[PATCH v2 07/21] ipmi: kcs_bmc: Make status update atomic

Andrew Jeffery
2021-03-19T06:27:38Z

Enable more efficient implementation of read-modify-write sequences.
Both device drivers for the KCS BMC stack use regmaps. The new callback
allows us to exploit regmap_update_bits().

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
---
drivers/char/ipmi/kcs_bmc.c | 7 +------
drivers/char/ipmi/kcs_bmc.h | 1 +
drivers/char/ipmi/kcs_bmc_aspeed.c | 9 +++++++++
drivers/char/ipmi/kcs_bmc_npcm7xx.c | 10 ++++++++++
4 files changed, 21 insertions(+), 6 deletions(-)

diff --git a/drivers/char/ipmi/kcs_bmc.c b/drivers/char/ipmi/kcs_bmc.c
index f292e74bd4a5..58fb1a7bd50d 100644
--- a/drivers/char/ipmi/kcs_bmc.c
+++ b/drivers/char/ipmi/kcs_bmc.c
@@ -67,12 +67,7 @@ static inline void write_status(struct kcs_bmc *kcs_bmc, u8 data)

static void update_status_bits(struct kcs_bmc *kcs_bmc, u8 mask, u8 val)
{
- u8 tmp = read_status(kcs_bmc);
-
- tmp &= ~mask;
- tmp |= val & mask;
-
- write_status(kcs_bmc, tmp);
+ kcs_bmc->io_updateb(kcs_bmc, kcs_bmc->ioreg.str, mask, val);
}

static inline void set_state(struct kcs_bmc *kcs_bmc, u8 state)
diff --git a/drivers/char/ipmi/kcs_bmc.h b/drivers/char/ipmi/kcs_bmc.h
index eb9ea4ce78b8..970f53892f2d 100644
--- a/drivers/char/ipmi/kcs_bmc.h
+++ b/drivers/char/ipmi/kcs_bmc.h
@@ -76,6 +76,7 @@ struct kcs_bmc {
struct kcs_ioreg ioreg;
u8 (*io_inputb)(struct kcs_bmc *kcs_bmc, u32 reg);
void (*io_outputb)(struct kcs_bmc *kcs_bmc, u32 reg, u8 b);
+ void (*io_updateb)(struct kcs_bmc *kcs_bmc, u32 reg, u8 mask, u8 val);

enum kcs_phases phase;
enum kcs_errors error;
diff --git a/drivers/char/ipmi/kcs_bmc_aspeed.c b/drivers/char/ipmi/kcs_bmc_aspeed.c
index 061f53676206..630cf095560e 100644
--- a/drivers/char/ipmi/kcs_bmc_aspeed.c
+++ b/drivers/char/ipmi/kcs_bmc_aspeed.c
@@ -90,6 +90,14 @@ static void aspeed_kcs_outb(struct kcs_bmc *kcs_bmc, u32 reg, u8 data)
WARN(rc != 0, "regmap_write() failed: %d\n", rc);
}

+static void aspeed_kcs_updateb(struct kcs_bmc *kcs_bmc, u32 reg, u8 mask, u8 val)
+{
+ struct aspeed_kcs_bmc *priv = kcs_bmc_priv(kcs_bmc);
+ int rc;
+
+ rc = regmap_update_bits(priv->map, reg, mask, val);
+ WARN(rc != 0, "regmap_update_bits() failed: %d\n", rc);
+}

/*
* AST_usrGuide_KCS.pdf
@@ -342,6 +350,7 @@ static int aspeed_kcs_probe(struct platform_device *pdev)
kcs_bmc->ioreg = ast_kcs_bmc_ioregs[channel - 1];
kcs_bmc->io_inputb = aspeed_kcs_inb;
kcs_bmc->io_outputb = aspeed_kcs_outb;
+ kcs_bmc->io_updateb = aspeed_kcs_updateb;

addr = ops->get_io_address(pdev);
if (addr < 0)
diff --git a/drivers/char/ipmi/kcs_bmc_npcm7xx.c b/drivers/char/ipmi/kcs_bmc_npcm7xx.c
index 722f7391fe1f..1f44aadec9e8 100644
--- a/drivers/char/ipmi/kcs_bmc_npcm7xx.c
+++ b/drivers/char/ipmi/kcs_bmc_npcm7xx.c
@@ -97,6 +97,15 @@ static void npcm7xx_kcs_outb(struct kcs_bmc *kcs_bmc, u32 reg, u8 data)
WARN(rc != 0, "regmap_write() failed: %d\n", rc);
}

+static void npcm7xx_kcs_updateb(struct kcs_bmc *kcs_bmc, u32 reg, u8 mask, u8 data)
+{
+ struct npcm7xx_kcs_bmc *priv = kcs_bmc_priv(kcs_bmc);
+ int rc;
+
+ rc = regmap_update_bits(priv->map, reg, mask, data);
+ WARN(rc != 0, "regmap_update_bits() failed: %d\n", rc);
+}
+
static void npcm7xx_kcs_enable_channel(struct kcs_bmc *kcs_bmc, bool enable)
{
struct npcm7xx_kcs_bmc *priv = kcs_bmc_priv(kcs_bmc);
@@ -163,6 +172,7 @@ static int npcm7xx_kcs_probe(struct platform_device *pdev)
kcs_bmc->ioreg.str = priv->reg->sts;
kcs_bmc->io_inputb = npcm7xx_kcs_inb;
kcs_bmc->io_outputb = npcm7xx_kcs_outb;
+ kcs_bmc->io_updateb = npcm7xx_kcs_updateb;

dev_set_drvdata(dev, kcs_bmc);

--
2.27.0