diff mbox series

[v2,2/4] k210: clk: Refactor out_of_spec tests

Message ID 20210911172003.899301-2-seanga2@gmail.com
State Accepted
Delegated to: Andes
Headers show
Series [v2,1/4] clk: k210: Fix checking if ulongs are less than 0 | expand

Commit Message

Sean Anderson Sept. 11, 2021, 5:20 p.m. UTC 
Everything here sits in a while (true) loop. However, this introduces a
couple of layers of indentation. We can simplify the code by introducing a
single goto instead of using continue/break. This will also make adding
loops in the next patch easier.

Signed-off-by: Sean Anderson <seanga2@gmail.com>
---

(no changes since v1)

 drivers/clk/clk_kendryte.c | 105 ++++++++++++++++++-------------------
 1 file changed, 52 insertions(+), 53 deletions(-)

Comments

Leo Liang Sept. 14, 2021, 8:45 a.m. UTC | #1 
On Sat, Sep 11, 2021 at 01:20:01PM -0400, Sean Anderson wrote:
> Everything here sits in a while (true) loop. However, this introduces a
> couple of layers of indentation. We can simplify the code by introducing a
> single goto instead of using continue/break. This will also make adding
> loops in the next patch easier.
>
> Signed-off-by: Sean Anderson <seanga2@gmail.com>
> ---
>
> (no changes since v1)
>
>  drivers/clk/clk_kendryte.c | 105 ++++++++++++++++++-------------------
>  1 file changed, 52 insertions(+), 53 deletions(-)
>

Reviewed-by: Leo Yu-Chi Liang <ycliang@andestech.com>
CONFIDENTIALITY NOTICE:

This e-mail (and its attachments) may contain confidential and legally privileged information or information protected from disclosure. If you are not the intended recipient, you are hereby notified that any disclosure, copying, distribution, or use of the information contained herein is strictly prohibited. In this case, please immediately notify the sender by return e-mail, delete the message (and any accompanying documents) and destroy all printed hard copies. Thank you for your cooperation.

Copyright ANDES TECHNOLOGY CORPORATION - All Rights Reserved.
diff mbox series

Patch

diff --git a/drivers/clk/clk_kendryte.c b/drivers/clk/clk_kendryte.c
index 2caa21aec9..69691c4a04 100644
--- a/drivers/clk/clk_kendryte.c
+++ b/drivers/clk/clk_kendryte.c
@@ -709,6 +709,10 @@  TEST_STATIC int k210_pll_calc_config(u32 rate, u32 rate_in,
 		 * Whether we swapped r and od while enforcing frequency limits
 		 */
 		bool swapped = false;
+		/*
+		 * Whether the intermediate frequencies are out-of-spec
+		 */
+		bool out_of_spec;
 		u64 last_od = od;
 		u64 last_r = r;
 
@@ -767,76 +771,71 @@  TEST_STATIC int k210_pll_calc_config(u32 rate, u32 rate_in,
 		 * aren't in spec, try swapping r and od. If everything is
 		 * in-spec, calculate the relative error.
 		 */
-		while (true) {
+again:
+		out_of_spec = false;
+		if (r > max_r) {
+			out_of_spec = true;
+		} else {
 			/*
-			 * Whether the intermediate frequencies are out-of-spec
+			 * There is no way to only divide once; we need
+			 * to examine the frequency with and without the
+			 * effect of od.
 			 */
-			bool out_of_spec = false;
+			u64 vco = DIV_ROUND_CLOSEST_ULL(rate_in * f, r);
 
-			if (r > max_r) {
+			if (vco > 1750000000 || vco < 340000000)
 				out_of_spec = true;
-			} else {
-				/*
-				 * There is no way to only divide once; we need
-				 * to examine the frequency with and without the
-				 * effect of od.
-				 */
-				u64 vco = DIV_ROUND_CLOSEST_ULL(rate_in * f, r);
+		}
 
-				if (vco > 1750000000 || vco < 340000000)
-					out_of_spec = true;
+		if (out_of_spec) {
+			u64 new_r, new_od;
+
+			if (!swapped) {
+				u64 tmp = r;
+
+				r = od;
+				od = tmp;
+				swapped = true;
+				goto again;
 			}
 
-			if (out_of_spec) {
-				if (!swapped) {
-					u64 tmp = r;
-
-					r = od;
-					od = tmp;
-					swapped = true;
-					continue;
-				} else {
-					/*
-					 * Try looking ahead to see if there are
-					 * additional factors for the same
-					 * product.
-					 */
-					if (i + 1 < ARRAY_SIZE(factors)) {
-						u64 new_r, new_od;
-
-						i++;
-						new_r = UNPACK_R(factors[i]);
-						new_od = UNPACK_OD(factors[i]);
-						if (r * od == new_r * new_od) {
-							r = new_r;
-							od = new_od;
-							swapped = false;
-							continue;
-						}
-						i--;
-					}
-					break;
+			/*
+			 * Try looking ahead to see if there are additional
+			 * factors for the same product.
+			 */
+			if (i + 1 < ARRAY_SIZE(factors)) {
+				i++;
+				new_r = UNPACK_R(factors[i]);
+				new_od = UNPACK_OD(factors[i]);
+				if (r * od == new_r * new_od) {
+					r = new_r;
+					od = new_od;
+					swapped = false;
+					goto again;
 				}
+				i--;
 			}
 
-			error = DIV_ROUND_CLOSEST_ULL(f * inv_ratio, r * od);
-			/* The lower 16 bits are spurious */
-			error = abs((error - BIT(32))) >> 16;
+			/* We ran out of things to try */
+			continue;
+		}
 
-			if (error < best_error) {
-				best->r = r;
-				best->f = f;
-				best->od = od;
-				best_error = error;
-			}
-			break;
+		error = DIV_ROUND_CLOSEST_ULL(f * inv_ratio, r * od);
+		/* The lower 16 bits are spurious */
+		error = abs((error - BIT(32))) >> 16;
+
+		if (error < best_error) {
+			best->r = r;
+			best->f = f;
+			best->od = od;
+			best_error = error;
 		}
 	} while (f < 64 && i + 1 < ARRAY_SIZE(factors) && error != 0);
 
+	log_debug("best error %lld\n", best_error);
 	if (best_error == S64_MAX)
 		return -EINVAL;
 
-	log_debug("best error %lld\n", best_error);
 	return 0;
 }