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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/char/ipmi/ipmi_si_mem_io.c
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/char/ipmi/ipmi_si_mem_io.c')
-rw-r--r--drivers/char/ipmi/ipmi_si_mem_io.c146
1 files changed, 146 insertions, 0 deletions
diff --git a/drivers/char/ipmi/ipmi_si_mem_io.c b/drivers/char/ipmi/ipmi_si_mem_io.c
new file mode 100644
index 000000000..75583612a
--- /dev/null
+++ b/drivers/char/ipmi/ipmi_si_mem_io.c
@@ -0,0 +1,146 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+#include <linux/io.h>
+#include "ipmi_si.h"
+
+static unsigned char intf_mem_inb(const struct si_sm_io *io,
+ unsigned int offset)
+{
+ return readb((io->addr)+(offset * io->regspacing));
+}
+
+static void intf_mem_outb(const struct si_sm_io *io, unsigned int offset,
+ unsigned char b)
+{
+ writeb(b, (io->addr)+(offset * io->regspacing));
+}
+
+static unsigned char intf_mem_inw(const struct si_sm_io *io,
+ unsigned int offset)
+{
+ return (readw((io->addr)+(offset * io->regspacing)) >> io->regshift)
+ & 0xff;
+}
+
+static void intf_mem_outw(const struct si_sm_io *io, unsigned int offset,
+ unsigned char b)
+{
+ writeb(b << io->regshift, (io->addr)+(offset * io->regspacing));
+}
+
+static unsigned char intf_mem_inl(const struct si_sm_io *io,
+ unsigned int offset)
+{
+ return (readl((io->addr)+(offset * io->regspacing)) >> io->regshift)
+ & 0xff;
+}
+
+static void intf_mem_outl(const struct si_sm_io *io, unsigned int offset,
+ unsigned char b)
+{
+ writel(b << io->regshift, (io->addr)+(offset * io->regspacing));
+}
+
+#ifdef readq
+static unsigned char mem_inq(const struct si_sm_io *io, unsigned int offset)
+{
+ return (readq((io->addr)+(offset * io->regspacing)) >> io->regshift)
+ & 0xff;
+}
+
+static void mem_outq(const struct si_sm_io *io, unsigned int offset,
+ unsigned char b)
+{
+ writeq((u64)b << io->regshift, (io->addr)+(offset * io->regspacing));
+}
+#endif
+
+static void mem_region_cleanup(struct si_sm_io *io, int num)
+{
+ unsigned long addr = io->addr_data;
+ int idx;
+
+ for (idx = 0; idx < num; idx++)
+ release_mem_region(addr + idx * io->regspacing,
+ io->regsize);
+}
+
+static void mem_cleanup(struct si_sm_io *io)
+{
+ if (io->addr) {
+ iounmap(io->addr);
+ mem_region_cleanup(io, io->io_size);
+ }
+}
+
+int ipmi_si_mem_setup(struct si_sm_io *io)
+{
+ unsigned long addr = io->addr_data;
+ int mapsize, idx;
+
+ if (!addr)
+ return -ENODEV;
+
+ /*
+ * Figure out the actual readb/readw/readl/etc routine to use based
+ * upon the register size.
+ */
+ switch (io->regsize) {
+ case 1:
+ io->inputb = intf_mem_inb;
+ io->outputb = intf_mem_outb;
+ break;
+ case 2:
+ io->inputb = intf_mem_inw;
+ io->outputb = intf_mem_outw;
+ break;
+ case 4:
+ io->inputb = intf_mem_inl;
+ io->outputb = intf_mem_outl;
+ break;
+#ifdef readq
+ case 8:
+ io->inputb = mem_inq;
+ io->outputb = mem_outq;
+ break;
+#endif
+ default:
+ dev_warn(io->dev, "Invalid register size: %d\n",
+ io->regsize);
+ return -EINVAL;
+ }
+
+ /*
+ * Some BIOSes reserve disjoint memory regions in their ACPI
+ * tables. This causes problems when trying to request the
+ * entire region. Therefore we must request each register
+ * separately.
+ */
+ for (idx = 0; idx < io->io_size; idx++) {
+ if (request_mem_region(addr + idx * io->regspacing,
+ io->regsize, DEVICE_NAME) == NULL) {
+ /* Undo allocations */
+ mem_region_cleanup(io, idx);
+ return -EIO;
+ }
+ }
+
+ /*
+ * Calculate the total amount of memory to claim. This is an
+ * unusual looking calculation, but it avoids claiming any
+ * more memory than it has to. It will claim everything
+ * between the first address to the end of the last full
+ * register.
+ */
+ mapsize = ((io->io_size * io->regspacing)
+ - (io->regspacing - io->regsize));
+ io->addr = ioremap(addr, mapsize);
+ if (io->addr == NULL) {
+ mem_region_cleanup(io, io->io_size);
+ return -EIO;
+ }
+
+ io->io_cleanup = mem_cleanup;
+
+ return 0;
+}