[PATCH v3 1/7] powerpc/8xx: Fix vaddr for IMMR early remap
From: Christophe Leroy
Date: Tue May 17 2016 - 03:02:58 EST
Memory: 124428K/131072K available (3748K kernel code, 188K rwdata,
648K rodata, 508K init, 290K bss, 6644K reserved)
Kernel virtual memory layout:
* 0xfffdf000..0xfffff000 : fixmap
* 0xfde00000..0xfe000000 : consistent mem
* 0xfddf6000..0xfde00000 : early ioremap
* 0xc9000000..0xfddf6000 : vmalloc & ioremap
SLUB: HWalign=16, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
Today, IMMR is mapped 1:1 at startup
Mapping IMMR 1:1 is just wrong because it may overlap with another
area. On most mpc8xx boards it is OK as IMMR is set to 0xff000000
but for instance on EP88xC board, IMMR is at 0xfa200000 which
overlaps with VM ioremap area
This patch fixes the virtual address for remapping IMMR with the fixmap
regardless of the value of IMMR.
The size of IMMR area is 256kbytes (CPM at offset 0, security engine
at offset 128k) so a 512k page is enough
Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>
---
v2: No change
v3: Fixed issue with EARLY_DEBUG on 82xx
arch/powerpc/include/asm/fixmap.h | 7 +++++++
arch/powerpc/include/asm/mmu-8xx.h | 3 +++
arch/powerpc/kernel/asm-offsets.c | 8 ++++++++
arch/powerpc/kernel/head_8xx.S | 11 ++++++-----
arch/powerpc/sysdev/cpm_common.c | 22 +++++++++++++++++-----
5 files changed, 41 insertions(+), 10 deletions(-)
diff --git a/arch/powerpc/include/asm/fixmap.h b/arch/powerpc/include/asm/fixmap.h
index 90f604b..4508b32 100644
--- a/arch/powerpc/include/asm/fixmap.h
+++ b/arch/powerpc/include/asm/fixmap.h
@@ -51,6 +51,13 @@ enum fixed_addresses {
FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */
FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1,
#endif
+#ifdef CONFIG_PPC_8xx
+ /* For IMMR we need an aligned 512K area */
+#define FIX_IMMR_SIZE (512 * 1024 / PAGE_SIZE)
+ FIX_IMMR_START,
+ FIX_IMMR_BASE = __ALIGN_MASK(FIX_IMMR_START, FIX_IMMR_SIZE - 1) - 1 +
+ FIX_IMMR_SIZE,
+#endif
/* FIX_PCIE_MCFG, */
__end_of_fixed_addresses
};
diff --git a/arch/powerpc/include/asm/mmu-8xx.h b/arch/powerpc/include/asm/mmu-8xx.h
index 0a566f1..3e0e492 100644
--- a/arch/powerpc/include/asm/mmu-8xx.h
+++ b/arch/powerpc/include/asm/mmu-8xx.h
@@ -169,6 +169,9 @@ typedef struct {
unsigned int active;
unsigned long vdso_base;
} mm_context_t;
+
+#define PHYS_IMMR_BASE (mfspr(SPRN_IMMR) & 0xfff80000)
+#define VIRT_IMMR_BASE (__fix_to_virt(FIX_IMMR_BASE))
#endif /* !__ASSEMBLY__ */
#if defined(CONFIG_PPC_4K_PAGES)
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 9ea0955..2652233 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -68,6 +68,10 @@
#include "../mm/mmu_decl.h"
#endif
+#ifdef CONFIG_PPC_8xx
+#include <asm/fixmap.h>
+#endif
+
int main(void)
{
DEFINE(THREAD, offsetof(struct task_struct, thread));
@@ -783,5 +787,9 @@ int main(void)
DEFINE(PPC_DBELL_SERVER, PPC_DBELL_SERVER);
+#ifdef CONFIG_PPC_8xx
+ DEFINE(VIRT_IMMR_BASE, __fix_to_virt(FIX_IMMR_BASE));
+#endif
+
return 0;
}
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 80c6947..378a185 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -30,6 +30,7 @@
#include <asm/ppc_asm.h>
#include <asm/asm-offsets.h>
#include <asm/ptrace.h>
+#include <asm/fixmap.h>
/* Macro to make the code more readable. */
#ifdef CONFIG_8xx_CPU6
@@ -763,7 +764,7 @@ start_here:
* virtual to physical. Also, set the cache mode since that is defined
* by TLB entries and perform any additional mapping (like of the IMMR).
* If configured to pin some TLBs, we pin the first 8 Mbytes of kernel,
- * 24 Mbytes of data, and the 8M IMMR space. Anything not covered by
+ * 24 Mbytes of data, and the 512k IMMR space. Anything not covered by
* these mappings is mapped by page tables.
*/
initial_mmu:
@@ -812,7 +813,7 @@ initial_mmu:
ori r8, r8, MD_APG_INIT@l
mtspr SPRN_MD_AP, r8
- /* Map another 8 MByte at the IMMR to get the processor
+ /* Map a 512k page for the IMMR to get the processor
* internal registers (among other things).
*/
#ifdef CONFIG_PIN_TLB
@@ -820,12 +821,12 @@ initial_mmu:
mtspr SPRN_MD_CTR, r10
#endif
mfspr r9, 638 /* Get current IMMR */
- andis. r9, r9, 0xff80 /* Get 8Mbyte boundary */
+ andis. r9, r9, 0xfff8 /* Get 512 kbytes boundary */
- mr r8, r9 /* Create vaddr for TLB */
+ lis r8, VIRT_IMMR_BASE@h /* Create vaddr for TLB */
ori r8, r8, MD_EVALID /* Mark it valid */
mtspr SPRN_MD_EPN, r8
- li r8, MD_PS8MEG /* Set 8M byte page */
+ li r8, MD_PS512K | MD_GUARDED /* Set 512k byte page */
ori r8, r8, MD_SVALID /* Make it valid */
mtspr SPRN_MD_TWC, r8
mr r8, r9 /* Create paddr for TLB */
diff --git a/arch/powerpc/sysdev/cpm_common.c b/arch/powerpc/sysdev/cpm_common.c
index 0ac12e5..911456d 100644
--- a/arch/powerpc/sysdev/cpm_common.c
+++ b/arch/powerpc/sysdev/cpm_common.c
@@ -28,6 +28,7 @@
#include <asm/udbg.h>
#include <asm/io.h>
#include <asm/cpm.h>
+#include <asm/fixmap.h>
#include <soc/fsl/qe/qe.h>
#include <mm/mmu_decl.h>
@@ -37,25 +38,36 @@
#endif
#ifdef CONFIG_PPC_EARLY_DEBUG_CPM
-static u32 __iomem *cpm_udbg_txdesc =
- (u32 __iomem __force *)CONFIG_PPC_EARLY_DEBUG_CPM_ADDR;
+static u32 __iomem *cpm_udbg_txdesc;
+static u8 __iomem *cpm_udbg_txbuf;
static void udbg_putc_cpm(char c)
{
- u8 __iomem *txbuf = (u8 __iomem __force *)in_be32(&cpm_udbg_txdesc[1]);
-
if (c == '\n')
udbg_putc_cpm('\r');
while (in_be32(&cpm_udbg_txdesc[0]) & 0x80000000)
;
- out_8(txbuf, c);
+ out_8(cpm_udbg_txbuf, c);
out_be32(&cpm_udbg_txdesc[0], 0xa0000001);
}
void __init udbg_init_cpm(void)
{
+#ifdef CONFIG_PPC_8xx
+ cpm_udbg_txdesc = (u32 __iomem __force *)
+ (CONFIG_PPC_EARLY_DEBUG_CPM_ADDR - PHYS_IMMR_BASE +
+ VIRT_IMMR_BASE);
+ cpm_udbg_txbuf = (u8 __iomem __force *)
+ (in_be32(&cpm_udbg_txdesc[1]) - PHYS_IMMR_BASE +
+ VIRT_IMMR_BASE);
+#else
+ cpm_udbg_txdesc = (u32 __iomem __force *)
+ CONFIG_PPC_EARLY_DEBUG_CPM_ADDR;
+ cpm_udbg_txbuf = (u8 __iomem __force *)in_be32(&cpm_udbg_txdesc[1]);
+#endif
+
if (cpm_udbg_txdesc) {
#ifdef CONFIG_CPM2
setbat(1, 0xf0000000, 0xf0000000, 1024*1024, PAGE_KERNEL_NCG);
--
2.1.0