aboutsummaryrefslogtreecommitdiffstats
path: root/arch/sh/mm/ioremap.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2020-08-15 18:50:32 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-08-15 18:50:32 -0700
commit5bbec3cfe376ed0014d9456a9be11d5ed75d587b (patch)
tree6f08b9135f85ca501bc5f22d75135b23ddf616e8 /arch/sh/mm/ioremap.c
parentMerge tag 'perf-tools-2020-08-14' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux (diff)
parentsh: landisk: Add missing initialization of sh_io_port_base (diff)
downloadlinux-dev-5bbec3cfe376ed0014d9456a9be11d5ed75d587b.tar.xz
linux-dev-5bbec3cfe376ed0014d9456a9be11d5ed75d587b.zip
Merge tag 'sh-for-5.9' of git://git.libc.org/linux-sh
Pull arch/sh updates from Rich Felker: "Cleanup, SECCOMP_FILTER support, message printing fixes, and other changes to arch/sh" * tag 'sh-for-5.9' of git://git.libc.org/linux-sh: (34 commits) sh: landisk: Add missing initialization of sh_io_port_base sh: bring syscall_set_return_value in line with other architectures sh: Add SECCOMP_FILTER sh: Rearrange blocks in entry-common.S sh: switch to copy_thread_tls() sh: use the generic dma coherent remap allocator sh: don't allow non-coherent DMA for NOMMU dma-mapping: consolidate the NO_DMA definition in kernel/dma/Kconfig sh: unexport register_trapped_io and match_trapped_io_handler sh: don't include <asm/io_trapped.h> in <asm/io.h> sh: move the ioremap implementation out of line sh: move ioremap_fixed details out of <asm/io.h> sh: remove __KERNEL__ ifdefs from non-UAPI headers sh: sort the selects for SUPERH alphabetically sh: remove -Werror from Makefiles sh: Replace HTTP links with HTTPS ones arch/sh/configs: remove obsolete CONFIG_SOC_CAMERA* sh: stacktrace: Remove stacktrace_ops.stack() sh: machvec: Modernize printing of kernel messages sh: pci: Modernize printing of kernel messages ...
Diffstat (limited to 'arch/sh/mm/ioremap.c')
-rw-r--r--arch/sh/mm/ioremap.c55
1 files changed, 55 insertions, 0 deletions
diff --git a/arch/sh/mm/ioremap.c b/arch/sh/mm/ioremap.c
index f6d02246d665..21342581144d 100644
--- a/arch/sh/mm/ioremap.c
+++ b/arch/sh/mm/ioremap.c
@@ -18,12 +18,59 @@
#include <linux/mm.h>
#include <linux/pci.h>
#include <linux/io.h>
+#include <asm/io_trapped.h>
#include <asm/page.h>
#include <asm/pgalloc.h>
#include <asm/addrspace.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>
#include <asm/mmu.h>
+#include "ioremap.h"
+
+/*
+ * On 32-bit SH, we traditionally have the whole physical address space mapped
+ * at all times (as MIPS does), so "ioremap()" and "iounmap()" do not need to do
+ * anything but place the address in the proper segment. This is true for P1
+ * and P2 addresses, as well as some P3 ones. However, most of the P3 addresses
+ * and newer cores using extended addressing need to map through page tables, so
+ * the ioremap() implementation becomes a bit more complicated.
+ */
+#ifdef CONFIG_29BIT
+static void __iomem *
+__ioremap_29bit(phys_addr_t offset, unsigned long size, pgprot_t prot)
+{
+ phys_addr_t last_addr = offset + size - 1;
+
+ /*
+ * For P1 and P2 space this is trivial, as everything is already
+ * mapped. Uncached access for P1 addresses are done through P2.
+ * In the P3 case or for addresses outside of the 29-bit space,
+ * mapping must be done by the PMB or by using page tables.
+ */
+ if (likely(PXSEG(offset) < P3SEG && PXSEG(last_addr) < P3SEG)) {
+ u64 flags = pgprot_val(prot);
+
+ /*
+ * Anything using the legacy PTEA space attributes needs
+ * to be kicked down to page table mappings.
+ */
+ if (unlikely(flags & _PAGE_PCC_MASK))
+ return NULL;
+ if (unlikely(flags & _PAGE_CACHABLE))
+ return (void __iomem *)P1SEGADDR(offset);
+
+ return (void __iomem *)P2SEGADDR(offset);
+ }
+
+ /* P4 above the store queues are always mapped. */
+ if (unlikely(offset >= P3_ADDR_MAX))
+ return (void __iomem *)P4SEGADDR(offset);
+
+ return NULL;
+}
+#else
+#define __ioremap_29bit(offset, size, prot) NULL
+#endif /* CONFIG_29BIT */
/*
* Remap an arbitrary physical address space into the kernel virtual
@@ -42,6 +89,14 @@ __ioremap_caller(phys_addr_t phys_addr, unsigned long size,
unsigned long offset, last_addr, addr, orig_addr;
void __iomem *mapped;
+ mapped = __ioremap_trapped(phys_addr, size);
+ if (mapped)
+ return mapped;
+
+ mapped = __ioremap_29bit(phys_addr, size, pgprot);
+ if (mapped)
+ return mapped;
+
/* Don't allow wraparound or zero size */
last_addr = phys_addr + size - 1;
if (!size || last_addr < phys_addr)