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Diffstat (limited to 'arch/riscv/mm/init.c')
-rw-r--r--arch/riscv/mm/init.c93
1 files changed, 86 insertions, 7 deletions
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index c07ff3e2c90a..943c18d6ef4d 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -1299,6 +1299,28 @@ static inline void setup_vm_final(void)
}
#endif /* CONFIG_MMU */
+/* Reserve 128M low memory by default for swiotlb buffer */
+#define DEFAULT_CRASH_KERNEL_LOW_SIZE (128UL << 20)
+
+static int __init reserve_crashkernel_low(unsigned long long low_size)
+{
+ unsigned long long low_base;
+
+ low_base = memblock_phys_alloc_range(low_size, PMD_SIZE, 0, dma32_phys_limit);
+ if (!low_base) {
+ pr_err("cannot allocate crashkernel low memory (size:0x%llx).\n", low_size);
+ return -ENOMEM;
+ }
+
+ pr_info("crashkernel low memory reserved: 0x%016llx - 0x%016llx (%lld MB)\n",
+ low_base, low_base + low_size, low_size >> 20);
+
+ crashk_low_res.start = low_base;
+ crashk_low_res.end = low_base + low_size - 1;
+
+ return 0;
+}
+
/*
* reserve_crashkernel() - reserves memory for crash kernel
*
@@ -1310,8 +1332,12 @@ static void __init reserve_crashkernel(void)
{
unsigned long long crash_base = 0;
unsigned long long crash_size = 0;
+ unsigned long long crash_low_size = 0;
unsigned long search_start = memblock_start_of_DRAM();
- unsigned long search_end = memblock_end_of_DRAM();
+ unsigned long search_end = (unsigned long)dma32_phys_limit;
+ char *cmdline = boot_command_line;
+ bool fixed_base = false;
+ bool high = false;
int ret = 0;
@@ -1327,14 +1353,36 @@ static void __init reserve_crashkernel(void)
return;
}
- ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(),
+ ret = parse_crashkernel(cmdline, memblock_phys_mem_size(),
&crash_size, &crash_base);
- if (ret || !crash_size)
+ if (ret == -ENOENT) {
+ /* Fallback to crashkernel=X,[high,low] */
+ ret = parse_crashkernel_high(cmdline, 0, &crash_size, &crash_base);
+ if (ret || !crash_size)
+ return;
+
+ /*
+ * crashkernel=Y,low is valid only when crashkernel=X,high
+ * is passed.
+ */
+ ret = parse_crashkernel_low(cmdline, 0, &crash_low_size, &crash_base);
+ if (ret == -ENOENT)
+ crash_low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE;
+ else if (ret)
+ return;
+
+ search_start = (unsigned long)dma32_phys_limit;
+ search_end = memblock_end_of_DRAM();
+ high = true;
+ } else if (ret || !crash_size) {
+ /* Invalid argument value specified */
return;
+ }
crash_size = PAGE_ALIGN(crash_size);
if (crash_base) {
+ fixed_base = true;
search_start = crash_base;
search_end = crash_base + crash_size;
}
@@ -1347,12 +1395,37 @@ static void __init reserve_crashkernel(void)
* swiotlb can work on the crash kernel.
*/
crash_base = memblock_phys_alloc_range(crash_size, PMD_SIZE,
- search_start,
- min(search_end, (unsigned long)(SZ_4G - 1)));
+ search_start, search_end);
if (crash_base == 0) {
- /* Try again without restricting region to 32bit addressible memory */
+ /*
+ * For crashkernel=size[KMG]@offset[KMG], print out failure
+ * message if can't reserve the specified region.
+ */
+ if (fixed_base) {
+ pr_warn("crashkernel: allocating failed with given size@offset\n");
+ return;
+ }
+
+ if (high) {
+ /*
+ * For crashkernel=size[KMG],high, if the first attempt was
+ * for high memory, fall back to low memory.
+ */
+ search_start = memblock_start_of_DRAM();
+ search_end = (unsigned long)dma32_phys_limit;
+ } else {
+ /*
+ * For crashkernel=size[KMG], if the first attempt was for
+ * low memory, fall back to high memory, the minimum required
+ * low memory will be reserved later.
+ */
+ search_start = (unsigned long)dma32_phys_limit;
+ search_end = memblock_end_of_DRAM();
+ crash_low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE;
+ }
+
crash_base = memblock_phys_alloc_range(crash_size, PMD_SIZE,
- search_start, search_end);
+ search_start, search_end);
if (crash_base == 0) {
pr_warn("crashkernel: couldn't allocate %lldKB\n",
crash_size >> 10);
@@ -1360,6 +1433,12 @@ static void __init reserve_crashkernel(void)
}
}
+ if ((crash_base >= dma32_phys_limit) && crash_low_size &&
+ reserve_crashkernel_low(crash_low_size)) {
+ memblock_phys_free(crash_base, crash_size);
+ return;
+ }
+
pr_info("crashkernel: reserved 0x%016llx - 0x%016llx (%lld MB)\n",
crash_base, crash_base + crash_size, crash_size >> 20);