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Message-Id: <20220816130823.97903-2-linus.walleij@linaro.org>
Date: Tue, 16 Aug 2022 15:08:23 +0200
From: Linus Walleij <linus.walleij@...aro.org>
To: Mark Brown <broonie@...nel.org>
Cc: linux-kernel@...r.kernel.org,
Linus Walleij <linus.walleij@...aro.org>
Subject: [PATCH 2/2 v3] regmap: mmio: Support accelerared noinc operations
Use the newly added callback for accelerated noinc MMIO
to provide writesb, writesw, writesl, writesq, readsb, readsw,
readsl and readsq.
A special quirk is needed to deal with big endian regmaps: there
are no accelerated operations defined for big endian, so fall
back to calling the big endian operations itereatively for this
case.
Signed-off-by: Linus Walleij <linus.walleij@...aro.org>
---
ChangeLog v2->v3:
- Rebase on kernel v6.0-rc1
ChangeLog v1->v2:
- No changes.
---
drivers/base/regmap/regmap-mmio.c | 153 ++++++++++++++++++++++++++++++
1 file changed, 153 insertions(+)
diff --git a/drivers/base/regmap/regmap-mmio.c b/drivers/base/regmap/regmap-mmio.c
index 71f16be7e717..031ee91020e8 100644
--- a/drivers/base/regmap/regmap-mmio.c
+++ b/drivers/base/regmap/regmap-mmio.c
@@ -17,6 +17,7 @@ struct regmap_mmio_context {
void __iomem *regs;
unsigned int val_bytes;
bool relaxed_mmio;
+ bool big_endian;
bool attached_clk;
struct clk *clk;
@@ -160,6 +161,79 @@ static int regmap_mmio_write(void *context, unsigned int reg, unsigned int val)
return 0;
}
+static int regmap_mmio_noinc_write(void *context, unsigned int reg,
+ const void *val, size_t val_count)
+{
+ struct regmap_mmio_context *ctx = context;
+ int ret = 0;
+ int i;
+
+ if (!IS_ERR(ctx->clk)) {
+ ret = clk_enable(ctx->clk);
+ if (ret < 0)
+ return ret;
+ }
+
+ /*
+ * There are no native, assembly-optimized write single register
+ * operations for big endian, so fall back to emulation if this
+ * is needed. (Single bytes are fine, they are not affected by
+ * endianness.)
+ */
+ if (ctx->big_endian && (ctx->val_bytes > 1)) {
+ switch (ctx->val_bytes) {
+ case 2:
+ {
+ const u16 *valp = (const u16 *)val;
+ for (i = 0; i < val_count; i++)
+ iowrite16be(valp[i], ctx->regs + reg);
+ break;
+ }
+ case 4:
+ {
+ const u32 *valp = (const u32 *)val;
+ for (i = 0; i < val_count; i++)
+ iowrite32be(valp[i], ctx->regs + reg);
+ break;
+ }
+#ifdef CONFIG_64BIT
+ case 8:
+ /* This is just too esoteric */
+ fallthrough;
+#endif
+ default:
+ ret = -EINVAL;
+ goto out_clk;
+ }
+ }
+
+ switch (ctx->val_bytes) {
+ case 1:
+ writesb(ctx->regs + reg, (const u8 *)val, val_count);
+ break;
+ case 2:
+ writesw(ctx->regs + reg, (const u16 *)val, val_count);
+ break;
+ case 4:
+ writesl(ctx->regs + reg, (const u32 *)val, val_count);
+ break;
+#ifdef CONFIG_64BIT
+ case 8:
+ writesq(ctx->regs + reg, (const u64 *)val, val_count);
+ break;
+#endif
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+out_clk:
+ if (!IS_ERR(ctx->clk))
+ clk_disable(ctx->clk);
+
+ return ret;
+}
+
static unsigned int regmap_mmio_read8(struct regmap_mmio_context *ctx,
unsigned int reg)
{
@@ -241,6 +315,82 @@ static int regmap_mmio_read(void *context, unsigned int reg, unsigned int *val)
return 0;
}
+static int regmap_mmio_noinc_read(void *context, unsigned int reg,
+ void *val, size_t val_count)
+{
+ struct regmap_mmio_context *ctx = context;
+ int ret = 0;
+ int i;
+
+ if (!IS_ERR(ctx->clk)) {
+ ret = clk_enable(ctx->clk);
+ if (ret < 0)
+ return ret;
+ }
+
+ /*
+ * There are no native, assembly-optimized write single register
+ * operations for big endian, so fall back to emulation if this
+ * is needed. (Single bytes are fine, they are not affected by
+ * endianness.)
+ */
+ if (ctx->big_endian && (ctx->val_bytes > 1)) {
+ switch (ctx->val_bytes) {
+ case 2:
+ {
+ u16 *valp = (u16 *)val;
+ for (i = 0; i < val_count; i++)
+ valp[i] = ioread16be(ctx->regs + reg);
+ break;
+ }
+ case 4:
+ {
+ u32 *valp = (u32 *)val;
+ for (i = 0; i < val_count; i++)
+ valp[i] = ioread32be(ctx->regs + reg);
+ break;
+ }
+#ifdef CONFIG_64BIT
+ case 8:
+ /* This is just too esoteric */
+ fallthrough;
+#endif
+ default:
+ ret = -EINVAL;
+ goto out_clk;
+ }
+ }
+
+ switch (ctx->val_bytes) {
+ case 1:
+ readsb(ctx->regs + reg, (u8 *)val, val_count);
+ break;
+ case 2:
+ readsw(ctx->regs + reg, (u16 *)val, val_count);
+ break;
+ case 4:
+ readsl(ctx->regs + reg, (u32 *)val, val_count);
+ break;
+#ifdef CONFIG_64BIT
+ case 8:
+ readsq(ctx->regs + reg, (u64 *)val, val_count);
+ break;
+#endif
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+out_clk:
+ if (!IS_ERR(ctx->clk))
+ clk_disable(ctx->clk);
+
+ return ret;
+
+ return 0;
+}
+
+
static void regmap_mmio_free_context(void *context)
{
struct regmap_mmio_context *ctx = context;
@@ -257,6 +407,8 @@ static const struct regmap_bus regmap_mmio = {
.fast_io = true,
.reg_write = regmap_mmio_write,
.reg_read = regmap_mmio_read,
+ .reg_noinc_write = regmap_mmio_noinc_write,
+ .reg_noinc_read = regmap_mmio_noinc_read,
.free_context = regmap_mmio_free_context,
.val_format_endian_default = REGMAP_ENDIAN_LITTLE,
};
@@ -347,6 +499,7 @@ static struct regmap_mmio_context *regmap_mmio_gen_context(struct device *dev,
#ifdef __BIG_ENDIAN
case REGMAP_ENDIAN_NATIVE:
#endif
+ ctx->big_endian = true;
switch (config->val_bits) {
case 8:
ctx->reg_read = regmap_mmio_read8;
--
2.37.2
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