From 65a272642ce13aab911f68279c8994cde3282b0a Mon Sep 17 00:00:00 2001 From: Stephen Boyd Date: Fri, 18 May 2018 15:47:50 -0700 Subject: soc: qcom: geni: Make version macros simpler This macro doesn't work, because it hides a local variable inside of the macro to hold the version and that variable name is called 'ver' and 'version' sometimes. Let's change this to be more explicit. Introduce three macros for the major, minor, and step of the version, and require callers to pass the version in to get the part of the version out. This way we don't hide local variables inside macros and things are less evil overall. Cc: Karthikeyan Ramasubramanian Cc: Sagar Dharia Cc: Girish Mahadevan Signed-off-by: Stephen Boyd Reviewed-by: Douglas Anderson Reviewed-by: Bjorn Andersson Signed-off-by: Andy Gross --- include/linux/qcom-geni-se.h | 13 ++++--------- 1 file changed, 4 insertions(+), 9 deletions(-) diff --git a/include/linux/qcom-geni-se.h b/include/linux/qcom-geni-se.h index 5d6144977828..3bcd67fd5548 100644 --- a/include/linux/qcom-geni-se.h +++ b/include/linux/qcom-geni-se.h @@ -225,19 +225,14 @@ struct geni_se { #define HW_VER_MINOR_SHFT 16 #define HW_VER_STEP_MASK GENMASK(15, 0) +#define GENI_SE_VERSION_MAJOR(ver) ((ver & HW_VER_MAJOR_MASK) >> HW_VER_MAJOR_SHFT) +#define GENI_SE_VERSION_MINOR(ver) ((ver & HW_VER_MINOR_MASK) >> HW_VER_MINOR_SHFT) +#define GENI_SE_VERSION_STEP(ver) (ver & HW_VER_STEP_MASK) + #if IS_ENABLED(CONFIG_QCOM_GENI_SE) u32 geni_se_get_qup_hw_version(struct geni_se *se); -#define geni_se_get_wrapper_version(se, major, minor, step) do { \ - u32 ver; \ -\ - ver = geni_se_get_qup_hw_version(se); \ - major = (ver & HW_VER_MAJOR_MASK) >> HW_VER_MAJOR_SHFT; \ - minor = (ver & HW_VER_MINOR_MASK) >> HW_VER_MINOR_SHFT; \ - step = version & HW_VER_STEP_MASK; \ -} while (0) - /** * geni_se_read_proto() - Read the protocol configured for a serial engine * @se: Pointer to the concerned serial engine. -- cgit v1.2.3 From abc1c94471450de4fa085f5b1269837f97b1adc5 Mon Sep 17 00:00:00 2001 From: Douglas Anderson Date: Thu, 6 Sep 2018 15:49:05 -0700 Subject: soc: qcom: geni: Don't ignore clk_round_rate() errors in geni_se_clk_tbl_get() The function clk_round_rate() is defined to return a "long", not an "unsigned long". That's because it might return a negative error code. Change the call in geni_se_clk_tbl_get() to check for errors. While we're at it, get rid of a useless init of "freq". NOTE: overall the idea that we should iterate over clk_round_rate() to try to reconstruct a table already present in the clock driver is questionable. Specifically: - This method relies on "clk_round_rate()" rounding up. - This method only works if the table is sorted and has no duplicates. ...this patch doesn't try to fix those problems, it just makes the error handling more correct. Fixes: eddac5af0654 ("soc: qcom: Add GENI based QUP Wrapper driver") Signed-off-by: Douglas Anderson Reviewed-by: Matthias Kaehlcke Signed-off-by: Andy Gross --- drivers/soc/qcom/qcom-geni-se.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/soc/qcom/qcom-geni-se.c b/drivers/soc/qcom/qcom-geni-se.c index feed3db21c10..1b19b8428c4a 100644 --- a/drivers/soc/qcom/qcom-geni-se.c +++ b/drivers/soc/qcom/qcom-geni-se.c @@ -513,7 +513,7 @@ EXPORT_SYMBOL(geni_se_resources_on); */ int geni_se_clk_tbl_get(struct geni_se *se, unsigned long **tbl) { - unsigned long freq = 0; + long freq = 0; int i; if (se->clk_perf_tbl) { @@ -529,7 +529,7 @@ int geni_se_clk_tbl_get(struct geni_se *se, unsigned long **tbl) for (i = 0; i < MAX_CLK_PERF_LEVEL; i++) { freq = clk_round_rate(se->clk, freq + 1); - if (!freq || freq == se->clk_perf_tbl[i - 1]) + if (freq <= 0 || freq == se->clk_perf_tbl[i - 1]) break; se->clk_perf_tbl[i] = freq; } -- cgit v1.2.3 From 969fc78c37c3fb1363b4669a7d4df9c3804591e7 Mon Sep 17 00:00:00 2001 From: Douglas Anderson Date: Thu, 6 Sep 2018 15:49:06 -0700 Subject: soc: qcom: geni: geni_se_clk_freq_match() should always accept multiples The geni_se_clk_freq_match() has some strange semantics. Specifically it is defined with two modes: 1. It can find a clock that's an exact multiple of the requested rate 2. It can find a non-exact match but it can't handle multiples then ...but callers should always be able to handle a clock that is a multiple of the requested clock so mode #2 doesn't really make sense. Let's change the semantics so that the non-exact match can also accept multiples and then change the code to handle that. The only caller of this code is the unlanded SPI driver [1] which currently passes "exact = True", thus it should be safe to change the semantics in this way. ...and, in fact, the SPI driver should likely be modified to pass "exact = False" (with the new semantics) since that will allow it to work with SPI devices that request a clock rate that doesn't exactly match a rate we can make. [1] https://lkml.kernel.org/r/1535107336-2214-1-git-send-email-dkota@codeaurora.org Fixes: eddac5af0654 ("soc: qcom: Add GENI based QUP Wrapper driver") Signed-off-by: Douglas Anderson Reviewed-by: Matthias Kaehlcke Signed-off-by: Andy Gross --- drivers/soc/qcom/qcom-geni-se.c | 37 ++++++++++++++++++++++--------------- 1 file changed, 22 insertions(+), 15 deletions(-) diff --git a/drivers/soc/qcom/qcom-geni-se.c b/drivers/soc/qcom/qcom-geni-se.c index 1b19b8428c4a..ee89ffb6dde8 100644 --- a/drivers/soc/qcom/qcom-geni-se.c +++ b/drivers/soc/qcom/qcom-geni-se.c @@ -544,16 +544,17 @@ EXPORT_SYMBOL(geni_se_clk_tbl_get); * @se: Pointer to the concerned serial engine. * @req_freq: Requested clock frequency. * @index: Index of the resultant frequency in the table. - * @res_freq: Resultant frequency which matches or is closer to the - * requested frequency. + * @res_freq: Resultant frequency of the source clock. * @exact: Flag to indicate exact multiple requirement of the requested * frequency. * - * This function is called by the protocol drivers to determine the matching - * or exact multiple of the requested frequency, as provided by the serial - * engine clock in order to meet the performance requirements. If there is - * no matching or exact multiple of the requested frequency found, then it - * selects the closest floor frequency, if exact flag is not set. + * This function is called by the protocol drivers to determine the best match + * of the requested frequency as provided by the serial engine clock in order + * to meet the performance requirements. + * + * If we return success: + * - if @exact is true then @res_freq / == @req_freq + * - if @exact is false then @res_freq / <= @req_freq * * Return: 0 on success, standard Linux error codes on failure. */ @@ -564,6 +565,9 @@ int geni_se_clk_freq_match(struct geni_se *se, unsigned long req_freq, unsigned long *tbl; int num_clk_levels; int i; + unsigned long best_delta; + unsigned long new_delta; + unsigned int divider; num_clk_levels = geni_se_clk_tbl_get(se, &tbl); if (num_clk_levels < 0) @@ -572,18 +576,21 @@ int geni_se_clk_freq_match(struct geni_se *se, unsigned long req_freq, if (num_clk_levels == 0) return -EINVAL; - *res_freq = 0; + best_delta = ULONG_MAX; for (i = 0; i < num_clk_levels; i++) { - if (!(tbl[i] % req_freq)) { + divider = DIV_ROUND_UP(tbl[i], req_freq); + new_delta = req_freq - tbl[i] / divider; + if (new_delta < best_delta) { + /* We have a new best! */ *index = i; *res_freq = tbl[i]; - return 0; - } - if (!(*res_freq) || ((tbl[i] > *res_freq) && - (tbl[i] < req_freq))) { - *index = i; - *res_freq = tbl[i]; + /* If the new best is exact then we're done */ + if (new_delta == 0) + return 0; + + /* Record how close we got */ + best_delta = new_delta; } } -- cgit v1.2.3