Blackfin arch: SMP supporting patchset: Blackfin kernel and memory management code
Blackfin dual core BF561 processor can support SMP like features.
https://docs.blackfin.uclinux.org/doku.php?id=linux-kernel:smp-like
In this patch, we provide SMP extend to Blackfin kernel and memory management code
Singed-off-by: Graf Yang <graf.yang@analog.com>
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
diff --git a/arch/blackfin/mm/init.c b/arch/blackfin/mm/init.c
index bc240ab..57d306b 100644
--- a/arch/blackfin/mm/init.c
+++ b/arch/blackfin/mm/init.c
@@ -31,7 +31,8 @@
#include <linux/bootmem.h>
#include <linux/uaccess.h>
#include <asm/bfin-global.h>
-#include <asm/l1layout.h>
+#include <asm/pda.h>
+#include <asm/cplbinit.h>
#include "blackfin_sram.h"
/*
@@ -53,6 +54,11 @@
unsigned long empty_zero_page;
+extern unsigned long exception_stack[NR_CPUS][1024];
+
+struct blackfin_pda cpu_pda[NR_CPUS];
+EXPORT_SYMBOL(cpu_pda);
+
/*
* paging_init() continues the virtual memory environment setup which
* was begun by the code in arch/head.S.
@@ -98,6 +104,42 @@
}
}
+asmlinkage void init_pda(void)
+{
+ unsigned int cpu = raw_smp_processor_id();
+
+ /* Initialize the PDA fields holding references to other parts
+ of the memory. The content of such memory is still
+ undefined at the time of the call, we are only setting up
+ valid pointers to it. */
+ memset(&cpu_pda[cpu], 0, sizeof(cpu_pda[cpu]));
+
+ cpu_pda[0].next = &cpu_pda[1];
+ cpu_pda[1].next = &cpu_pda[0];
+
+ cpu_pda[cpu].ex_stack = exception_stack[cpu + 1];
+
+#ifdef CONFIG_MPU
+#else
+ cpu_pda[cpu].ipdt = ipdt_tables[cpu];
+ cpu_pda[cpu].dpdt = dpdt_tables[cpu];
+#ifdef CONFIG_CPLB_INFO
+ cpu_pda[cpu].ipdt_swapcount = ipdt_swapcount_tables[cpu];
+ cpu_pda[cpu].dpdt_swapcount = dpdt_swapcount_tables[cpu];
+#endif
+#endif
+
+#ifdef CONFIG_SMP
+ cpu_pda[cpu].imask = 0x1f;
+#endif
+}
+
+void __cpuinit reserve_pda(void)
+{
+ printk(KERN_INFO "PDA for CPU%u reserved at %p\n", smp_processor_id(),
+ &cpu_pda[smp_processor_id()]);
+}
+
void __init mem_init(void)
{
unsigned int codek = 0, datak = 0, initk = 0;
@@ -141,21 +183,13 @@
static int __init sram_init(void)
{
- unsigned long tmp;
-
/* Initialize the blackfin L1 Memory. */
bfin_sram_init();
- /* Allocate this once; never free it. We assume this gives us a
- pointer to the start of L1 scratchpad memory; panic if it
- doesn't. */
- tmp = (unsigned long)l1sram_alloc(sizeof(struct l1_scratch_task_info));
- if (tmp != (unsigned long)L1_SCRATCH_TASK_INFO) {
- printk(KERN_EMERG "mem_init(): Did not get the right address from l1sram_alloc: %08lx != %08lx\n",
- tmp, (unsigned long)L1_SCRATCH_TASK_INFO);
- panic("No L1, time to give up\n");
- }
-
+ /* Reserve the PDA space for the boot CPU right after we
+ * initialized the scratch memory allocator.
+ */
+ reserve_pda();
return 0;
}
pure_initcall(sram_init);
