[PATCH v2] clk: qcom: clk-rpmh: Add IPA clock support

From: David Dai
Date: Thu Jan 24 2019 - 19:47:12 EST


The clk-rpmh driver only supports on and off RPMh clock resources. Let's
extend the driver by adding support for clocks that are managed by a
different type of RPMh resource known as Bus Clock Manager(BCM). The BCM
is a configurable shared resource aggregator that scales performance
based on a set of frequency points. The Qualcomm IP Accelerator (IPA)
clock is an example of a resource that is managed by the BCM and this a
requirement from the IPA driver in order to scale its core clock.

Signed-off-by: David Dai <daidavid1@xxxxxxxxxxxxxx>
---
drivers/clk/qcom/clk-rpmh.c | 146 ++++++++++++++++++++++++++++++++++
include/dt-bindings/clock/qcom,rpmh.h | 1 +
2 files changed, 147 insertions(+)

diff --git a/drivers/clk/qcom/clk-rpmh.c b/drivers/clk/qcom/clk-rpmh.c
index 9f4fc77..c3fd632 100644
--- a/drivers/clk/qcom/clk-rpmh.c
+++ b/drivers/clk/qcom/clk-rpmh.c
@@ -18,6 +18,31 @@
#define CLK_RPMH_ARC_EN_OFFSET 0
#define CLK_RPMH_VRM_EN_OFFSET 4

+#define BCM_TCS_CMD_COMMIT_MASK 0x40000000
+#define BCM_TCS_CMD_VALID_SHIFT 29
+#define BCM_TCS_CMD_VOTE_MASK 0x3fff
+#define BCM_TCS_CMD_VOTE_SHIFT 0
+
+#define BCM_TCS_CMD(valid, vote) \
+ (BCM_TCS_CMD_COMMIT_MASK | \
+ ((valid) << BCM_TCS_CMD_VALID_SHIFT) | \
+ ((vote & BCM_TCS_CMD_VOTE_MASK) \
+ << BCM_TCS_CMD_VOTE_SHIFT))
+
+/**
+ * struct bcm_db - Auxiliary data pertaining to each Bus Clock Manager(BCM)
+ * @unit: divisor used to convert Hz value to an RPMh msg
+ * @width: multiplier used to convert Hz value to an RPMh msg
+ * @vcd: virtual clock domain that this bcm belongs to
+ * @reserved: reserved to pad the struct
+ */
+struct bcm_db {
+ __le32 unit;
+ __le16 width;
+ u8 vcd;
+ u8 reserved;
+};
+
/**
* struct clk_rpmh - individual rpmh clock data structure
* @hw: handle between common and hardware-specific interfaces
@@ -29,6 +54,7 @@
* @aggr_state: rpmh clock aggregated state
* @last_sent_aggr_state: rpmh clock last aggr state sent to RPMh
* @valid_state_mask: mask to determine the state of the rpmh clock
+ * @unit: divisor to convert rate to rpmh msg in magnitudes of Khz
* @dev: device to which it is attached
* @peer: pointer to the clock rpmh sibling
*/
@@ -42,6 +68,7 @@ struct clk_rpmh {
u32 aggr_state;
u32 last_sent_aggr_state;
u32 valid_state_mask;
+ u32 unit;
struct device *dev;
struct clk_rpmh *peer;
};
@@ -98,6 +125,17 @@ struct clk_rpmh_desc {
__DEFINE_CLK_RPMH(_platform, _name, _name_active, _res_name, \
CLK_RPMH_VRM_EN_OFFSET, 1, _div)

+#define DEFINE_CLK_RPMH_BCM(_platform, _name, _res_name) \
+ static struct clk_rpmh _platform##_##_name = { \
+ .res_name = _res_name, \
+ .valid_state_mask = BIT(RPMH_ACTIVE_ONLY_STATE), \
+ .div = 1, \
+ .hw.init = &(struct clk_init_data){ \
+ .ops = &clk_rpmh_bcm_ops, \
+ .name = #_name, \
+ }, \
+ }
+
static inline struct clk_rpmh *to_clk_rpmh(struct clk_hw *_hw)
{
return container_of(_hw, struct clk_rpmh, hw);
@@ -210,6 +248,96 @@ static unsigned long clk_rpmh_recalc_rate(struct clk_hw *hw,
.recalc_rate = clk_rpmh_recalc_rate,
};

+static int clk_rpmh_bcm_send_cmd(struct clk_rpmh *c, bool enable)
+{
+ struct tcs_cmd cmd = { 0 };
+ u32 cmd_state;
+ int ret;
+
+ mutex_lock(&rpmh_clk_lock);
+
+ cmd_state = 0;
+ if (enable) {
+ cmd_state = 1;
+ if (c->aggr_state)
+ cmd_state = c->aggr_state;
+ }
+
+ if (c->last_sent_aggr_state == cmd_state) {
+ mutex_unlock(&rpmh_clk_lock);
+ return 0;
+ }
+
+ cmd.addr = c->res_addr;
+ cmd.data = BCM_TCS_CMD(enable, cmd_state);
+
+ ret = rpmh_write_async(c->dev, RPMH_ACTIVE_ONLY_STATE, &cmd, 1);
+ if (ret) {
+ dev_err(c->dev, "set active state of %s failed: (%d)\n",
+ c->res_name, ret);
+ mutex_unlock(&rpmh_clk_lock);
+ return ret;
+ }
+
+ c->last_sent_aggr_state = cmd_state;
+
+ mutex_unlock(&rpmh_clk_lock);
+
+ return 0;
+}
+
+static int clk_rpmh_bcm_prepare(struct clk_hw *hw)
+{
+ struct clk_rpmh *c = to_clk_rpmh(hw);
+
+ return clk_rpmh_bcm_send_cmd(c, true);
+};
+
+static void clk_rpmh_bcm_unprepare(struct clk_hw *hw)
+{
+ struct clk_rpmh *c = to_clk_rpmh(hw);
+
+ clk_rpmh_bcm_send_cmd(c, false);
+};
+
+static int clk_rpmh_bcm_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct clk_rpmh *c = to_clk_rpmh(hw);
+
+ c->aggr_state = rate / c->unit;
+ /*
+ * Since any non-zero value sent to hw would result in enabling the
+ * clock, only send the value if the clock has already been prepared.
+ */
+ if (clk_hw_is_prepared(hw))
+ clk_rpmh_bcm_send_cmd(c, true);
+
+ return 0;
+};
+
+static long clk_rpmh_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *parent_rate)
+{
+ return rate;
+}
+
+static unsigned long clk_rpmh_bcm_recalc_rate(struct clk_hw *hw,
+ unsigned long prate)
+{
+ struct clk_rpmh *c = to_clk_rpmh(hw);
+
+ return c->aggr_state * c->unit;
+}
+
+static const struct clk_ops clk_rpmh_bcm_ops = {
+ .prepare = clk_rpmh_bcm_prepare,
+ .unprepare = clk_rpmh_bcm_unprepare,
+ .set_rate = clk_rpmh_bcm_set_rate,
+ .round_rate = clk_rpmh_round_rate,
+ .recalc_rate = clk_rpmh_bcm_recalc_rate,
+};
+
/* Resource name must match resource id present in cmd-db. */
DEFINE_CLK_RPMH_ARC(sdm845, bi_tcxo, bi_tcxo_ao, "xo.lvl", 0x3, 2);
DEFINE_CLK_RPMH_VRM(sdm845, ln_bb_clk2, ln_bb_clk2_ao, "lnbclka2", 2);
@@ -217,6 +345,7 @@ static unsigned long clk_rpmh_recalc_rate(struct clk_hw *hw,
DEFINE_CLK_RPMH_VRM(sdm845, rf_clk1, rf_clk1_ao, "rfclka1", 1);
DEFINE_CLK_RPMH_VRM(sdm845, rf_clk2, rf_clk2_ao, "rfclka2", 1);
DEFINE_CLK_RPMH_VRM(sdm845, rf_clk3, rf_clk3_ao, "rfclka3", 1);
+DEFINE_CLK_RPMH_BCM(sdm845, ipa, "IP0");

static struct clk_hw *sdm845_rpmh_clocks[] = {
[RPMH_CXO_CLK] = &sdm845_bi_tcxo.hw,
@@ -231,6 +360,7 @@ static unsigned long clk_rpmh_recalc_rate(struct clk_hw *hw,
[RPMH_RF_CLK2_A] = &sdm845_rf_clk2_ao.hw,
[RPMH_RF_CLK3] = &sdm845_rf_clk3.hw,
[RPMH_RF_CLK3_A] = &sdm845_rf_clk3_ao.hw,
+ [RPMH_IPA_CLK] = &sdm845_ipa.hw,
};

static const struct clk_rpmh_desc clk_rpmh_sdm845 = {
@@ -267,6 +397,8 @@ static int clk_rpmh_probe(struct platform_device *pdev)

for (i = 0; i < desc->num_clks; i++) {
u32 res_addr;
+ size_t aux_data_len;
+ const struct bcm_db *data;

rpmh_clk = to_clk_rpmh(hw_clks[i]);
res_addr = cmd_db_read_addr(rpmh_clk->res_name);
@@ -275,6 +407,20 @@ static int clk_rpmh_probe(struct platform_device *pdev)
rpmh_clk->res_name);
return -ENODEV;
}
+
+ data = cmd_db_read_aux_data(rpmh_clk->res_name, &aux_data_len);
+ if (IS_ERR(data)) {
+ ret = PTR_ERR(data);
+ dev_err(&pdev->dev,
+ "error reading RPMh aux data for %s (%d)\n",
+ rpmh_clk->res_name, ret);
+ return ret;
+ }
+
+ /* Convert unit from Khz to Hz */
+ if (aux_data_len == sizeof(*data))
+ rpmh_clk->unit = le32_to_cpu(data->unit) * 1000ULL;
+
rpmh_clk->res_addr += res_addr;
rpmh_clk->dev = &pdev->dev;

diff --git a/include/dt-bindings/clock/qcom,rpmh.h b/include/dt-bindings/clock/qcom,rpmh.h
index f48fbd6..edcab3f 100644
--- a/include/dt-bindings/clock/qcom,rpmh.h
+++ b/include/dt-bindings/clock/qcom,rpmh.h
@@ -18,5 +18,6 @@
#define RPMH_RF_CLK2_A 9
#define RPMH_RF_CLK3 10
#define RPMH_RF_CLK3_A 11
+#define RPMH_IPA_CLK 12

#endif
--
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