[PATCH] pch_phub: unify the inital UART clock rate for EG20T and ML7213

[Feng Tang]

Set the base clk rate to 192MHz, so that the pch_uart driver can
have the unique uartclk value, and don't need to add quirks for
different boards and configurations.

Signed-off-by: Feng Tang <feng.tang@xxxxxxxxx>
---
 drivers/misc/pch_phub.c |   16 ++++++++++++----
 1 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/drivers/misc/pch_phub.c b/drivers/misc/pch_phub.c
index 10fc478..bbe4db9 100644
--- a/drivers/misc/pch_phub.c
+++ b/drivers/misc/pch_phub.c
@@ -731,10 +731,8 @@ static int __devinit pch_phub_probe(struct pci_dev *pdev,
 					       CLKCFG_CAN_50MHZ,
 					       CLKCFG_CANCLK_MASK);
 
-		/* quirk for CM-iTC board */
-		board_name = dmi_get_system_info(DMI_BOARD_NAME);
-		if (board_name && strstr(board_name, "CM-iTC"))
-			pch_phub_read_modify_write_reg(chip,
+		/* Set the UART base clk rate to 192MHz */
+		pch_phub_read_modify_write_reg(chip,
 						(unsigned int)CLKCFG_REG_OFFSET,
 						CLKCFG_UART_48MHZ | CLKCFG_BAUDDIV |
 						CLKCFG_PLL2VCO | CLKCFG_UARTCLKSEL,
@@ -747,6 +745,14 @@ static int __devinit pch_phub_probe(struct pci_dev *pdev,
 		chip->pch_opt_rom_start_address = PCH_PHUB_ROM_START_ADDR_EG20T;
 		chip->pch_mac_start_address = PCH_PHUB_MAC_START_ADDR_EG20T;
 	} else if (id->driver_data == 2) { /* ML7213 IOH */
+
+		/* Set the UART base clk rate to 192MHz */
+		pch_phub_read_modify_write_reg(chip,
+						(unsigned int)CLKCFG_REG_OFFSET,
+						CLKCFG_UART_48MHZ | CLKCFG_BAUDDIV |
+						CLKCFG_PLL2VCO | CLKCFG_UARTCLKSEL,
+						CLKCFG_UART_MASK);
+
 		retval = sysfs_create_bin_file(&pdev->dev.kobj, &pch_bin_attr);
 		if (retval)
 			goto err_sysfs_create;
@@ -804,6 +810,8 @@ static int __devinit pch_phub_probe(struct pci_dev *pdev,
 		chip->pch_mac_start_address = PCH_PHUB_MAC_START_ADDR_EG20T;
 	}
 
+	pr_info("PHUB controller: CLKCFG register is set to 0x%08x\n",
+		ioread32(chip->pch_phub_base_address + CLKCFG_REG_OFFSET));
 	chip->ioh_type = id->driver_data;
 	pci_set_drvdata(pdev, chip);
 
-- 
1.7.1


> 
> Is the pch_phub.c register manipulation required for proper related? It seems to
> work without touching those registers if I just force the clock.
> 
> The device I'm working with is EFI, and the dmi_get_system_info(DMI_BOARD_NAME)
> returns "(null)", so I can't use the same test to identify this board. Is there
> another common mechanism I might be able to use?
> 
> The following patch (by way of example, not meant for inclusion) gets things
> working for this particular board with this command line:
> 
> console=ttyPCH1,115200 pch_uart.clock_param=48000000
> 
> I believe the right thing to do here is to discover a way to identify the board
> and special case the clock as is done for the CM-iTC, but I would like to
> understand the purpose of the pch_phub register manipulation code. Does this
> make sense?
> 
> Thanks,
> 
> Darren
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