mac80211: rt2x00: experimental improvements for MT7620 wifi

Serge Vasilugin reports:

To improve mt7620 built-in wifi performance some changes:
1. Correct BW20/BW40 switching (see comments with mark (1))
2. Correct TX_SW_CFG1 MAC reg from v3 of vendor driver see
	https://gitlab.com/dm38/padavan-ng/-/blob/master/trunk/proprietary/rt_wifi/rtpci/3.0.X.X/mt76x2/chips/rt6352.c#L531
3. Set bbp66 for all chains.
4. US_CYC_CNT init based on Programming guide, default value was 33 (pci),
   set chipset bus clock with fallback to cpu clock/3.
5. Don't overwrite default values for mt7620.
6. Correct some typos.
7. Add support for external LNA:
    a) RF and BBP regs never be corrected for this mode
    b) eLNA is driven the same way as ePA with mt7620's pin PA
	but vendor driver explicitly pin PA to gpio mode (for forrect calibration?)
	so I'm not sure that request for pa_pin in dts-file will be enough

First 5 changes (really 2) improve performance for boards w/o eLNA/ePA.
Changes 7 add support for eLNA

Configuration w/o eLAN/ePA and with eLNA show results
tx/rx (from router point of view) for each stream:
 35-40/30-35 Mbps for HT20
 65-70/60-65 Mbps for HT40

Yes. Max results for 2T2R client is 140-145/135-140
with peaks 160/150, It correspond to mediatek driver results.
Boards with ePA untested.

Reported-by: Serge Vasilugin <vasilugin@yandex.ru>
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
[directly include v3 of the patchset submitted upstream]
(cherry picked from commit 31a6605de04218e1c04bd5c2436c24d7d1c07506)
(cherry picked from commit e785ca05e9f0502894772f5df92192b816ba5d7c)
(cherry picked from commit 412fcf3d4400f84551f3ead0514834c62d94a251)

1 files changed, 139 insertions, 0 deletions

diff --git a/package/kernel/mac80211/patches/rt2x00/995-rt2x00-mt7620-introduce-accessors-for-CHIP_VER-register.patch b/package/kernel/mac80211/patches/rt2x00/995-rt2x00-mt7620-introduce-accessors-for-CHIP_VER-register.patch
new file mode 100644
index 0000000000..76114fe9ae
--- /dev/null
+++ b/package/kernel/mac80211/patches/rt2x00/995-rt2x00-mt7620-introduce-accessors-for-CHIP_VER-register.patch
@@ -0,0 +1,139 @@
+--- a/drivers/net/wireless/ralink/rt2x00/rt2800lib.h
++++ b/drivers/net/wireless/ralink/rt2x00/rt2800lib.h
+@@ -78,6 +78,9 @@ struct rt2800_ops {
+ 	int (*drv_init_registers)(struct rt2x00_dev *rt2x00dev);
+ 	__le32 *(*drv_get_txwi)(struct queue_entry *entry);
+ 	unsigned int (*drv_get_dma_done)(struct data_queue *queue);
++	int (*hw_get_chippkg)(void);
++	int (*hw_get_chipver)(void);
++	int (*hw_get_chipeco)(void);
+ };
+ 
+ static inline u32 rt2800_register_read(struct rt2x00_dev *rt2x00dev,
+@@ -195,6 +198,27 @@ static inline unsigned int rt2800_drv_ge
+ 	return rt2800ops->drv_get_dma_done(queue);
+ }
+ 
++static inline int rt2800_hw_get_chippkg(struct rt2x00_dev *rt2x00dev)
++{
++	const struct rt2800_ops *rt2800ops = rt2x00dev->ops->drv;
++
++	return rt2800ops->hw_get_chippkg();
++}
++
++static inline int rt2800_hw_get_chipver(struct rt2x00_dev *rt2x00dev)
++{
++	const struct rt2800_ops *rt2800ops = rt2x00dev->ops->drv;
++
++	return rt2800ops->hw_get_chipver();
++}
++
++static inline int rt2800_hw_get_chipeco(struct rt2x00_dev *rt2x00dev)
++{
++	const struct rt2800_ops *rt2800ops = rt2x00dev->ops->drv;
++
++	return rt2800ops->hw_get_chipeco();
++}
++
+ void rt2800_mcu_request(struct rt2x00_dev *rt2x00dev,
+ 			const u8 command, const u8 token,
+ 			const u8 arg0, const u8 arg1);
+--- a/drivers/net/wireless/ralink/rt2x00/rt2800pci.c
++++ b/drivers/net/wireless/ralink/rt2x00/rt2800pci.c
+@@ -286,6 +286,10 @@ static int rt2800pci_read_eeprom(struct
+ 	return retval;
+ }
+ 
++static int rt2800pci_get_chippkg(void) { return 0; }
++static int rt2800pci_get_chipver(void) { return 0; }
++static int rt2800pci_get_chipeco(void) { return 0; }
++
+ static const struct ieee80211_ops rt2800pci_mac80211_ops = {
+ 	.tx			= rt2x00mac_tx,
+ 	.start			= rt2x00mac_start,
+@@ -328,6 +332,9 @@ static const struct rt2800_ops rt2800pci
+ 	.drv_init_registers	= rt2800mmio_init_registers,
+ 	.drv_get_txwi		= rt2800mmio_get_txwi,
+ 	.drv_get_dma_done	= rt2800mmio_get_dma_done,
++	.hw_get_chippkg		= rt2800pci_get_chippkg,
++	.hw_get_chipver		= rt2800pci_get_chipver,
++	.hw_get_chipeco		= rt2800pci_get_chipeco,
+ };
+ 
+ static const struct rt2x00lib_ops rt2800pci_rt2x00_ops = {
+--- a/drivers/net/wireless/ralink/rt2x00/rt2800soc.c
++++ b/drivers/net/wireless/ralink/rt2x00/rt2800soc.c
+@@ -27,6 +27,12 @@
+ #include "rt2800lib.h"
+ #include "rt2800mmio.h"
+ 
++/* Needed to probe CHIP_VER register on MT7620 */
++#ifdef CONFIG_SOC_MT7620
++#include <asm/mach-ralink/ralink_regs.h>
++#include <asm/mach-ralink/mt7620.h>
++#endif
++
+ /* Allow hardware encryption to be disabled. */
+ static bool modparam_nohwcrypt;
+ module_param_named(nohwcrypt, modparam_nohwcrypt, bool, 0444);
+@@ -118,6 +124,27 @@ static int rt2800soc_write_firmware(stru
+ 	return 0;
+ }
+ 
++#ifdef CONFIG_SOC_MT7620
++static int rt2800soc_get_chippkg(void)
++{
++	return mt7620_get_pkg();
++}
++
++static int rt2800soc_get_chipver(void)
++{
++	return mt7620_get_chipver();
++}
++
++static int rt2800soc_get_chipeco(void)
++{
++	return mt7620_get_eco();
++}
++#else
++static int rt2800soc_get_chippkg(void) { return 0; }
++static int rt2800soc_get_chipver(void) { return 0; }
++static int rt2800soc_get_chipeco(void) { return 0; }
++#endif
++
+ static const struct ieee80211_ops rt2800soc_mac80211_ops = {
+ 	.tx			= rt2x00mac_tx,
+ 	.start			= rt2x00mac_start,
+@@ -159,6 +186,9 @@ static const struct rt2800_ops rt2800soc
+ 	.drv_init_registers	= rt2800mmio_init_registers,
+ 	.drv_get_txwi		= rt2800mmio_get_txwi,
+ 	.drv_get_dma_done	= rt2800mmio_get_dma_done,
++	.hw_get_chippkg		= rt2800soc_get_chippkg,
++	.hw_get_chipver		= rt2800soc_get_chipver,
++	.hw_get_chipeco		= rt2800soc_get_chipeco,
+ };
+ 
+ static const struct rt2x00lib_ops rt2800soc_rt2x00_ops = {
+--- a/drivers/net/wireless/ralink/rt2x00/rt2800usb.c
++++ b/drivers/net/wireless/ralink/rt2x00/rt2800usb.c
+@@ -628,6 +628,10 @@ static int rt2800usb_probe_hw(struct rt2
+ 	return 0;
+ }
+ 
++static int rt2800usb_get_chippkg(void) { return 0; }
++static int rt2800usb_get_chipver(void) { return 0; }
++static int rt2800usb_get_chipeco(void) { return 0; }
++
+ static const struct ieee80211_ops rt2800usb_mac80211_ops = {
+ 	.tx			= rt2x00mac_tx,
+ 	.start			= rt2x00mac_start,
+@@ -671,6 +675,9 @@ static const struct rt2800_ops rt2800usb
+ 	.drv_init_registers	= rt2800usb_init_registers,
+ 	.drv_get_txwi		= rt2800usb_get_txwi,
+ 	.drv_get_dma_done	= rt2800usb_get_dma_done,
++	.hw_get_chippkg		= rt2800usb_get_chippkg,
++	.hw_get_chipver		= rt2800usb_get_chipver,
++	.hw_get_chipeco		= rt2800usb_get_chipeco,
+ };
+ 
+ static const struct rt2x00lib_ops rt2800usb_rt2x00_ops = {