys_memory = 0;
-	unsigned long high_pages = 0;
-	int i;
-
-	memblock_set_bottom_up(true);
-	memblock_allow_resize();
-
-	bytes_avail = 0UL;
-	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
-		end_of_phys_memory = sp_banks[i].base_addr +
-			sp_banks[i].num_bytes;
-		bytes_avail += sp_banks[i].num_bytes;
-		if (cmdline_memory_size) {
-			if (bytes_avail > cmdline_memory_size) {
-				unsigned long slack = bytes_avail - cmdline_memory_size;
-
-				bytes_avail -= slack;
-				end_of_phys_memory -= slack;
-
-				sp_banks[i].num_bytes -= slack;
-				if (sp_banks[i].num_bytes == 0) {
-					sp_banks[i].base_addr = 0xdeadbeef;
-				} else {
-					memblock_add(sp_banks[i].base_addr,
-						     sp_banks[i].num_bytes);
-					sp_banks[i+1].num_bytes = 0;
-					sp_banks[i+1].base_addr = 0xdeadbeef;
-				}
-				break;
-			}
-		}
-		memblock_add(sp_banks[i].base_addr, sp_banks[i].num_bytes);
-	}
-
-	if (cmdline_memory_size)
-		memblock_enforce_memory_limit(cmdline_memory_size);
-
-	/* Start with page aligned address of last symbol in kernel
-	 * image.
-	 */
-	start_pfn  = (unsigned long)__pa(PAGE_ALIGN((unsigned long) &_end));
-
-	/* Now shift down to get the real physical page frame number. */
-	start_pfn >>= PAGE_SHIFT;
-
-	max_pfn = end_of_phys_memory >> PAGE_SHIFT;
-
-	max_low_pfn = max_pfn;
-	highstart_pfn = highend_pfn = max_pfn;
-
-	if (max_low_pfn > pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT)) {
-		highstart_pfn = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
-		max_low_pfn = calc_max_low_pfn();
-		high_pages = calc_highpages();
-		printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
-		    high_pages >> (20 - PAGE_SHIFT));
-	}
-
-	find_ramdisk(end_of_phys_memory);
-
-	/* Reserve the kernel text/data/bss. */
-	size = (start_pfn << PAGE_SHIFT) - phys_base;
-	memblock_reserve(phys_base, size);
-	memblock_add(phys_base, size);
-
-	size = memblock_phys_mem_size() - memblock_reserved_size();
-	*pages_avail = (size >> PAGE_SHIFT) - high_pages;
-
-	/* Only allow low memory to be allocated via memblock allocation */
-	memblock_set_current_limit(max_low_pfn << PAGE_SHIFT);
-
-	return max_pfn;
-}
-
 /*
  * paging_init() sets up the page tables: We call the MMU specific
  * init routine based upon the Sun model type on the Sparc.
diff --git a/arch/sparc/mm/srmmu.c b/arch/sparc/mm/srmmu.c
index 3029527a5a9f..cf66a108b411 100644
--- a/arch/sparc/mm/srmmu.c
+++ b/arch/sparc/mm/srmmu.c
@@ -59,8 +59,6 @@ int vac_line_size;
 
 extern struct resource sparc_iomap;
 
-extern unsigned long last_valid_pfn;
-
 static pgd_t *srmmu_swapper_pg_dir;
 
 const struct sparc32_cachetlb_ops *sparc32_cachetlb_ops;
@@ -884,7 +882,6 @@ void __init srmmu_paging_init(void)
 	pud_t *pud;
 	pmd_t *pmd;
 	pte_t *pte;
-	unsigned long pages_avail;
 
 	init_mm.context = (unsigned long) NO_CONTEXT;
 	sparc_iomap.start = SUN4M_IOBASE_VADDR;	/* 16MB of IOSPACE on all sun4m's. */
@@ -910,9 +907,6 @@ void __init srmmu_paging_init(void)
 		prom_halt();
 	}
 
-	pages_avail = 0;
-	last_valid_pfn = bootmem_init(&pages_avail);
-
 	srmmu_nocache_calcsize();
 	srmmu_nocache_init();
 	srmmu_inherit_prom_mappings(0xfe400000, (LINUX_OPPROM_ENDVM - PAGE_SIZE));
-- 
2.43.0


^ permalink raw reply	[flat|nested] 7+ messages in thread

* [PATCH v2 6/6] sparc32: drop sp_banks
  2026-08-30 12:06 [PATCH v2 0/6] sparc32: replace sp_banks with memblock Magnus Lindholm
                   ` (4 preceding siblings ...)
  2026-08-30 12:06 ` [PATCH v2 5/6] sparc32: move early memory setup to setup_arch Magnus Lindholm
@ 2026-08-30 12:06 ` Magnus Lindholm
  5 siblings, 0 replies; 7+ messages in thread
From: Magnus Lindholm @ 2026-08-30 12:06 UTC (permalink / raw)
  To: sparclinux; +Cc: davem, andreas, linux-kernel, sam, glaubitz, Magnus Lindholm

All memory-map consumers now use memblock. Stop duplicating the PROM map
in sp_banks and remove the array, its type, and its fixed bank limit.

Suggested-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Magnus Lindholm <linmag7@gmail.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
---
 arch/sparc/include/asm/page_32.h | 16 -----------
 arch/sparc/mm/init_32.c          |  2 --
 arch/sparc/prom/memory.c         | 48 ++++----------------------------
 3 files changed, 6 insertions(+), 60 deletions(-)

diff --git a/arch/sparc/include/asm/page_32.h b/arch/sparc/include/asm/page_32.h
index c1bccbedf567..5daa5fd8eaa5 100644
--- a/arch/sparc/include/asm/page_32.h
+++ b/arch/sparc/include/asm/page_32.h
@@ -26,22 +26,6 @@
 		sparc_flush_page_to_ram(page);	\
 	} while (0)
 
-/* The following structure is used to hold the physical
- * memory configuration of the machine.  This is filled in
- * prom_meminit() and is later used by mem_init() to set up
- * mem_map[].  We statically allocate SPARC_PHYS_BANKS+1 of
- * these structs, this is arbitrary.  The entry after the
- * last valid one has num_bytes==0.
- */
-struct sparc_phys_banks {
-  unsigned long base_addr;
-  unsigned long num_bytes;
-};
-
-#define SPARC_PHYS_BANKS 32
-
-extern struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS+1];
-
 /* passing structs on the Sparc slow us down tremendously... */
 
 /* #define STRICT_MM_TYPECHECKS */
diff --git a/arch/sparc/mm/init_32.c b/arch/sparc/mm/init_32.c
index ac4462f1cf76..2f693b70dbd8 100644
--- a/arch/sparc/mm/init_32.c
+++ b/arch/sparc/mm/init_32.c
@@ -35,8 +35,6 @@
 
 #include "mm_32.h"
 
-struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS+1];
-
 /* Initial ramdisk setup */
 extern unsigned int sparc_ramdisk_image;
 extern unsigned int sparc_ramdisk_size;
diff --git a/arch/sparc/prom/memory.c b/arch/sparc/prom/memory.c
index 59962bc0bc82..3f65bde2bb89 100644
--- a/arch/sparc/prom/memory.c
+++ b/arch/sparc/prom/memory.c
@@ -8,30 +8,21 @@
 
 #include <linux/kernel.h>
 #include <linux/memblock.h>
-#include <linux/sort.h>
 #include <linux/init.h>
 
 #include <asm/openprom.h>
 #include <asm/oplib.h>
 #include <asm/page.h>
 
-static int __init prom_meminit_v0(void)
+static void __init prom_meminit_v0(void)
 {
 	struct linux_mlist_v0 *p;
-	int index;
 
-	index = 0;
-	for (p = *(romvec->pv_v0mem.v0_available); p; p = p->theres_more) {
-		sp_banks[index].base_addr = (unsigned long) p->start_adr;
-		sp_banks[index].num_bytes = p->num_bytes;
+	for (p = *(romvec->pv_v0mem.v0_available); p; p = p->theres_more)
 		memblock_add(p->start_adr, p->num_bytes & PAGE_MASK);
-		index++;
-	}
-
-	return index;
 }
 
-static int __init prom_meminit_v2(void)
+static void __init prom_meminit_v2(void)
 {
 	struct linux_prom_registers reg[64];
 	phandle node;
@@ -41,51 +32,24 @@ static int __init prom_meminit_v2(void)
 	size = prom_getproperty(node, "available", (char *) reg, sizeof(reg));
 	num_ents = size / sizeof(struct linux_prom_registers);
 
-	for (i = 0; i < num_ents; i++) {
-		sp_banks[i].base_addr = reg[i].phys_addr;
-		sp_banks[i].num_bytes = reg[i].reg_size;
+	for (i = 0; i < num_ents; i++)
 		memblock_add(reg[i].phys_addr, reg[i].reg_size & PAGE_MASK);
-	}
-
-	return num_ents;
-}
-
-static int sp_banks_cmp(const void *a, const void *b)
-{
-	const struct sparc_phys_banks *x = a, *y = b;
-
-	if (x->base_addr > y->base_addr)
-		return 1;
-	if (x->base_addr < y->base_addr)
-		return -1;
-	return 0;
 }
 
 /* Initialize the memory lists based upon the prom version. */
 void __init prom_meminit(void)
 {
-	int i, num_ents = 0;
-
 	switch (prom_vers) {
 	case PROM_V0:
-		num_ents = prom_meminit_v0();
+		prom_meminit_v0();
 		break;
 
 	case PROM_V2:
 	case PROM_V3:
-		num_ents = prom_meminit_v2();
+		prom_meminit_v2();
 		break;
 
 	default:
 		break;
 	}
-	sort(sp_banks, num_ents, sizeof(struct sparc_phys_banks),
-	     sp_banks_cmp, NULL);
-
-	/* Sentinel.  */
-	sp_banks[num_ents].base_addr = 0xdeadbeef;
-	sp_banks[num_ents].num_bytes = 0;
-
-	for (i = 0; i < num_ents; i++)
-		sp_banks[i].num_bytes &= PAGE_MASK;
 }
-- 
2.43.0


^ permalink raw reply	[flat|nested] 7+ messages in thread

end of thread, other threads:[~2026-08-30 12:08 UTC | newest]

Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2026-08-30 12:06 [PATCH v2 0/6] sparc32: replace sp_banks with memblock Magnus Lindholm
2026-08-30 12:06 ` [PATCH v2 1/6] sparc32: use memblock when mapping the kernel Magnus Lindholm
2026-08-30 12:06 ` [PATCH v2 2/6] sparc32: use memblock to find available system memory Magnus Lindholm
2026-08-30 12:06 ` [PATCH v2 3/6] sparc32: populate memblock from the PROM memory map Magnus Lindholm
2026-08-30 12:06 ` [PATCH v2 4/6] sparc32: drop unused valid address bitmap Magnus Lindholm
2026-08-30 12:06 ` [PATCH v2 5/6] sparc32: move early memory setup to setup_arch Magnus Lindholm
2026-08-30 12:06 ` [PATCH v2 6/6] sparc32: drop sp_banks Magnus Lindholm

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®