[PATCH v2 0/3] wireless: Use common cordic algorithm for b43 driver

[PATCH v2 0/3] wireless: Use common cordic algorithm for b43 driver

[Priit Laes]

b43 wireless driver includes an internal implementation of
cordic algorithm, although there's a common cordic library
which was split out from brcmsmac driver. Use that and drop
internal implementation.

During the process, brcmfmac was driver was also cleaned up.

Please note that this series is only compile-tested, as I
do not have access to the hardware.

Changes:
- Merged brcmsmac driver patches into single patch
- Merged b43 driver patches into single patch

Priit Laes (3):
  lib: cordic: Move cordic macros and defines to header file
  brcmsmac: Use cordic-related macros from common cordic library
  b43: Use cordic algorithm from kernel library

 drivers/net/wireless/broadcom/b43/Kconfig                      |  1 +-
 drivers/net/wireless/broadcom/b43/phy_common.c                 | 47 +-------
 drivers/net/wireless/broadcom/b43/phy_common.h                 |  9 +-
 drivers/net/wireless/broadcom/b43/phy_lp.c                     | 13 +-
 drivers/net/wireless/broadcom/b43/phy_n.c                      | 13 +-
 drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_int.h |  7 +-
 drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_lcn.c |  4 +-
 drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_n.c   |  4 +-
 include/linux/cordic.h                                         |  9 +-
 lib/cordic.c                                                   | 23 +---
 10 files changed, 35 insertions(+), 95 deletions(-)

base-commit: 651022382c7f8da46cb4872a545ee1da6d097d2a
-- 
git-series 0.9.1

[PATCH v2 1/3] lib: cordic: Move cordic macros and defines to header file

[Priit Laes]

Also append CORDIC_ prefix to nonprefixed macros.

Signed-off-by: Priit Laes <plaes@plaes.org>
---
 include/linux/cordic.h |  9 +++++++++
 lib/cordic.c           | 23 +++++++----------------
 2 files changed, 16 insertions(+), 16 deletions(-)

diff --git a/include/linux/cordic.h b/include/linux/cordic.h
index cf68ca4..3d656f5 100644
--- a/include/linux/cordic.h
+++ b/include/linux/cordic.h
@@ -18,6 +18,15 @@
 
 #include <linux/types.h>
 
+#define CORDIC_ANGLE_GEN	39797
+#define CORDIC_PRECISION_SHIFT	16
+#define CORDIC_NUM_ITER	(CORDIC_PRECISION_SHIFT + 2)
+
+#define CORDIC_FIXED(X)	((s32)((X) << CORDIC_PRECISION_SHIFT))
+#define CORDIC_FLOAT(X)	(((X) >= 0) \
+		? ((((X) >> (CORDIC_PRECISION_SHIFT - 1)) + 1) >> 1) \
+		: -((((-(X)) >> (CORDIC_PRECISION_SHIFT - 1)) + 1) >> 1))
+
 /**
  * struct cordic_iq - i/q coordinate.
  *
diff --git a/lib/cordic.c b/lib/cordic.c
index 6cf4778..8ef27c1 100644
--- a/lib/cordic.c
+++ b/lib/cordic.c
@@ -16,15 +16,6 @@
 #include <linux/module.h>
 #include <linux/cordic.h>
 
-#define CORDIC_ANGLE_GEN	39797
-#define CORDIC_PRECISION_SHIFT	16
-#define	CORDIC_NUM_ITER		(CORDIC_PRECISION_SHIFT + 2)
-
-#define	FIXED(X)	((s32)((X) << CORDIC_PRECISION_SHIFT))
-#define	FLOAT(X)	(((X) >= 0) \
-		? ((((X) >> (CORDIC_PRECISION_SHIFT - 1)) + 1) >> 1) \
-		: -((((-(X)) >> (CORDIC_PRECISION_SHIFT - 1)) + 1) >> 1))
-
 static const s32 arctan_table[] = {
 	2949120,
 	1740967,
@@ -64,16 +55,16 @@ struct cordic_iq cordic_calc_iq(s32 theta)
 	coord.q = 0;
 	angle = 0;
 
-	theta = FIXED(theta);
+	theta = CORDIC_FIXED(theta);
 	signtheta = (theta < 0) ? -1 : 1;
-	theta = ((theta + FIXED(180) * signtheta) % FIXED(360)) -
-		FIXED(180) * signtheta;
+	theta = ((theta + CORDIC_FIXED(180) * signtheta) % CORDIC_FIXED(360)) -
+		CORDIC_FIXED(180) * signtheta;
 
-	if (FLOAT(theta) > 90) {
-		theta -= FIXED(180);
+	if (CORDIC_FLOAT(theta) > 90) {
+		theta -= CORDIC_FIXED(180);
 		signx = -1;
-	} else if (FLOAT(theta) < -90) {
-		theta += FIXED(180);
+	} else if (CORDIC_FLOAT(theta) < -90) {
+		theta += CORDIC_FIXED(180);
 		signx = -1;
 	}
 
-- 
git-series 0.9.1

[PATCH v2 2/3] brcmsmac: Use cordic-related macros from common cordic library

[Priit Laes]

Current driver includes macro that is available from general cordic
library. Use that and drop unused duplicate and unneeded internal
definitions.

Signed-off-by: Priit Laes <plaes@plaes.org>

---
v2: Use single patch instead of change/removal patches.
---
 drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_int.h | 7 +-------
 drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_lcn.c | 4 ++--
 drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_n.c   | 4 ++--
 3 files changed, 4 insertions(+), 11 deletions(-)

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_int.h b/drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_int.h
index 4960f7d..e9e8337 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_int.h
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_int.h
@@ -220,13 +220,6 @@ enum phy_cal_mode {
 #define BB_MULT_MASK		0x0000ffff
 #define BB_MULT_VALID_MASK	0x80000000
 
-#define CORDIC_AG	39797
-#define	CORDIC_NI	18
-#define	FIXED(X)	((s32)((X) << 16))
-
-#define	FLOAT(X) \
-	(((X) >= 0) ? ((((X) >> 15) + 1) >> 1) : -((((-(X)) >> 15) + 1) >> 1))
-
 #define PHY_CHAIN_TX_DISABLE_TEMP	115
 #define PHY_HYSTERESIS_DELTATEMP	5
 
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_lcn.c b/drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_lcn.c
index 9fb0d9f..e78a93a 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_lcn.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_lcn.c
@@ -3447,8 +3447,8 @@ wlc_lcnphy_start_tx_tone(struct brcms_phy *pi, s32 f_kHz, u16 max_val,
 
 		theta += rot;
 
-		i_samp = (u16) (FLOAT(tone_samp.i * max_val) & 0x3ff);
-		q_samp = (u16) (FLOAT(tone_samp.q * max_val) & 0x3ff);
+		i_samp = (u16)(CORDIC_FLOAT(tone_samp.i * max_val) & 0x3ff);
+		q_samp = (u16)(CORDIC_FLOAT(tone_samp.q * max_val) & 0x3ff);
 		data_buf[t] = (i_samp << 10) | q_samp;
 	}
 
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_n.c b/drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_n.c
index a57f271..f4f5e90 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_n.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_n.c
@@ -23089,8 +23089,8 @@ wlc_phy_gen_load_samples_nphy(struct brcms_phy *pi, u32 f_kHz, u16 max_val,
 
 		theta += rot;
 
-		tone_buf[t].q = (s32) FLOAT(tone_buf[t].q * max_val);
-		tone_buf[t].i = (s32) FLOAT(tone_buf[t].i * max_val);
+		tone_buf[t].q = (s32)CORDIC_FLOAT(tone_buf[t].q * max_val);
+		tone_buf[t].i = (s32)CORDIC_FLOAT(tone_buf[t].i * max_val);
 	}
 
 	wlc_phy_loadsampletable_nphy(pi, tone_buf, num_samps);
-- 
git-series 0.9.1

[PATCH v2 3/3] b43: Use cordic algorithm from kernel library

[Priit Laes]

Kernel library has a common cordic algorithm which is identical
to internally implementatd one, so use it and drop the duplicate
implementation.

Signed-off-by: Priit Laes <plaes@plaes.org>

---
v2: Merge the update/removal patches into single patch.
---
 drivers/net/wireless/broadcom/b43/Kconfig      |  1 +-
 drivers/net/wireless/broadcom/b43/phy_common.c | 47 +-------------------
 drivers/net/wireless/broadcom/b43/phy_common.h |  9 +----
 drivers/net/wireless/broadcom/b43/phy_lp.c     | 13 ++---
 drivers/net/wireless/broadcom/b43/phy_n.c      | 13 ++---
 5 files changed, 15 insertions(+), 68 deletions(-)

diff --git a/drivers/net/wireless/broadcom/b43/Kconfig b/drivers/net/wireless/broadcom/b43/Kconfig
index fba8560..3e41457 100644
--- a/drivers/net/wireless/broadcom/b43/Kconfig
+++ b/drivers/net/wireless/broadcom/b43/Kconfig
@@ -4,6 +4,7 @@ config B43
 	select BCMA if B43_BCMA
 	select SSB if B43_SSB
 	select FW_LOADER
+	select CORDIC
 	---help---
 	  b43 is a driver for the Broadcom 43xx series wireless devices.
 
diff --git a/drivers/net/wireless/broadcom/b43/phy_common.c b/drivers/net/wireless/broadcom/b43/phy_common.c
index 85f2ca9..98c4fa5 100644
--- a/drivers/net/wireless/broadcom/b43/phy_common.c
+++ b/drivers/net/wireless/broadcom/b43/phy_common.c
@@ -604,50 +604,3 @@ void b43_phy_force_clock(struct b43_wldev *dev, bool force)
 #endif
 	}
 }
-
-/* http://bcm-v4.sipsolutions.net/802.11/PHY/Cordic */
-struct b43_c32 b43_cordic(int theta)
-{
-	static const u32 arctg[] = {
-		2949120, 1740967, 919879, 466945, 234379, 117304,
-		  58666,   29335,  14668,   7334,   3667,   1833,
-		    917,     458,    229,    115,     57,     29,
-	};
-	u8 i;
-	s32 tmp;
-	s8 signx = 1;
-	u32 angle = 0;
-	struct b43_c32 ret = { .i = 39797, .q = 0, };
-
-	while (theta > (180 << 16))
-		theta -= (360 << 16);
-	while (theta < -(180 << 16))
-		theta += (360 << 16);
-
-	if (theta > (90 << 16)) {
-		theta -= (180 << 16);
-		signx = -1;
-	} else if (theta < -(90 << 16)) {
-		theta += (180 << 16);
-		signx = -1;
-	}
-
-	for (i = 0; i <= 17; i++) {
-		if (theta > angle) {
-			tmp = ret.i - (ret.q >> i);
-			ret.q += ret.i >> i;
-			ret.i = tmp;
-			angle += arctg[i];
-		} else {
-			tmp = ret.i + (ret.q >> i);
-			ret.q -= ret.i >> i;
-			ret.i = tmp;
-			angle -= arctg[i];
-		}
-	}
-
-	ret.i *= signx;
-	ret.q *= signx;
-
-	return ret;
-}
diff --git a/drivers/net/wireless/broadcom/b43/phy_common.h b/drivers/net/wireless/broadcom/b43/phy_common.h
index 57a1ad8..4213cac 100644
--- a/drivers/net/wireless/broadcom/b43/phy_common.h
+++ b/drivers/net/wireless/broadcom/b43/phy_common.h
@@ -7,13 +7,6 @@
 
 struct b43_wldev;
 
-/* Complex number using 2 32-bit signed integers */
-struct b43_c32 { s32 i, q; };
-
-#define CORDIC_CONVERT(value)	(((value) >= 0) ? \
-				 ((((value) >> 15) + 1) >> 1) : \
-				 -((((-(value)) >> 15) + 1) >> 1))
-
 /* PHY register routing bits */
 #define B43_PHYROUTE			0x0C00 /* PHY register routing bits mask */
 #define  B43_PHYROUTE_BASE		0x0000 /* Base registers */
@@ -450,6 +443,4 @@ bool b43_is_40mhz(struct b43_wldev *dev);
 
 void b43_phy_force_clock(struct b43_wldev *dev, bool force);
 
-struct b43_c32 b43_cordic(int theta);
-
 #endif /* LINUX_B43_PHY_COMMON_H_ */
diff --git a/drivers/net/wireless/broadcom/b43/phy_lp.c b/drivers/net/wireless/broadcom/b43/phy_lp.c
index 6922cbb..1718e3b 100644
--- a/drivers/net/wireless/broadcom/b43/phy_lp.c
+++ b/drivers/net/wireless/broadcom/b43/phy_lp.c
@@ -23,6 +23,7 @@
 
 */
 
+#include <linux/cordic.h>
 #include <linux/slab.h>
 
 #include "b43.h"
@@ -1780,9 +1781,9 @@ static void lpphy_start_tx_tone(struct b43_wldev *dev, s32 freq, u16 max)
 {
 	struct b43_phy_lp *lpphy = dev->phy.lp;
 	u16 buf[64];
-	int i, samples = 0, angle = 0;
+	int i, samples = 0, theta = 0;
 	int rotation = (((36 * freq) / 20) << 16) / 100;
-	struct b43_c32 sample;
+	struct cordic_iq sample;
 
 	lpphy->tx_tone_freq = freq;
 
@@ -1798,10 +1799,10 @@ static void lpphy_start_tx_tone(struct b43_wldev *dev, s32 freq, u16 max)
 	}
 
 	for (i = 0; i < samples; i++) {
-		sample = b43_cordic(angle);
-		angle += rotation;
-		buf[i] = CORDIC_CONVERT((sample.i * max) & 0xFF) << 8;
-		buf[i] |= CORDIC_CONVERT((sample.q * max) & 0xFF);
+		sample = cordic_calc_iq(theta);
+		theta += rotation;
+		buf[i] = CORDIC_FLOAT((sample.i * max) & 0xFF) << 8;
+		buf[i] |= CORDIC_FLOAT((sample.q * max) & 0xFF);
 	}
 
 	b43_lptab_write_bulk(dev, B43_LPTAB16(5, 0), samples, buf);
diff --git a/drivers/net/wireless/broadcom/b43/phy_n.c b/drivers/net/wireless/broadcom/b43/phy_n.c
index 44ab080..1f9378a 100644
--- a/drivers/net/wireless/broadcom/b43/phy_n.c
+++ b/drivers/net/wireless/broadcom/b43/phy_n.c
@@ -23,6 +23,7 @@
 
 */
 
+#include <linux/cordic.h>
 #include <linux/delay.h>
 #include <linux/slab.h>
 #include <linux/types.h>
@@ -1513,7 +1514,7 @@ static void b43_radio_init2055(struct b43_wldev *dev)
 
 /* http://bcm-v4.sipsolutions.net/802.11/PHY/N/LoadSampleTable */
 static int b43_nphy_load_samples(struct b43_wldev *dev,
-					struct b43_c32 *samples, u16 len) {
+					struct cordic_iq *samples, u16 len) {
 	struct b43_phy_n *nphy = dev->phy.n;
 	u16 i;
 	u32 *data;
@@ -1544,7 +1545,7 @@ static u16 b43_nphy_gen_load_samples(struct b43_wldev *dev, u32 freq, u16 max,
 {
 	int i;
 	u16 bw, len, rot, angle;
-	struct b43_c32 *samples;
+	struct cordic_iq *samples;
 
 	bw = b43_is_40mhz(dev) ? 40 : 20;
 	len = bw << 3;
@@ -1561,7 +1562,7 @@ static u16 b43_nphy_gen_load_samples(struct b43_wldev *dev, u32 freq, u16 max,
 		len = bw << 1;
 	}
 
-	samples = kcalloc(len, sizeof(struct b43_c32), GFP_KERNEL);
+	samples = kcalloc(len, sizeof(struct cordic_iq), GFP_KERNEL);
 	if (!samples) {
 		b43err(dev->wl, "allocation for samples generation failed\n");
 		return 0;
@@ -1570,10 +1571,10 @@ static u16 b43_nphy_gen_load_samples(struct b43_wldev *dev, u32 freq, u16 max,
 	angle = 0;
 
 	for (i = 0; i < len; i++) {
-		samples[i] = b43_cordic(angle);
+		samples[i] = cordic_calc_iq(angle);
 		angle += rot;
-		samples[i].q = CORDIC_CONVERT(samples[i].q * max);
-		samples[i].i = CORDIC_CONVERT(samples[i].i * max);
+		samples[i].q = CORDIC_FLOAT(samples[i].q * max);
+		samples[i].i = CORDIC_FLOAT(samples[i].i * max);
 	}
 
 	i = b43_nphy_load_samples(dev, samples, len);
-- 
git-series 0.9.1

Re: [PATCH v2 3/3] b43: Use cordic algorithm from kernel library

[Michael Büsch]

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On Mon,  5 Nov 2018 21:37:18 +0200
Priit Laes <plaes@plaes.org> wrote:

> Kernel library has a common cordic algorithm which is identical
> to internally implementatd one, so use it and drop the duplicate
> implementation.
> 
> Signed-off-by: Priit Laes <plaes@plaes.org>


This looks nice.
But what is the testing status of this?
Has this been tested on actual b43-LP hardware?

Is the replacement algorithm exactly the same, or are there slight
differences (e.g. in corner cases)?

-- 
Michael

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Re: [PATCH v2 1/3] lib: cordic: Move cordic macros and defines to header file

[Arend van Spriel]

On 11/5/2018 8:37 PM, Priit Laes wrote:
> Also append CORDIC_ prefix to nonprefixed macros.

Bit annoying that you made me look at LKML for this patch. Can you just 
post the entire series to linux-wireless so Kalle can take it all 
through his tree. Also the commit message is a bit thin. Please explain 
why these are moved to the header file.

Reviewed-by: Arend van Spriel <arend.vanspriel@broadcom.com>
> Signed-off-by: Priit Laes <plaes@plaes.org>
> ---
>  include/linux/cordic.h |  9 +++++++++
>  lib/cordic.c           | 23 +++++++----------------
>  2 files changed, 16 insertions(+), 16 deletions(-)

Re: [PATCH v2 3/3] b43: Use cordic algorithm from kernel library

[Arend van Spriel]

On 11/5/2018 10:39 PM, Michael Büsch wrote:
> On Mon,  5 Nov 2018 21:37:18 +0200
> Priit Laes <plaes@plaes.org> wrote:
>
>> Kernel library has a common cordic algorithm which is identical
>> to internally implementatd one, so use it and drop the duplicate
>> implementation.
>>
>> Signed-off-by: Priit Laes <plaes@plaes.org>
>
>
> This looks nice.
> But what is the testing status of this?
> Has this been tested on actual b43-LP hardware?
>
> Is the replacement algorithm exactly the same, or are there slight
> differences (e.g. in corner cases)?

Hi Michael,

I recall doing a comparison between the algorithms and thought I put 
that in the original commit message. However, it is not there. It is not 
exactly the same as in b43 so there are difference for certain angles, 
most results are the same however. This implementation is slightly more 
accurate on the full scale.

Re: [PATCH v2 1/3] lib: cordic: Move cordic macros and defines to header file

[Priit Laes]

On Mon, Nov 05, 2018 at 11:02:35PM +0100, Arend van Spriel wrote:
> On 11/5/2018 8:37 PM, Priit Laes wrote:
> > Also append CORDIC_ prefix to nonprefixed macros.
> 
> Bit annoying that you made me look at LKML for this patch. Can you just post
> the entire series to linux-wireless so Kalle can take it all through his
> tree. Also the commit message is a bit thin. Please explain why these are
> moved to the header file.

Sorry, I messed up again while trying to automate the send-email with
get_maintainers script (dry-run argument did not work .gitconfig :S)

> 
> Reviewed-by: Arend van Spriel <arend.vanspriel@broadcom.com>
> > Signed-off-by: Priit Laes <plaes@plaes.org>
> > ---
> >  include/linux/cordic.h |  9 +++++++++
> >  lib/cordic.c           | 23 +++++++----------------
> >  2 files changed, 16 insertions(+), 16 deletions(-)
> 

Re: [PATCH v2 1/3] lib: cordic: Move cordic macros and defines to header file

[Arend van Spriel]

On 11/6/2018 8:14 AM, Priit Laes wrote:
> On Mon, Nov 05, 2018 at 11:02:35PM +0100, Arend van Spriel wrote:
>> On 11/5/2018 8:37 PM, Priit Laes wrote:
>>> Also append CORDIC_ prefix to nonprefixed macros.
>>
>> Bit annoying that you made me look at LKML for this patch. Can you just post
>> the entire series to linux-wireless so Kalle can take it all through his
>> tree. Also the commit message is a bit thin. Please explain why these are
>> moved to the header file.
>
> Sorry, I messed up again while trying to automate the send-email with
> get_maintainers script (dry-run argument did not work .gitconfig :S)

No worries. It was only a bit annoying ;-)

Regards,
Arend