[PATCH v2 11/11] xtensa: mm: Convert to GENERIC_IOREMAP

From: Baoquan He
Date: Fri Aug 19 2022 - 20:32:55 EST


Add hooks arch_ioremap() and arch_iounmap() for xtensa's special
operation when ioremap() and iounmap(). Then define and implement its
own ioremap() and ioremap_cache().

Signed-off-by: Baoquan He <bhe@xxxxxxxxxx>
Cc: Chris Zankel <chris@xxxxxxxxxx>
Cc: Max Filippov <jcmvbkbc@xxxxxxxxx>
Cc: linux-xtensa@xxxxxxxxxxxxxxxx
---
arch/xtensa/Kconfig | 1 +
arch/xtensa/include/asm/io.h | 39 +++++++++++--------------
arch/xtensa/mm/ioremap.c | 56 +++++++++---------------------------
3 files changed, 31 insertions(+), 65 deletions(-)

diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
index 12ac277282ba..ee3a638f5458 100644
--- a/arch/xtensa/Kconfig
+++ b/arch/xtensa/Kconfig
@@ -29,6 +29,7 @@ config XTENSA
select GENERIC_LIB_UCMPDI2
select GENERIC_PCI_IOMAP
select GENERIC_SCHED_CLOCK
+ select GENERIC_IOREMAP if MMU
select HAVE_ARCH_AUDITSYSCALL
select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL
select HAVE_ARCH_KASAN if MMU && !XIP_KERNEL
diff --git a/arch/xtensa/include/asm/io.h b/arch/xtensa/include/asm/io.h
index a5b707e1c0f4..04dfc0dc936b 100644
--- a/arch/xtensa/include/asm/io.h
+++ b/arch/xtensa/include/asm/io.h
@@ -16,6 +16,7 @@
#include <asm/vectors.h>
#include <linux/bug.h>
#include <linux/kernel.h>
+#include <linux/pgtable.h>

#include <linux/types.h>

@@ -23,23 +24,29 @@
#define IO_SPACE_LIMIT ~0
#define PCI_IOBASE ((void __iomem *)XCHAL_KIO_BYPASS_VADDR)

-#ifdef CONFIG_MMU
-
-void __iomem *xtensa_ioremap_nocache(unsigned long addr, unsigned long size);
-void __iomem *xtensa_ioremap_cache(unsigned long addr, unsigned long size);
-void xtensa_iounmap(volatile void __iomem *addr);
-
/*
- * Return the virtual address for the specified bus memory.
+ * I/O memory mapping functions.
*/
+void __iomem *
+arch_ioremap(phys_addr_t *paddr, size_t size, unsigned long *prot_val);
+#define arch_ioremap arch_ioremap
+
+int arch_iounmap(void __iomem *addr);
+#define arch_iounmap arch_iounmap
+
+void __iomem *ioremap_prot(phys_addr_t paddr, size_t size,
+ unsigned long prot);
+
static inline void __iomem *ioremap(unsigned long offset, unsigned long size)
{
if (offset >= XCHAL_KIO_PADDR
&& offset - XCHAL_KIO_PADDR < XCHAL_KIO_SIZE)
return (void*)(offset-XCHAL_KIO_PADDR+XCHAL_KIO_BYPASS_VADDR);
else
- return xtensa_ioremap_nocache(offset, size);
+ return ioremap_prot(offset, size,
+ pgprot_val(pgprot_noncached(PAGE_KERNEL)));
}
+#define ioremap ioremap

static inline void __iomem *ioremap_cache(unsigned long offset,
unsigned long size)
@@ -48,22 +55,10 @@ static inline void __iomem *ioremap_cache(unsigned long offset,
&& offset - XCHAL_KIO_PADDR < XCHAL_KIO_SIZE)
return (void*)(offset-XCHAL_KIO_PADDR+XCHAL_KIO_CACHED_VADDR);
else
- return xtensa_ioremap_cache(offset, size);
-}
-#define ioremap_cache ioremap_cache
-
-static inline void iounmap(volatile void __iomem *addr)
-{
- unsigned long va = (unsigned long) addr;
+ return ioremap_prot(offset, size, pgprot_val(PAGE_KERNEL));

- if (!(va >= XCHAL_KIO_CACHED_VADDR &&
- va - XCHAL_KIO_CACHED_VADDR < XCHAL_KIO_SIZE) &&
- !(va >= XCHAL_KIO_BYPASS_VADDR &&
- va - XCHAL_KIO_BYPASS_VADDR < XCHAL_KIO_SIZE))
- xtensa_iounmap(addr);
}
-
-#endif /* CONFIG_MMU */
+#define ioremap_cache ioremap_cache

#include <asm-generic/io.h>

diff --git a/arch/xtensa/mm/ioremap.c b/arch/xtensa/mm/ioremap.c
index a400188c16b9..0508448d767a 100644
--- a/arch/xtensa/mm/ioremap.c
+++ b/arch/xtensa/mm/ioremap.c
@@ -6,60 +6,30 @@
*/

#include <linux/io.h>
-#include <linux/vmalloc.h>
#include <linux/pgtable.h>
#include <asm/cacheflush.h>
#include <asm/io.h>

-static void __iomem *xtensa_ioremap(unsigned long paddr, unsigned long size,
- pgprot_t prot)
+void __iomem *
+arch_ioremap(phys_addr_t *paddr, size_t size, unsigned long *prot_val)
{
- unsigned long offset = paddr & ~PAGE_MASK;
- unsigned long pfn = __phys_to_pfn(paddr);
- struct vm_struct *area;
- unsigned long vaddr;
- int err;
-
- paddr &= PAGE_MASK;
+ unsigned long phys_addr = *paddr;
+ unsigned long pfn = __phys_to_pfn(phys_addr);

WARN_ON(pfn_valid(pfn));

- size = PAGE_ALIGN(offset + size);
-
- area = get_vm_area(size, VM_IOREMAP);
- if (!area)
- return NULL;
-
- vaddr = (unsigned long)area->addr;
- area->phys_addr = paddr;
-
- err = ioremap_page_range(vaddr, vaddr + size, paddr, prot);
-
- if (err) {
- vunmap((void *)vaddr);
- return NULL;
- }
-
- flush_cache_vmap(vaddr, vaddr + size);
- return (void __iomem *)(offset + vaddr);
+ return NULL;
}

-void __iomem *xtensa_ioremap_nocache(unsigned long addr, unsigned long size)
+int arch_iounmap(void __iomem *addr)
{
- return xtensa_ioremap(addr, size, pgprot_noncached(PAGE_KERNEL));
-}
-EXPORT_SYMBOL(xtensa_ioremap_nocache);
+ unsigned long va = (unsigned long) addr;

-void __iomem *xtensa_ioremap_cache(unsigned long addr, unsigned long size)
-{
- return xtensa_ioremap(addr, size, PAGE_KERNEL);
-}
-EXPORT_SYMBOL(xtensa_ioremap_cache);
-
-void xtensa_iounmap(volatile void __iomem *io_addr)
-{
- void *addr = (void *)(PAGE_MASK & (unsigned long)io_addr);
+ if ((va >= XCHAL_KIO_CACHED_VADDR &&
+ va - XCHAL_KIO_CACHED_VADDR < XCHAL_KIO_SIZE) ||
+ (va >= XCHAL_KIO_BYPASS_VADDR &&
+ va - XCHAL_KIO_BYPASS_VADDR < XCHAL_KIO_SIZE))
+ return -EINVAL;

- vunmap(addr);
+ return 0;
}
-EXPORT_SYMBOL(xtensa_iounmap);
--
2.34.1