1 files changed, 112 insertions, 41 deletions

diff --git a/drivers/clk/bcm/clk-bcm2835.c b/drivers/clk/bcm/clk-bcm2835.c
index 6bb7efa12037..02215ea79403 100644
--- a/drivers/clk/bcm/clk-bcm2835.c
+++ b/drivers/clk/bcm/clk-bcm2835.c
@@ -30,8 +30,9 @@
 #include <linux/debugfs.h>
 #include <linux/delay.h>
 #include <linux/io.h>
+#include <linux/math.h>
 #include <linux/module.h>
-#include <linux/of_device.h>
+#include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <dt-bindings/clock/bcm2835.h>
@@ -314,6 +315,7 @@ struct bcm2835_cprman {
 	struct device *dev;
 	void __iomem *regs;
 	spinlock_t regs_lock; /* spinlock for all clocks */
+	unsigned int soc;
 
 	/*
 	 * Real names of cprman clock parents looked up through
@@ -421,6 +423,7 @@ struct bcm2835_pll_data {
 	u32 reference_enable_mask;
 	/* Bit in CM_LOCK to indicate when the PLL has locked. */
 	u32 lock_mask;
+	u32 flags;
 
 	const struct bcm2835_pll_ana_bits *ana;
 
@@ -500,6 +503,8 @@ struct bcm2835_clock_data {
 	bool low_jitter;
 
 	u32 tcnt_mux;
+
+	bool round_up;
 };
 
 struct bcm2835_gate_data {
@@ -525,6 +530,20 @@ static int bcm2835_pll_is_on(struct clk_hw *hw)
 		A2W_PLL_CTRL_PRST_DISABLE;
 }
 
+static u32 bcm2835_pll_get_prediv_mask(struct bcm2835_cprman *cprman,
+				       const struct bcm2835_pll_data *data)
+{
+	/*
+	 * On BCM2711 there isn't a pre-divisor available in the PLL feedback
+	 * loop. Bits 13:14 of ANA1 (PLLA,PLLB,PLLC,PLLD) have been re-purposed
+	 * for to for VCO RANGE bits.
+	 */
+	if (cprman->soc & SOC_BCM2711)
+		return 0;
+
+	return data->ana->fb_prediv_mask;
+}
+
 static void bcm2835_pll_choose_ndiv_and_fdiv(unsigned long rate,
 					     unsigned long parent_rate,
 					     u32 *ndiv, u32 *fdiv)
@@ -551,18 +570,23 @@ static long bcm2835_pll_rate_from_divisors(unsigned long parent_rate,
 	return rate >> A2W_PLL_FRAC_BITS;
 }
 
-static long bcm2835_pll_round_rate(struct clk_hw *hw, unsigned long rate,
-				   unsigned long *parent_rate)
+static int bcm2835_pll_determine_rate(struct clk_hw *hw,
+				      struct clk_rate_request *req)
 {
 	struct bcm2835_pll *pll = container_of(hw, struct bcm2835_pll, hw);
 	const struct bcm2835_pll_data *data = pll->data;
 	u32 ndiv, fdiv;
 
-	rate = clamp(rate, data->min_rate, data->max_rate);
+	req->rate = clamp(req->rate, data->min_rate, data->max_rate);
 
-	bcm2835_pll_choose_ndiv_and_fdiv(rate, *parent_rate, &ndiv, &fdiv);
+	bcm2835_pll_choose_ndiv_and_fdiv(req->rate, req->best_parent_rate,
+					 &ndiv, &fdiv);
 
-	return bcm2835_pll_rate_from_divisors(*parent_rate, ndiv, fdiv, 1);
+	req->rate = bcm2835_pll_rate_from_divisors(req->best_parent_rate,
+						   ndiv, fdiv,
+						   1);
+
+	return 0;
 }
 
 static unsigned long bcm2835_pll_get_rate(struct clk_hw *hw,
@@ -582,7 +606,7 @@ static unsigned long bcm2835_pll_get_rate(struct clk_hw *hw,
 	ndiv = (a2wctrl & A2W_PLL_CTRL_NDIV_MASK) >> A2W_PLL_CTRL_NDIV_SHIFT;
 	pdiv = (a2wctrl & A2W_PLL_CTRL_PDIV_MASK) >> A2W_PLL_CTRL_PDIV_SHIFT;
 	using_prediv = cprman_read(cprman, data->ana_reg_base + 4) &
-		data->ana->fb_prediv_mask;
+		       bcm2835_pll_get_prediv_mask(cprman, data);
 
 	if (using_prediv) {
 		ndiv *= 2;
@@ -665,6 +689,7 @@ static int bcm2835_pll_set_rate(struct clk_hw *hw,
 	struct bcm2835_pll *pll = container_of(hw, struct bcm2835_pll, hw);
 	struct bcm2835_cprman *cprman = pll->cprman;
 	const struct bcm2835_pll_data *data = pll->data;
+	u32 prediv_mask = bcm2835_pll_get_prediv_mask(cprman, data);
 	bool was_using_prediv, use_fb_prediv, do_ana_setup_first;
 	u32 ndiv, fdiv, a2w_ctl;
 	u32 ana[4];
@@ -682,7 +707,7 @@ static int bcm2835_pll_set_rate(struct clk_hw *hw,
 	for (i = 3; i >= 0; i--)
 		ana[i] = cprman_read(cprman, data->ana_reg_base + i * 4);
 
-	was_using_prediv = ana[1] & data->ana->fb_prediv_mask;
+	was_using_prediv = ana[1] & prediv_mask;
 
 	ana[0] &= ~data->ana->mask0;
 	ana[0] |= data->ana->set0;
@@ -692,10 +717,10 @@ static int bcm2835_pll_set_rate(struct clk_hw *hw,
 	ana[3] |= data->ana->set3;
 
 	if (was_using_prediv && !use_fb_prediv) {
-		ana[1] &= ~data->ana->fb_prediv_mask;
+		ana[1] &= ~prediv_mask;
 		do_ana_setup_first = true;
 	} else if (!was_using_prediv && use_fb_prediv) {
-		ana[1] |= data->ana->fb_prediv_mask;
+		ana[1] |= prediv_mask;
 		do_ana_setup_first = false;
 	} else {
 		do_ana_setup_first = true;
@@ -763,7 +788,7 @@ static const struct clk_ops bcm2835_pll_clk_ops = {
 	.unprepare = bcm2835_pll_off,
 	.recalc_rate = bcm2835_pll_get_rate,
 	.set_rate = bcm2835_pll_set_rate,
-	.round_rate = bcm2835_pll_round_rate,
+	.determine_rate = bcm2835_pll_determine_rate,
 	.debug_init = bcm2835_pll_debug_init,
 };
 
@@ -788,11 +813,10 @@ static int bcm2835_pll_divider_is_on(struct clk_hw *hw)
 	return !(cprman_read(cprman, data->a2w_reg) & A2W_PLL_CHANNEL_DISABLE);
 }
 
-static long bcm2835_pll_divider_round_rate(struct clk_hw *hw,
-					   unsigned long rate,
-					   unsigned long *parent_rate)
+static int bcm2835_pll_divider_determine_rate(struct clk_hw *hw,
+					      struct clk_rate_request *req)
 {
-	return clk_divider_ops.round_rate(hw, rate, parent_rate);
+	return clk_divider_ops.determine_rate(hw, req);
 }
 
 static unsigned long bcm2835_pll_divider_get_rate(struct clk_hw *hw,
@@ -884,7 +908,7 @@ static const struct clk_ops bcm2835_pll_divider_clk_ops = {
 	.unprepare = bcm2835_pll_divider_off,
 	.recalc_rate = bcm2835_pll_divider_get_rate,
 	.set_rate = bcm2835_pll_divider_set_rate,
-	.round_rate = bcm2835_pll_divider_round_rate,
+	.determine_rate = bcm2835_pll_divider_determine_rate,
 	.debug_init = bcm2835_pll_divider_debug_init,
 };
 
@@ -916,23 +940,17 @@ static int bcm2835_clock_is_on(struct clk_hw *hw)
 
 static u32 bcm2835_clock_choose_div(struct clk_hw *hw,
 				    unsigned long rate,
-				    unsigned long parent_rate,
-				    bool round_up)
+				    unsigned long parent_rate)
 {
 	struct bcm2835_clock *clock = bcm2835_clock_from_hw(hw);
 	const struct bcm2835_clock_data *data = clock->data;
 	u32 unused_frac_mask =
 		GENMASK(CM_DIV_FRAC_BITS - data->frac_bits, 0) >> 1;
 	u64 temp = (u64)parent_rate << CM_DIV_FRAC_BITS;
-	u64 rem;
 	u32 div, mindiv, maxdiv;
 
-	rem = do_div(temp, rate);
+	do_div(temp, rate);
 	div = temp;
-
-	/* Round up and mask off the unused bits */
-	if (round_up && ((div & unused_frac_mask) != 0 || rem != 0))
-		div += unused_frac_mask + 1;
 	div &= ~unused_frac_mask;
 
 	/* different clamping limits apply for a mash clock */
@@ -956,9 +974,9 @@ static u32 bcm2835_clock_choose_div(struct clk_hw *hw,
 	return div;
 }
 
-static long bcm2835_clock_rate_from_divisor(struct bcm2835_clock *clock,
-					    unsigned long parent_rate,
-					    u32 div)
+static unsigned long bcm2835_clock_rate_from_divisor(struct bcm2835_clock *clock,
+						     unsigned long parent_rate,
+						     u32 div)
 {
 	const struct bcm2835_clock_data *data = clock->data;
 	u64 temp;
@@ -983,12 +1001,34 @@ static long bcm2835_clock_rate_from_divisor(struct bcm2835_clock *clock,
 	return temp;
 }
 
+static unsigned long bcm2835_round_rate(unsigned long rate)
+{
+	unsigned long scaler;
+	unsigned long limit;
+
+	limit = rate / 100000;
+
+	scaler = 1;
+	while (scaler < limit)
+		scaler *= 10;
+
+	/*
+	 * If increasing a clock by less than 0.1% changes it
+	 * from ..999.. to ..000.., round up.
+	 */
+	if ((rate + scaler - 1) / scaler % 1000 == 0)
+		rate = roundup(rate, scaler);
+
+	return rate;
+}
+
 static unsigned long bcm2835_clock_get_rate(struct clk_hw *hw,
 					    unsigned long parent_rate)
 {
 	struct bcm2835_clock *clock = bcm2835_clock_from_hw(hw);
 	struct bcm2835_cprman *cprman = clock->cprman;
 	const struct bcm2835_clock_data *data = clock->data;
+	unsigned long rate;
 	u32 div;
 
 	if (data->int_bits == 0 && data->frac_bits == 0)
@@ -996,7 +1036,12 @@ static unsigned long bcm2835_clock_get_rate(struct clk_hw *hw,
 
 	div = cprman_read(cprman, data->div_reg);
 
-	return bcm2835_clock_rate_from_divisor(clock, parent_rate, div);
+	rate = bcm2835_clock_rate_from_divisor(clock, parent_rate, div);
+
+	if (data->round_up)
+		rate = bcm2835_round_rate(rate);
+
+	return rate;
 }
 
 static void bcm2835_clock_wait_busy(struct bcm2835_clock *clock)
@@ -1063,7 +1108,7 @@ static int bcm2835_clock_set_rate(struct clk_hw *hw,
 	struct bcm2835_clock *clock = bcm2835_clock_from_hw(hw);
 	struct bcm2835_cprman *cprman = clock->cprman;
 	const struct bcm2835_clock_data *data = clock->data;
-	u32 div = bcm2835_clock_choose_div(hw, rate, parent_rate, false);
+	u32 div = bcm2835_clock_choose_div(hw, rate, parent_rate);
 	u32 ctl;
 
 	spin_lock(&cprman->regs_lock);
@@ -1114,7 +1159,7 @@ static unsigned long bcm2835_clock_choose_div_and_prate(struct clk_hw *hw,
 
 	if (!(BIT(parent_idx) & data->set_rate_parent)) {
 		*prate = clk_hw_get_rate(parent);
-		*div = bcm2835_clock_choose_div(hw, rate, *prate, true);
+		*div = bcm2835_clock_choose_div(hw, rate, *prate);
 
 		*avgrate = bcm2835_clock_rate_from_divisor(clock, *prate, *div);
 
@@ -1200,7 +1245,7 @@ static int bcm2835_clock_determine_rate(struct clk_hw *hw,
 		rate = bcm2835_clock_choose_div_and_prate(hw, i, req->rate,
 							  &div, &prate,
 							  &avgrate);
-		if (rate > best_rate && rate <= req->rate) {
+		if (abs(req->rate - rate) < abs(req->rate - best_rate)) {
 			best_parent = parent;
 			best_prate = prate;
 			best_rate = rate;
@@ -1310,7 +1355,7 @@ static struct clk_hw *bcm2835_register_pll(struct bcm2835_cprman *cprman,
 	init.num_parents = 1;
 	init.name = pll_data->name;
 	init.ops = &bcm2835_pll_clk_ops;
-	init.flags = CLK_IGNORE_UNUSED;
+	init.flags = pll_data->flags | CLK_IGNORE_UNUSED;
 
 	pll = kzalloc(sizeof(*pll), GFP_KERNEL);
 	if (!pll)
@@ -1321,8 +1366,10 @@ static struct clk_hw *bcm2835_register_pll(struct bcm2835_cprman *cprman,
 	pll->hw.init = &init;
 
 	ret = devm_clk_hw_register(cprman->dev, &pll->hw);
-	if (ret)
+	if (ret) {
+		kfree(pll);
 		return NULL;
+	}
 	return &pll->hw;
 }
 
@@ -1508,7 +1555,7 @@ static const char *const bcm2835_clock_osc_parents[] = {
 	.parents = bcm2835_clock_osc_parents,				\
 	__VA_ARGS__)
 
-/* main peripherial parent mux */
+/* main peripheral parent mux */
 static const char *const bcm2835_clock_per_parents[] = {
 	"gnd",
 	"xosc",
@@ -1684,10 +1731,33 @@ static const struct bcm2835_clk_desc clk_desc_array[] = {
 		.fixed_divider = 1,
 		.flags = CLK_SET_RATE_PARENT),
 
-	/*
-	 * PLLB is used for the ARM's clock. Controlled by firmware, see
-	 * clk-raspberrypi.c.
-	 */
+	/* PLLB is used for the ARM's clock. */
+	[BCM2835_PLLB]		= REGISTER_PLL(
+		SOC_ALL,
+		.name = "pllb",
+		.cm_ctrl_reg = CM_PLLB,
+		.a2w_ctrl_reg = A2W_PLLB_CTRL,
+		.frac_reg = A2W_PLLB_FRAC,
+		.ana_reg_base = A2W_PLLB_ANA0,
+		.reference_enable_mask = A2W_XOSC_CTRL_PLLB_ENABLE,
+		.lock_mask = CM_LOCK_FLOCKB,
+
+		.ana = &bcm2835_ana_default,
+
+		.min_rate = 600000000u,
+		.max_rate = 3000000000u,
+		.max_fb_rate = BCM2835_MAX_FB_RATE,
+		.flags = CLK_GET_RATE_NOCACHE),
+	[BCM2835_PLLB_ARM]	= REGISTER_PLL_DIV(
+		SOC_ALL,
+		.name = "pllb_arm",
+		.source_pll = "pllb",
+		.cm_reg = CM_PLLB,
+		.a2w_reg = A2W_PLLB_ARM,
+		.load_mask = CM_PLLB_LOADARM,
+		.hold_mask = CM_PLLB_HOLDARM,
+		.fixed_divider = 1,
+		.flags = CLK_SET_RATE_PARENT | CLK_GET_RATE_NOCACHE),
 
 	/*
 	 * PLLC is the core PLL, used to drive the core VPU clock.
@@ -1749,7 +1819,7 @@ static const struct bcm2835_clk_desc clk_desc_array[] = {
 		.load_mask = CM_PLLC_LOADPER,
 		.hold_mask = CM_PLLC_HOLDPER,
 		.fixed_divider = 1,
-		.flags = CLK_SET_RATE_PARENT),
+		.flags = CLK_IS_CRITICAL | CLK_SET_RATE_PARENT),
 
 	/*
 	 * PLLD is the display PLL, used to drive DSI display panels.
@@ -2108,7 +2178,8 @@ static const struct bcm2835_clk_desc clk_desc_array[] = {
 		.div_reg = CM_UARTDIV,
 		.int_bits = 10,
 		.frac_bits = 12,
-		.tcnt_mux = 28),
+		.tcnt_mux = 28,
+		.round_up = true),
 
 	/* TV encoder clock.  Only operating frequency is 108Mhz.  */
 	[BCM2835_CLOCK_VEC]	= REGISTER_PER_CLK(
@@ -2238,6 +2309,7 @@ static int bcm2835_clk_probe(struct platform_device *pdev)
 	platform_set_drvdata(pdev, cprman);
 
 	cprman->onecell.num = asize;
+	cprman->soc = pdata->soc;
 	hws = cprman->onecell.hws;
 
 	for (i = 0; i < asize; i++) {
@@ -2283,4 +2355,3 @@ builtin_platform_driver(bcm2835_clk_driver);
 
 MODULE_AUTHOR("Eric Anholt <eric@anholt.net>");
 MODULE_DESCRIPTION("BCM2835 clock driver");
-MODULE_LICENSE("GPL");