iwlwifi: pcie: enable LP XTAL to reduce power consumption

1. Enable LP XTAL to avoid HW bug where device may consume much
power if FW is not loaded after device reset. LP XTAL is
disabled by default after device HW reset. Configure device's
"persistence" mode to avoid resetting XTAL again when SHRD_HW_RST
occurs in S3.

2. Add methods to access SHR (shared block memory space) directly from PCI
bus w/o need to power up MAC HW.

Shared internal registers (e.g. SHR_APMG_GP1, SHR_APMG_XTAL_CFG)can be
accessed directly from PCI bus through SHR arbiter even when MAC HW is
powered down. This is possible due to indirect read/write via
HEEP_CTRL_WRD_PCIEX_CTRL (0xEC) and HEEP_CTRL_WRD_PCIEX_DATA (0xF4)
registers.

Use iwl_write32()/iwl_read32() family to access these registers. The MAC HW
need not be powered up so no "grab inc access" is required.

For example, to read from SHR_APMG_GP1 register (0x1DC),
first, write to the control register:
HEEP_CTRL_WRD_PCIEX_CTRL[15:0] = 0x1DC (offset of the SHR_APMG_GP1 register)
HEEP_CTRL_WRD_PCIEX_CTRL[29:28] = 2 (read access)
second, read from the data register HEEP_CTRL_WRD_PCIEX_DATA[31:0].

To write the register, first, write to the data register
HEEP_CTRL_WRD_PCIEX_DATA[31:0] and then:
HEEP_CTRL_WRD_PCIEX_CTRL[15:0] = 0x1DC (offset of the SHR_APMG_GP1 register)
HEEP_CTRL_WRD_PCIEX_CTRL[29:28] = 3 (write access)

Signed-off-by: Alexander Bondar <alexander.bondar@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

1 files changed, 22 insertions, 1 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-prph.h b/drivers/net/wireless/iwlwifi/iwl-prph.h
index 9c90186..5f657c5 100644
--- a/drivers/net/wireless/iwlwifi/iwl-prph.h
+++ b/drivers/net/wireless/iwlwifi/iwl-prph.h
@@ -95,7 +95,8 @@
 #define APMG_SVR_VOLTAGE_CONFIG_BIT_MSK	(0x000001E0) /* bit 8:5 */
 #define APMG_SVR_DIGITAL_VOLTAGE_1_32		(0x00000060)
 
-#define APMG_PCIDEV_STT_VAL_L1_ACT_DIS		(0x00000800)
+#define APMG_PCIDEV_STT_VAL_PERSIST_DIS	(0x00000200)
+#define APMG_PCIDEV_STT_VAL_L1_ACT_DIS	(0x00000800)
 
 #define APMG_RTC_INT_STT_RFKILL		(0x10000000)
 
@@ -105,6 +106,26 @@
 /* Device NMI register */
 #define DEVICE_SET_NMI_REG 0x00a01c30
 
+/* Shared registers (0x0..0x3ff, via target indirect or periphery */
+#define SHR_BASE	0x00a10000
+
+/* Shared GP1 register */
+#define SHR_APMG_GP1_REG		0x01dc
+#define SHR_APMG_GP1_REG_PRPH		(SHR_BASE + SHR_APMG_GP1_REG)
+#define SHR_APMG_GP1_WF_XTAL_LP_EN	0x00000004
+#define SHR_APMG_GP1_CHICKEN_BIT_SELECT	0x80000000
+
+/* Shared DL_CFG register */
+#define SHR_APMG_DL_CFG_REG			0x01c4
+#define SHR_APMG_DL_CFG_REG_PRPH		(SHR_BASE + SHR_APMG_DL_CFG_REG)
+#define SHR_APMG_DL_CFG_RTCS_CLK_SELECTOR_MSK	0x000000c0
+#define SHR_APMG_DL_CFG_RTCS_CLK_INTERNAL_XTAL	0x00000080
+#define SHR_APMG_DL_CFG_DL_CLOCK_POWER_UP	0x00000100
+
+/* Shared APMG_XTAL_CFG register */
+#define SHR_APMG_XTAL_CFG_REG		0x1c0
+#define SHR_APMG_XTAL_CFG_XTAL_ON_REQ	0x80000000
+
 /*
  * Device reset for family 8000
  * write to bit 24 in order to reset the CPU