| Message ID | 1585652976-17481-7-git-send-email-akashast@codeaurora.org |
|---|---|
| State | New |
| Headers | show |
| Series | Add interconnect support to QSPI and QUP drivers | expand |
Hi Matthias, On 4/1/2020 1:09 AM, Matthias Kaehlcke wrote: > Hi Akash, > > On Tue, Mar 31, 2020 at 04:39:34PM +0530, Akash Asthana wrote: >> Get the interconnect paths for Uart based Serial Engine device >> and vote according to the baud rate requirement of the driver. >> >> Signed-off-by: Akash Asthana <akashast@codeaurora.org> >> --- >> Changes in V2: >> - As per Bjorn's comment, removed se == NULL check from geni_serial_icc_get >> - As per Bjorn's comment, removed code to set se->icc_path* to NULL in failure >> - As per Bjorn's comment, introduced and using devm_of_icc_get API for getting >> path handle >> - As per Matthias comment, added error handling for icc_set_bw call >> >> Changes in V3: >> - As per Matthias comment, use common library APIs defined in geni-se >> driver for ICC functionality. >> >> drivers/tty/serial/qcom_geni_serial.c | 28 +++++++++++++++++++++++++--- >> 1 file changed, 25 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c >> index 8c5d97c..2befe72 100644 >> --- a/drivers/tty/serial/qcom_geni_serial.c >> +++ b/drivers/tty/serial/qcom_geni_serial.c >> @@ -965,6 +965,14 @@ static void qcom_geni_serial_set_termios(struct uart_port *uport, >> ser_clk_cfg = SER_CLK_EN; >> ser_clk_cfg |= clk_div << CLK_DIV_SHFT; >> >> + /* >> + * Bump up BW vote on CPU path as driver supports FIFO mode only. >> + * Assume peak_bw as twice of avg_bw. >> + */ >> + port->se.from_cpu.avg_bw = Bps_to_icc(baud); >> + port->se.from_cpu.peak_bw = Bps_to_icc(2 * baud); >> + geni_icc_vote_on(&port->se); >> + >> /* parity */ >> tx_trans_cfg = readl(uport->membase + SE_UART_TX_TRANS_CFG); >> tx_parity_cfg = readl(uport->membase + SE_UART_TX_PARITY_CFG); >> @@ -1202,11 +1210,14 @@ static void qcom_geni_serial_pm(struct uart_port *uport, >> if (old_state == UART_PM_STATE_UNDEFINED) >> old_state = UART_PM_STATE_OFF; >> >> - if (new_state == UART_PM_STATE_ON && old_state == UART_PM_STATE_OFF) >> + if (new_state == UART_PM_STATE_ON && old_state == UART_PM_STATE_OFF) { >> + geni_icc_vote_on(&port->se); >> geni_se_resources_on(&port->se); >> - else if (new_state == UART_PM_STATE_OFF && >> - old_state == UART_PM_STATE_ON) >> + } else if (new_state == UART_PM_STATE_OFF && >> + old_state == UART_PM_STATE_ON) { >> geni_se_resources_off(&port->se); >> + geni_icc_vote_off(&port->se); >> + } >> } >> >> static const struct uart_ops qcom_geni_console_pops = { >> @@ -1304,6 +1315,17 @@ static int qcom_geni_serial_probe(struct platform_device *pdev) >> return -ENOMEM; >> } >> >> + ret = geni_icc_get(&port->se, "qup-core", "qup-config", NULL); >> + if (ret) >> + return ret; >> + /* Set the bus quota to a reasonable value */ >> + port->se.to_core.avg_bw = console ? GENI_DEFAULT_BW : >> + Bps_to_icc(CORE_2X_50_MHZ); >> + port->se.to_core.peak_bw = console ? GENI_DEFAULT_BW : >> + Bps_to_icc(CORE_2X_100_MHZ); > I'm still unconvinced about the setting of the core bandwidth based on > whether the port is used as console or not. It could possibly break > consoles working at speeds > 115kbs and reserve more bandwidth than > necessary for ports with 'slow' devices. > > Why not scale the core bandwidth dynamically? You said earlier that there > is no clear/linear translation of port speed to bandwidth, but you could > use the same logic that is implicitly used here: > > if (baudrate <= 115200) { > avg_bw = GENI_DEFAULT_BW; > peak_bw = GENI_DEFAULT_BW; > } else { > avg_bw = Bps_to_icc(CORE_2X_50_MHZ); > peak_bw = Bps_to_icc(CORE_2X_100_MHZ); > } > > This would be more robust, power efficient and future readers of the > code don't have to wonder "why is the console special?" when our > discussions on this will be long forgotten. Okay, I will add this piece of code in set_termios call of the driver because I don't have baudrate information during probe. It covers the console case mentioned in probe function. Regards, Akash
diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c index 8c5d97c..2befe72 100644 --- a/drivers/tty/serial/qcom_geni_serial.c +++ b/drivers/tty/serial/qcom_geni_serial.c @@ -965,6 +965,14 @@ static void qcom_geni_serial_set_termios(struct uart_port *uport, ser_clk_cfg = SER_CLK_EN; ser_clk_cfg |= clk_div << CLK_DIV_SHFT; + /* + * Bump up BW vote on CPU path as driver supports FIFO mode only. + * Assume peak_bw as twice of avg_bw. + */ + port->se.from_cpu.avg_bw = Bps_to_icc(baud); + port->se.from_cpu.peak_bw = Bps_to_icc(2 * baud); + geni_icc_vote_on(&port->se); + /* parity */ tx_trans_cfg = readl(uport->membase + SE_UART_TX_TRANS_CFG); tx_parity_cfg = readl(uport->membase + SE_UART_TX_PARITY_CFG); @@ -1202,11 +1210,14 @@ static void qcom_geni_serial_pm(struct uart_port *uport, if (old_state == UART_PM_STATE_UNDEFINED) old_state = UART_PM_STATE_OFF; - if (new_state == UART_PM_STATE_ON && old_state == UART_PM_STATE_OFF) + if (new_state == UART_PM_STATE_ON && old_state == UART_PM_STATE_OFF) { + geni_icc_vote_on(&port->se); geni_se_resources_on(&port->se); - else if (new_state == UART_PM_STATE_OFF && - old_state == UART_PM_STATE_ON) + } else if (new_state == UART_PM_STATE_OFF && + old_state == UART_PM_STATE_ON) { geni_se_resources_off(&port->se); + geni_icc_vote_off(&port->se); + } } static const struct uart_ops qcom_geni_console_pops = { @@ -1304,6 +1315,17 @@ static int qcom_geni_serial_probe(struct platform_device *pdev) return -ENOMEM; } + ret = geni_icc_get(&port->se, "qup-core", "qup-config", NULL); + if (ret) + return ret; + /* Set the bus quota to a reasonable value */ + port->se.to_core.avg_bw = console ? GENI_DEFAULT_BW : + Bps_to_icc(CORE_2X_50_MHZ); + port->se.to_core.peak_bw = console ? GENI_DEFAULT_BW : + Bps_to_icc(CORE_2X_100_MHZ); + port->se.from_cpu.avg_bw = GENI_DEFAULT_BW; + port->se.from_cpu.peak_bw = GENI_DEFAULT_BW; + port->name = devm_kasprintf(uport->dev, GFP_KERNEL, "qcom_geni_serial_%s%d", uart_console(uport) ? "console" : "uart", uport->line);
Get the interconnect paths for Uart based Serial Engine device and vote according to the baud rate requirement of the driver. Signed-off-by: Akash Asthana <akashast@codeaurora.org> --- Changes in V2: - As per Bjorn's comment, removed se == NULL check from geni_serial_icc_get - As per Bjorn's comment, removed code to set se->icc_path* to NULL in failure - As per Bjorn's comment, introduced and using devm_of_icc_get API for getting path handle - As per Matthias comment, added error handling for icc_set_bw call Changes in V3: - As per Matthias comment, use common library APIs defined in geni-se driver for ICC functionality. drivers/tty/serial/qcom_geni_serial.c | 28 +++++++++++++++++++++++++--- 1 file changed, 25 insertions(+), 3 deletions(-)