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authorRoger Quadros <rogerq@kernel.org>2022-10-20 16:30:49 +0300
committerTom Rini <trini@konsulko.com>2022-10-26 15:21:12 -0400
commit9b0b5648d6e4d89aa594022e48894e811c250d5f (patch)
treeb4ace98fe43682d20639adab97778dca140149c2
parent37d6d1645a33e410ca0fd9b56c03426b646df1fd (diff)
downloadu-boot-9b0b5648d6e4d89aa594022e48894e811c250d5f.tar.gz
memory: Add TI GPMC driver
The GPMC is a unified memory controller dedicated for interfacing with external memory devices like - Asynchronous SRAM-like memories and ASICs - Asynchronous, synchronous, and page mode burst NOR flash - NAND flash - Pseudo-SRAM devices This driver will take care of setting up the GPMC based on the settings specified in the Device tree and then probe its children. Signed-off-by: Roger Quadros <rogerq@kernel.org>
-rw-r--r--drivers/memory/Kconfig19
-rw-r--r--drivers/memory/Makefile1
-rw-r--r--drivers/memory/ti-gpmc.c1240
-rw-r--r--drivers/memory/ti-gpmc.h298
-rw-r--r--include/linux/mtd/omap_gpmc.h3
5 files changed, 1561 insertions, 0 deletions
diff --git a/drivers/memory/Kconfig b/drivers/memory/Kconfig
index c621f5bba3..56b89f17be 100644
--- a/drivers/memory/Kconfig
+++ b/drivers/memory/Kconfig
@@ -41,4 +41,23 @@ config TI_AEMIF
of 256M bytes of any of these memories can be accessed at a given
time via four chip selects with 64M byte access per chip select.
+config TI_GPMC
+ bool "Texas Instruments GPMC driver"
+ depends on ARCH_OMAP2PLUS || ARCH_KEYSTONE || ARCH_K3
+ depends on MEMORY && CLK && OF_CONTROL
+ help
+ This driver is for the General Purpose Memory Controller (GPMC)
+ present on Texas Instruments SoCs (e.g. OMAP2+). GPMC allows
+ interfacing to a variety of asynchronous as well as synchronous
+ memory drives like NOR, NAND, OneNAND, SRAM.
+
+if TI_GPMC
+config TI_GPMC_DEBUG
+ bool "Debug Texas Instruments GPMC timings"
+ default n
+ help
+ Enable this to print GPMC timings before and after the GPMC registers
+ are programmed. This should not be left enabled on production systems.
+endif
+
endmenu
diff --git a/drivers/memory/Makefile b/drivers/memory/Makefile
index b27f701865..2b196d78c0 100644
--- a/drivers/memory/Makefile
+++ b/drivers/memory/Makefile
@@ -3,3 +3,4 @@ obj-$(CONFIG_MEMORY) += memory-uclass.o
obj-$(CONFIG_SANDBOX_MEMORY) += memory-sandbox.o
obj-$(CONFIG_STM32_FMC2_EBI) += stm32-fmc2-ebi.o
obj-$(CONFIG_TI_AEMIF) += ti-aemif.o
+obj-$(CONFIG_TI_GPMC) += ti-gpmc.o
diff --git a/drivers/memory/ti-gpmc.c b/drivers/memory/ti-gpmc.c
new file mode 100644
index 0000000000..f511a529b1
--- /dev/null
+++ b/drivers/memory/ti-gpmc.c
@@ -0,0 +1,1240 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Texas Instruments GPMC Driver
+ *
+ * Copyright (C) 2021 Texas Instruments Incorporated - http://www.ti.com/
+ */
+
+#include <asm/io.h>
+#include <asm/arch/sys_proto.h>
+#include <clk.h>
+#include <common.h>
+#include <dm.h>
+#include <dm/device-internal.h>
+#include <dm/device_compat.h>
+#include <dm/devres.h>
+#include <dm/lists.h>
+#include <linux/mtd/omap_gpmc.h>
+#include <linux/ioport.h>
+#include <linux/io.h>
+#include "ti-gpmc.h"
+
+enum gpmc_clk_domain {
+ GPMC_CD_FCLK,
+ GPMC_CD_CLK
+};
+
+struct gpmc_cs_data {
+ const char *name;
+#define GPMC_CS_RESERVED BIT(0)
+ u32 flags;
+};
+
+struct ti_gpmc {
+ void __iomem *base;
+ u32 cs_num;
+ u32 nr_waitpins;
+ struct clk *l3_clk;
+ u32 capability_flags;
+ struct resource data;
+};
+
+static struct gpmc_cs_data gpmc_cs[GPMC_CS_NUM];
+static unsigned int gpmc_cs_num = GPMC_CS_NUM;
+static unsigned int gpmc_nr_waitpins;
+static unsigned int gpmc_capability;
+static void __iomem *gpmc_base;
+static struct clk *gpmc_l3_clk;
+
+/* Public, as required by nand/raw/omap_gpmc.c */
+const struct gpmc *gpmc_cfg;
+
+/*
+ * The first 1MB of GPMC address space is typically mapped to
+ * the internal ROM. Never allocate the first page, to
+ * facilitate bug detection; even if we didn't boot from ROM.
+ * As GPMC minimum partition size is 16MB we can only start from
+ * there.
+ */
+#define GPMC_MEM_START 0x1000000
+#define GPMC_MEM_END 0x3FFFFFFF
+
+static void gpmc_write_reg(int idx, u32 val)
+{
+ writel_relaxed(val, gpmc_base + idx);
+}
+
+static u32 gpmc_read_reg(int idx)
+{
+ return readl_relaxed(gpmc_base + idx);
+}
+
+static void gpmc_cs_write_reg(int cs, int idx, u32 val)
+{
+ void __iomem *reg_addr;
+
+ reg_addr = gpmc_base + GPMC_CS0_OFFSET + (cs * GPMC_CS_SIZE) + idx;
+ writel_relaxed(val, reg_addr);
+}
+
+static u32 gpmc_cs_read_reg(int cs, int idx)
+{
+ void __iomem *reg_addr;
+
+ reg_addr = gpmc_base + GPMC_CS0_OFFSET + (cs * GPMC_CS_SIZE) + idx;
+ return readl_relaxed(reg_addr);
+}
+
+static unsigned long gpmc_get_fclk_period(void)
+{
+ unsigned long rate = clk_get_rate(gpmc_l3_clk);
+
+ rate /= 1000;
+ rate = 1000000000 / rate; /* In picoseconds */
+
+ return rate;
+}
+
+/**
+ * gpmc_get_clk_period - get period of selected clock domain in ps
+ * @cs: Chip Select Region.
+ * @cd: Clock Domain.
+ *
+ * GPMC_CS_CONFIG1 GPMCFCLKDIVIDER for cs has to be setup
+ * prior to calling this function with GPMC_CD_CLK.
+ */
+static unsigned long gpmc_get_clk_period(int cs, enum gpmc_clk_domain cd)
+{
+ unsigned long tick_ps = gpmc_get_fclk_period();
+ u32 l;
+ int div;
+
+ switch (cd) {
+ case GPMC_CD_CLK:
+ /* get current clk divider */
+ l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG1);
+ div = (l & 0x03) + 1;
+ /* get GPMC_CLK period */
+ tick_ps *= div;
+ break;
+ case GPMC_CD_FCLK:
+ default:
+ break;
+ }
+
+ return tick_ps;
+}
+
+static unsigned int gpmc_ns_to_clk_ticks(unsigned int time_ns, int cs,
+ enum gpmc_clk_domain cd)
+{
+ unsigned long tick_ps;
+
+ /* Calculate in picosecs to yield more exact results */
+ tick_ps = gpmc_get_clk_period(cs, cd);
+
+ return (time_ns * 1000 + tick_ps - 1) / tick_ps;
+}
+
+static unsigned int gpmc_ns_to_ticks(unsigned int time_ns)
+{
+ return gpmc_ns_to_clk_ticks(time_ns, /* any CS */ 0, GPMC_CD_FCLK);
+}
+
+static unsigned int gpmc_ps_to_ticks(unsigned int time_ps)
+{
+ unsigned long tick_ps;
+
+ /* Calculate in picosecs to yield more exact results */
+ tick_ps = gpmc_get_fclk_period();
+
+ return (time_ps + tick_ps - 1) / tick_ps;
+}
+
+static __maybe_unused unsigned int gpmc_clk_ticks_to_ns(unsigned int ticks, int cs,
+ enum gpmc_clk_domain cd)
+{
+ return ticks * gpmc_get_clk_period(cs, cd) / 1000;
+}
+
+static inline void gpmc_cs_modify_reg(int cs, int reg, u32 mask, bool value)
+{
+ u32 l;
+
+ l = gpmc_cs_read_reg(cs, reg);
+ if (value)
+ l |= mask;
+ else
+ l &= ~mask;
+ gpmc_cs_write_reg(cs, reg, l);
+}
+
+static void gpmc_cs_bool_timings(int cs, const struct gpmc_bool_timings *p)
+{
+ gpmc_cs_modify_reg(cs, GPMC_CS_CONFIG1,
+ GPMC_CONFIG1_TIME_PARA_GRAN,
+ p->time_para_granularity);
+ gpmc_cs_modify_reg(cs, GPMC_CS_CONFIG2,
+ GPMC_CONFIG2_CSEXTRADELAY, p->cs_extra_delay);
+ gpmc_cs_modify_reg(cs, GPMC_CS_CONFIG3,
+ GPMC_CONFIG3_ADVEXTRADELAY, p->adv_extra_delay);
+ gpmc_cs_modify_reg(cs, GPMC_CS_CONFIG4,
+ GPMC_CONFIG4_OEEXTRADELAY, p->oe_extra_delay);
+ gpmc_cs_modify_reg(cs, GPMC_CS_CONFIG4,
+ GPMC_CONFIG4_WEEXTRADELAY, p->we_extra_delay);
+ gpmc_cs_modify_reg(cs, GPMC_CS_CONFIG6,
+ GPMC_CONFIG6_CYCLE2CYCLESAMECSEN,
+ p->cycle2cyclesamecsen);
+ gpmc_cs_modify_reg(cs, GPMC_CS_CONFIG6,
+ GPMC_CONFIG6_CYCLE2CYCLEDIFFCSEN,
+ p->cycle2cyclediffcsen);
+}
+
+#if IS_ENABLED(CONFIG_TI_GPMC_DEBUG)
+/**
+ * get_gpmc_timing_reg - read a timing parameter and print DTS settings for it.
+ * @cs: Chip Select Region
+ * @reg: GPMC_CS_CONFIGn register offset.
+ * @st_bit: Start Bit
+ * @end_bit: End Bit. Must be >= @st_bit.
+ * @max: Maximum parameter value (before optional @shift).
+ * If 0, maximum is as high as @st_bit and @end_bit allow.
+ * @name: DTS node name, w/o "gpmc,"
+ * @cd: Clock Domain of timing parameter.
+ * @shift: Parameter value left shifts @shift, which is then printed instead of value.
+ * @raw: Raw Format Option.
+ * raw format: gpmc,name = <value>
+ * tick format: gpmc,name = <value> /&zwj;* x ns -- y ns; x ticks *&zwj;/
+ * Where x ns -- y ns result in the same tick value.
+ * When @max is exceeded, "invalid" is printed inside comment.
+ * @noval: Parameter values equal to 0 are not printed.
+ * @return: Specified timing parameter (after optional @shift).
+ *
+ */
+static int get_gpmc_timing_reg(/* timing specifiers */
+ int cs, int reg, int st_bit, int end_bit, int max,
+ const char *name, const enum gpmc_clk_domain cd,
+ /* value transform */
+ int shift,
+ /* format specifiers */
+ bool raw, bool noval)
+{
+ u32 l;
+ int nr_bits;
+ int mask;
+ bool invalid;
+
+ l = gpmc_cs_read_reg(cs, reg);
+ nr_bits = end_bit - st_bit + 1;
+ mask = (1 << nr_bits) - 1;
+ l = (l >> st_bit) & mask;
+ if (!max)
+ max = mask;
+ invalid = l > max;
+ if (shift)
+ l = (shift << l);
+ if (noval && l == 0)
+ return 0;
+ if (!raw) {
+ /* DTS tick format for timings in ns */
+ unsigned int time_ns;
+ unsigned int time_ns_min = 0;
+
+ if (l)
+ time_ns_min = gpmc_clk_ticks_to_ns(l - 1, cs, cd) + 1;
+ time_ns = gpmc_clk_ticks_to_ns(l, cs, cd);
+ pr_info("gpmc,%s = <%u>; /* %u ns - %u ns; %i ticks%s*/\n",
+ name, time_ns, time_ns_min, time_ns, l,
+ invalid ? "; invalid " : " ");
+ } else {
+ /* raw format */
+ pr_info("gpmc,%s = <%u>;%s\n", name, l,
+ invalid ? " /* invalid */" : "");
+ }
+
+ return l;
+}
+
+#define GPMC_PRINT_CONFIG(cs, config) \
+ pr_info("CS%i %s: 0x%08x\n", cs, #config, \
+ gpmc_cs_read_reg(cs, config))
+#define GPMC_GET_RAW(reg, st, end, field) \
+ get_gpmc_timing_reg(cs, (reg), (st), (end), 0, field, GPMC_CD_FCLK, 0, 1, 0)
+#define GPMC_GET_RAW_MAX(reg, st, end, max, field) \
+ get_gpmc_timing_reg(cs, (reg), (st), (end), (max), field, GPMC_CD_FCLK, 0, 1, 0)
+#define GPMC_GET_RAW_BOOL(reg, st, end, field) \
+ get_gpmc_timing_reg(cs, (reg), (st), (end), 0, field, GPMC_CD_FCLK, 0, 1, 1)
+#define GPMC_GET_RAW_SHIFT_MAX(reg, st, end, shift, max, field) \
+ get_gpmc_timing_reg(cs, (reg), (st), (end), (max), field, GPMC_CD_FCLK, (shift), 1, 1)
+#define GPMC_GET_TICKS(reg, st, end, field) \
+ get_gpmc_timing_reg(cs, (reg), (st), (end), 0, field, GPMC_CD_FCLK, 0, 0, 0)
+#define GPMC_GET_TICKS_CD(reg, st, end, field, cd) \
+ get_gpmc_timing_reg(cs, (reg), (st), (end), 0, field, (cd), 0, 0, 0)
+#define GPMC_GET_TICKS_CD_MAX(reg, st, end, max, field, cd) \
+ get_gpmc_timing_reg(cs, (reg), (st), (end), (max), field, (cd), 0, 0, 0)
+
+static void gpmc_show_regs(int cs, const char *desc)
+{
+ pr_info("gpmc cs%i %s:\n", cs, desc);
+ GPMC_PRINT_CONFIG(cs, GPMC_CS_CONFIG1);
+ GPMC_PRINT_CONFIG(cs, GPMC_CS_CONFIG2);
+ GPMC_PRINT_CONFIG(cs, GPMC_CS_CONFIG3);
+ GPMC_PRINT_CONFIG(cs, GPMC_CS_CONFIG4);
+ GPMC_PRINT_CONFIG(cs, GPMC_CS_CONFIG5);
+ GPMC_PRINT_CONFIG(cs, GPMC_CS_CONFIG6);
+}
+
+/*
+ * Note that gpmc,wait-pin handing wrongly assumes bit 8 is available,
+ * see commit c9fb809.
+ */
+static void gpmc_cs_show_timings(int cs, const char *desc)
+{
+ gpmc_show_regs(cs, desc);
+
+ pr_info("gpmc cs%i access configuration:\n", cs);
+ GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG1, 4, 4, "time-para-granularity");
+ GPMC_GET_RAW(GPMC_CS_CONFIG1, 8, 9, "mux-add-data");
+ GPMC_GET_RAW_SHIFT_MAX(GPMC_CS_CONFIG1, 12, 13, 1,
+ GPMC_CONFIG1_DEVICESIZE_MAX, "device-width");
+ GPMC_GET_RAW(GPMC_CS_CONFIG1, 16, 17, "wait-pin");
+ GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG1, 21, 21, "wait-on-write");
+ GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG1, 22, 22, "wait-on-read");
+ GPMC_GET_RAW_SHIFT_MAX(GPMC_CS_CONFIG1, 23, 24, 4,
+ GPMC_CONFIG1_ATTACHEDDEVICEPAGELENGTH_MAX,
+ "burst-length");
+ GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG1, 27, 27, "sync-write");
+ GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG1, 28, 28, "burst-write");
+ GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG1, 29, 29, "gpmc,sync-read");
+ GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG1, 30, 30, "burst-read");
+ GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG1, 31, 31, "burst-wrap");
+
+ GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG2, 7, 7, "cs-extra-delay");
+
+ GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG3, 7, 7, "adv-extra-delay");
+
+ GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG4, 23, 23, "we-extra-delay");
+ GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG4, 7, 7, "oe-extra-delay");
+
+ GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG6, 7, 7, "cycle2cycle-samecsen");
+ GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG6, 6, 6, "cycle2cycle-diffcsen");
+
+ pr_info("gpmc cs%i timings configuration:\n", cs);
+ GPMC_GET_TICKS(GPMC_CS_CONFIG2, 0, 3, "cs-on-ns");
+ GPMC_GET_TICKS(GPMC_CS_CONFIG2, 8, 12, "cs-rd-off-ns");
+ GPMC_GET_TICKS(GPMC_CS_CONFIG2, 16, 20, "cs-wr-off-ns");
+
+ GPMC_GET_TICKS(GPMC_CS_CONFIG3, 0, 3, "adv-on-ns");
+ GPMC_GET_TICKS(GPMC_CS_CONFIG3, 8, 12, "adv-rd-off-ns");
+ GPMC_GET_TICKS(GPMC_CS_CONFIG3, 16, 20, "adv-wr-off-ns");
+ if (gpmc_capability & GPMC_HAS_MUX_AAD) {
+ GPMC_GET_TICKS(GPMC_CS_CONFIG3, 4, 6, "adv-aad-mux-on-ns");
+ GPMC_GET_TICKS(GPMC_CS_CONFIG3, 24, 26,
+ "adv-aad-mux-rd-off-ns");
+ GPMC_GET_TICKS(GPMC_CS_CONFIG3, 28, 30,
+ "adv-aad-mux-wr-off-ns");
+ }
+
+ GPMC_GET_TICKS(GPMC_CS_CONFIG4, 0, 3, "oe-on-ns");
+ GPMC_GET_TICKS(GPMC_CS_CONFIG4, 8, 12, "oe-off-ns");
+ if (gpmc_capability & GPMC_HAS_MUX_AAD) {
+ GPMC_GET_TICKS(GPMC_CS_CONFIG4, 4, 6, "oe-aad-mux-on-ns");
+ GPMC_GET_TICKS(GPMC_CS_CONFIG4, 13, 15, "oe-aad-mux-off-ns");
+ }
+ GPMC_GET_TICKS(GPMC_CS_CONFIG4, 16, 19, "we-on-ns");
+ GPMC_GET_TICKS(GPMC_CS_CONFIG4, 24, 28, "we-off-ns");
+
+ GPMC_GET_TICKS(GPMC_CS_CONFIG5, 0, 4, "rd-cycle-ns");
+ GPMC_GET_TICKS(GPMC_CS_CONFIG5, 8, 12, "wr-cycle-ns");
+ GPMC_GET_TICKS(GPMC_CS_CONFIG5, 16, 20, "access-ns");
+
+ GPMC_GET_TICKS(GPMC_CS_CONFIG5, 24, 27, "page-burst-access-ns");
+
+ GPMC_GET_TICKS(GPMC_CS_CONFIG6, 0, 3, "bus-turnaround-ns");
+ GPMC_GET_TICKS(GPMC_CS_CONFIG6, 8, 11, "cycle2cycle-delay-ns");
+
+ GPMC_GET_TICKS_CD_MAX(GPMC_CS_CONFIG1, 18, 19,
+ GPMC_CONFIG1_WAITMONITORINGTIME_MAX,
+ "wait-monitoring-ns", GPMC_CD_CLK);
+ GPMC_GET_TICKS_CD_MAX(GPMC_CS_CONFIG1, 25, 26,
+ GPMC_CONFIG1_CLKACTIVATIONTIME_MAX,
+ "clk-activation-ns", GPMC_CD_FCLK);
+
+ GPMC_GET_TICKS(GPMC_CS_CONFIG6, 16, 19, "wr-data-mux-bus-ns");
+ GPMC_GET_TICKS(GPMC_CS_CONFIG6, 24, 28, "wr-access-ns");
+}
+#else
+static inline void gpmc_cs_show_timings(int cs, const char *desc)
+{
+}
+#endif
+
+/**
+ * set_gpmc_timing_reg - set a single timing parameter for Chip Select Region.
+ * Caller is expected to have initialized CONFIG1 GPMCFCLKDIVIDER
+ * prior to calling this function with @cd equal to GPMC_CD_CLK.
+ *
+ * @cs: Chip Select Region.
+ * @reg: GPMC_CS_CONFIGn register offset.
+ * @st_bit: Start Bit
+ * @end_bit: End Bit. Must be >= @st_bit.
+ * @max: Maximum parameter value.
+ * If 0, maximum is as high as @st_bit and @end_bit allow.
+ * @time: Timing parameter in ns.
+ * @cd: Timing parameter clock domain.
+ * @name: Timing parameter name.
+ * @return: 0 on success, -1 on error.
+ */
+static int set_gpmc_timing_reg(int cs, int reg, int st_bit, int end_bit, int max,
+ int time, enum gpmc_clk_domain cd, const char *name)
+{
+ u32 l;
+ int ticks, mask, nr_bits;
+
+ if (time == 0)
+ ticks = 0;
+ else
+ ticks = gpmc_ns_to_clk_ticks(time, cs, cd);
+ nr_bits = end_bit - st_bit + 1;
+ mask = (1 << nr_bits) - 1;
+
+ if (!max)
+ max = mask;
+
+ if (ticks > max) {
+ pr_err("%s: GPMC CS%d: %s %d ns, %d ticks > %d ticks\n",
+ __func__, cs, name, time, ticks, max);
+
+ return -1;
+ }
+
+ l = gpmc_cs_read_reg(cs, reg);
+ if (IS_ENABLED(CONFIG_TI_GPMC_DEBUG)) {
+ pr_info("GPMC CS%d: %-17s: %3d ticks, %3lu ns (was %3i ticks) %3d ns\n",
+ cs, name, ticks, gpmc_get_clk_period(cs, cd) * ticks / 1000,
+ (l >> st_bit) & mask, time);
+ }
+
+ l &= ~(mask << st_bit);
+ l |= ticks << st_bit;
+ gpmc_cs_write_reg(cs, reg, l);
+
+ return 0;
+}
+
+/**
+ * gpmc_calc_waitmonitoring_divider - calculate proper GPMCFCLKDIVIDER based on WAITMONITORINGTIME
+ * WAITMONITORINGTIME will be _at least_ as long as desired, i.e.
+ * read --> don't sample bus too early
+ * write --> data is longer on bus
+ *
+ * Formula:
+ * gpmc_clk_div + 1 = ceil(ceil(waitmonitoringtime_ns / gpmc_fclk_ns)
+ * / waitmonitoring_ticks)
+ * WAITMONITORINGTIME resulting in 0 or 1 tick with div = 1 are caught by
+ * div <= 0 check.
+ *
+ * @wait_monitoring: WAITMONITORINGTIME in ns.
+ * @return: -1 on failure to scale, else proper divider > 0.
+ */
+static int gpmc_calc_waitmonitoring_divider(unsigned int wait_monitoring)
+{
+ int div = gpmc_ns_to_ticks(wait_monitoring);
+
+ div += GPMC_CONFIG1_WAITMONITORINGTIME_MAX - 1;
+ div /= GPMC_CONFIG1_WAITMONITORINGTIME_MAX;
+
+ if (div > 4)
+ return -1;
+ if (div <= 0)
+ div = 1;
+
+ return div;
+}
+
+/**
+ * gpmc_calc_divider - calculate GPMC_FCLK divider for sync_clk GPMC_CLK period.
+ * @sync_clk: GPMC_CLK period in ps.
+ * @return: Returns at least 1 if GPMC_FCLK can be divided to GPMC_CLK.
+ * Else, returns -1.
+ */
+static int gpmc_calc_divider(unsigned int sync_clk)
+{
+ int div = gpmc_ps_to_ticks(sync_clk);
+
+ if (div > 4)
+ return -1;
+ if (div <= 0)
+ div = 1;
+
+ return div;
+}
+
+/**
+ * gpmc_cs_set_timings - program timing parameters for Chip Select Region.
+ * @cs: Chip Select Region.
+ * @t: GPMC timing parameters.
+ * @s: GPMC timing settings.
+ * @return: 0 on success, -1 on error.
+ */
+static int gpmc_cs_set_timings(int cs, const struct gpmc_timings *t,
+ const struct gpmc_settings *s)
+{
+ int div, ret;
+ u32 l;
+
+ div = gpmc_calc_divider(t->sync_clk);
+ if (div < 0)
+ return -EINVAL;
+
+ /*
+ * See if we need to change the divider for waitmonitoringtime.
+ *
+ * Calculate GPMCFCLKDIVIDER independent of gpmc,sync-clk-ps in DT for
+ * pure asynchronous accesses, i.e. both read and write asynchronous.
+ * However, only do so if WAITMONITORINGTIME is actually used, i.e.
+ * either WAITREADMONITORING or WAITWRITEMONITORING is set.
+ *
+ * This statement must not change div to scale async WAITMONITORINGTIME
+ * to protect mixed synchronous and asynchronous accesses.
+ *
+ * We raise an error later if WAITMONITORINGTIME does not fit.
+ */
+ if (!s->sync_read && !s->sync_write &&
+ (s->wait_on_read || s->wait_on_write)
+ ) {
+ div = gpmc_calc_waitmonitoring_divider(t->wait_monitoring);
+ if (div < 0) {
+ pr_err("%s: waitmonitoringtime %3d ns too large for greatest gpmcfclkdivider.\n",
+ __func__,
+ t->wait_monitoring
+ );
+ return -ENXIO;
+ }
+ }
+
+ ret = 0;
+ ret |= set_gpmc_timing_reg(cs, GPMC_CS_CONFIG2, 0, 3, 0, t->cs_on,
+ GPMC_CD_FCLK, "cs_on");
+ ret |= set_gpmc_timing_reg(cs, GPMC_CS_CONFIG2, 8, 12, 0, t->cs_rd_off,
+ GPMC_CD_FCLK, "cs_rd_off");
+ ret |= set_gpmc_timing_reg(cs, GPMC_CS_CONFIG2, 16, 20, 0, t->cs_wr_off,
+ GPMC_CD_FCLK, "cs_wr_off");
+ if (ret)
+ return -ENXIO;
+
+ ret |= set_gpmc_timing_reg(cs, GPMC_CS_CONFIG3, 0, 3, 0, t->adv_on,
+ GPMC_CD_FCLK, "adv_on");
+ ret |= set_gpmc_timing_reg(cs, GPMC_CS_CONFIG3, 8, 12, 0, t->adv_rd_off,
+ GPMC_CD_FCLK, "adv_rd_off");
+ ret |= set_gpmc_timing_reg(cs, GPMC_CS_CONFIG3, 16, 20, 0, t->adv_wr_off,
+ GPMC_CD_FCLK, "adv_wr_off");
+ if (ret)
+ return -ENXIO;
+
+ if (gpmc_capability & GPMC_HAS_MUX_AAD) {
+ ret |= set_gpmc_timing_reg(cs, GPMC_CS_CONFIG3, 4, 6, 0,
+ t->adv_aad_mux_on, GPMC_CD_FCLK,
+ "adv_aad_mux_on");
+ ret |= set_gpmc_timing_reg(cs, GPMC_CS_CONFIG3, 24, 26, 0,
+ t->adv_aad_mux_rd_off, GPMC_CD_FCLK,
+ "adv_aad_mux_rd_off");
+ ret |= set_gpmc_timing_reg(cs, GPMC_CS_CONFIG3, 28, 30, 0,
+ t->adv_aad_mux_wr_off, GPMC_CD_FCLK,
+ "adv_aad_mux_wr_off");
+ if (ret)
+ return -ENXIO;
+ }
+
+ ret |= set_gpmc_timing_reg(cs, GPMC_CS_CONFIG4, 0, 3, 0, t->oe_on,
+ GPMC_CD_FCLK, "oe_on");
+ ret |= set_gpmc_timing_reg(cs, GPMC_CS_CONFIG4, 8, 12, 0, t->oe_off,
+ GPMC_CD_FCLK, "oe_off");
+ if (gpmc_capability & GPMC_HAS_MUX_AAD) {
+ ret |= set_gpmc_timing_reg(cs, GPMC_CS_CONFIG4, 4, 6, 0,
+ t->oe_aad_mux_on, GPMC_CD_FCLK,
+ "oe_aad_mux_on");
+ ret |= set_gpmc_timing_reg(cs, GPMC_CS_CONFIG4, 13, 15, 0,
+ t->oe_aad_mux_off, GPMC_CD_FCLK,
+ "oe_aad_mux_off");
+ }
+ ret |= set_gpmc_timing_reg(cs, GPMC_CS_CONFIG4, 16, 19, 0, t->we_on,
+ GPMC_CD_FCLK, "we_on");
+ ret |= set_gpmc_timing_reg(cs, GPMC_CS_CONFIG4, 24, 28, 0, t->we_off,
+ GPMC_CD_FCLK, "we_off");
+ if (ret)
+ return -ENXIO;
+
+ ret |= set_gpmc_timing_reg(cs, GPMC_CS_CONFIG5, 0, 4, 0, t->rd_cycle,
+ GPMC_CD_FCLK, "rd_cycle");
+ ret |= set_gpmc_timing_reg(cs, GPMC_CS_CONFIG5, 8, 12, 0, t->wr_cycle,
+ GPMC_CD_FCLK, "wr_cycle");
+ ret |= set_gpmc_timing_reg(cs, GPMC_CS_CONFIG5, 16, 20, 0, t->access,
+ GPMC_CD_FCLK, "access");
+ ret |= set_gpmc_timing_reg(cs, GPMC_CS_CONFIG5, 24, 27, 0,
+ t->page_burst_access, GPMC_CD_FCLK,
+ "page_burst_access");
+ if (ret)
+ return -ENXIO;
+
+ ret |= set_gpmc_timing_reg(cs, GPMC_CS_CONFIG6, 0, 3, 0,
+ t->bus_turnaround, GPMC_CD_FCLK,
+ "bus_turnaround");
+ ret |= set_gpmc_timing_reg(cs, GPMC_CS_CONFIG6, 8, 11, 0,
+ t->cycle2cycle_delay, GPMC_CD_FCLK,
+ "cycle2cycle_delay");
+ if (ret)
+ return -ENXIO;
+
+ if (gpmc_capability & GPMC_HAS_WR_DATA_MUX_BUS) {
+ ret |= set_gpmc_timing_reg(cs, GPMC_CS_CONFIG6, 16, 19, 0,
+ t->wr_data_mux_bus, GPMC_CD_FCLK,
+ "wr_data_mux_bus");
+ if (ret)
+ return -ENXIO;
+ }
+ if (gpmc_capability & GPMC_HAS_WR_ACCESS) {
+ ret |= set_gpmc_timing_reg(cs, GPMC_CS_CONFIG6, 24, 28, 0,
+ t->wr_access, GPMC_CD_FCLK,
+ "wr_access");
+ if (ret)
+ return -ENXIO;
+ }
+
+ l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG1);
+ l &= ~0x03;
+ l |= (div - 1);
+ gpmc_cs_write_reg(cs, GPMC_CS_CONFIG1, l);
+
+ ret = 0;
+ ret |= set_gpmc_timing_reg(cs, GPMC_CS_CONFIG1, 18, 19,
+ GPMC_CONFIG1_WAITMONITORINGTIME_MAX,
+ t->wait_monitoring, GPMC_CD_CLK,
+ "wait_monitoring");
+ ret |= set_gpmc_timing_reg(cs, GPMC_CS_CONFIG1, 25, 26,
+ GPMC_CONFIG1_CLKACTIVATIONTIME_MAX,
+ t->clk_activation, GPMC_CD_FCLK,
+ "clk_activation");
+ if (ret)
+ return -ENXIO;
+
+ if (IS_ENABLED(CONFIG_TI_GPMC_DEBUG)) {
+ pr_info("GPMC CS%d CLK period is %lu ns (div %d)\n",
+ cs, (div * gpmc_get_fclk_period()) / 1000, div);
+ }
+
+ gpmc_cs_bool_timings(cs, &t->bool_timings);
+ gpmc_cs_show_timings(cs, "after gpmc_set_timings");
+
+ return 0;
+}
+
+static int gpmc_cs_set_memconf(int cs, resource_size_t base, u32 size)
+{
+ u32 l;
+ u32 mask;
+
+ /*
+ * Ensure that base address is aligned on a
+ * boundary equal to or greater than size.
+ */
+ if (base & (size - 1))
+ return -EINVAL;
+
+ base >>= GPMC_CHUNK_SHIFT;
+ mask = (1 << GPMC_SECTION_SHIFT) - size;
+ mask >>= GPMC_CHUNK_SHIFT;
+ mask <<= GPMC_CONFIG7_MASKADDRESS_OFFSET;
+
+ l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG7);
+ l &= ~GPMC_CONFIG7_MASK;
+ l |= base & GPMC_CONFIG7_BASEADDRESS_MASK;
+ l |= mask & GPMC_CONFIG7_MASKADDRESS_MASK;
+ l |= GPMC_CONFIG7_CSVALID;
+ gpmc_cs_write_reg(cs, GPMC_CS_CONFIG7, l);
+
+ return 0;
+}
+
+static void gpmc_cs_enable_mem(int cs)
+{
+ u32 l;
+
+ l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG7);
+ l |= GPMC_CONFIG7_CSVALID;
+ gpmc_cs_write_reg(cs, GPMC_CS_CONFIG7, l);
+}
+
+static void gpmc_cs_disable_mem(int cs)
+{
+ u32 l;
+
+ l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG7);
+ l &= ~GPMC_CONFIG7_CSVALID;
+ gpmc_cs_write_reg(cs, GPMC_CS_CONFIG7, l);
+}
+
+static void gpmc_cs_set_reserved(int cs, int reserved)
+{
+ struct gpmc_cs_data *gpmc = &gpmc_cs[cs];
+
+ gpmc->flags |= GPMC_CS_RESERVED;
+}
+
+static bool gpmc_cs_reserved(int cs)
+{
+ struct gpmc_cs_data *gpmc = &gpmc_cs[cs];
+
+ return gpmc->flags & GPMC_CS_RESERVED;
+}
+
+static unsigned long gpmc_mem_align(unsigned long size)
+{
+ int order;
+
+ size = (size - 1) >> (GPMC_CHUNK_SHIFT - 1);
+ order = GPMC_CHUNK_SHIFT - 1;
+ do {
+ size >>= 1;
+ order++;
+ } while (size);
+ size = 1 << order;
+ return size;
+}
+
+static int gpmc_cs_request(ofnode node, int cs, struct resource *res)
+{
+ int r = -1;
+ u32 size;
+ resource_size_t addr_base = res->start;
+
+ if (cs >= gpmc_cs_num) {
+ pr_err("%s: requested chip-select is disabled\n", __func__);
+ return -ENODEV;
+ }
+
+ size = gpmc_mem_align(resource_size(res));
+ if (size > (1 << GPMC_SECTION_SHIFT))
+ return -ENOMEM;
+
+ if (gpmc_cs_reserved(cs)) {
+ r = -EBUSY;
+ goto out;
+ }
+
+ if (addr_base & (SZ_16M - 1)) {
+ pr_err("CS region should be aligned to 16M boundary\n");
+ goto out;
+ }
+
+ /* Disable CS while changing base address and size mask */
+ gpmc_cs_disable_mem(cs);
+
+ r = gpmc_cs_set_memconf(cs, addr_base, size);
+ if (r < 0)
+ goto out;
+
+ /* Enable CS */
+ gpmc_cs_enable_mem(cs);
+ gpmc_cs_set_reserved(cs, 1);
+out:
+ return r;
+}
+
+static void gpmc_cs_free(int cs)
+{
+ if (cs >= gpmc_cs_num || cs < 0 || !gpmc_cs_reserved(cs)) {
+ pr_warn("Trying to free non-reserved GPMC CS%d\n", cs);
+ return;
+ }
+
+ gpmc_cs_disable_mem(cs);
+ gpmc_cs_set_reserved(cs, 0);
+}
+
+/**
+ * gpmc_configure - write request to configure gpmc
+ * @cmd: command type
+ * @wval: value to write
+ * @return status of the operation
+ */
+static int gpmc_configure(int cmd, int wval)
+{
+ u32 regval;
+
+ switch (cmd) {
+ case GPMC_CONFIG_WP:
+ regval = gpmc_read_reg(GPMC_CONFIG);
+ if (wval)
+ regval &= ~GPMC_CONFIG_WRITEPROTECT; /* WP is ON */
+ else
+ regval |= GPMC_CONFIG_WRITEPROTECT; /* WP is OFF */
+ gpmc_write_reg(GPMC_CONFIG, regval);
+ break;
+
+ default:
+ pr_err("%s: command not supported\n", __func__);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/**
+ * gpmc_cs_program_settings - programs non-timing related settings
+ * @cs: GPMC chip-select to program
+ * @p: pointer to GPMC settings structure
+ *
+ * Programs non-timing related settings for a GPMC chip-select, such as
+ * bus-width, burst configuration, etc. Function should be called once
+ * for each chip-select that is being used and must be called before
+ * calling gpmc_cs_set_timings() as timing parameters in the CONFIG1
+ * register will be initialised to zero by this function. Returns 0 on
+ * success and appropriate negative error code on failure.
+ */
+static int gpmc_cs_program_settings(int cs, struct gpmc_settings *p)
+{
+ u32 config1;
+
+ if (!p->device_width || p->device_width > GPMC_DEVWIDTH_16BIT) {
+ pr_err("%s: invalid width %d!", __func__, p->device_width);
+ return -EINVAL;
+ }
+
+ /* Address-data multiplexing not supported for NAND devices */
+ if (p->device_nand && p->mux_add_data) {
+ pr_err("%s: invalid configuration!\n", __func__);
+ return -EINVAL;
+ }
+
+ if (p->mux_add_data > GPMC_MUX_AD ||
+ (p->mux_add_data == GPMC_MUX_AAD &&
+ !(gpmc_capability & GPMC_HAS_MUX_AAD))) {
+ pr_err("%s: invalid multiplex configuration!\n", __func__);
+ return -EINVAL;
+ }
+
+ /* Page/burst mode supports lengths of 4, 8 and 16 bytes */
+ if (p->burst_read || p->burst_write) {
+ switch (p->burst_len) {
+ case GPMC_BURST_4:
+ case GPMC_BURST_8:
+ case GPMC_BURST_16:
+ break;
+ default:
+ pr_err("%s: invalid page/burst-length (%d)\n",
+ __func__, p->burst_len);
+ return -EINVAL;
+ }
+ }
+
+ if (p->wait_pin > gpmc_nr_waitpins) {
+ pr_err("%s: invalid wait-pin (%d)\n", __func__, p->wait_pin);
+ return -EINVAL;
+ }
+
+ config1 = GPMC_CONFIG1_DEVICESIZE((p->device_width - 1));
+
+ if (p->sync_read)
+ config1 |= GPMC_CONFIG1_READTYPE_SYNC;
+ if (p->sync_write)
+ config1 |= GPMC_CONFIG1_WRITETYPE_SYNC;
+ if (p->wait_on_read)
+ config1 |= GPMC_CONFIG1_WAIT_READ_MON;
+ if (p->wait_on_write)
+ config1 |= GPMC_CONFIG1_WAIT_WRITE_MON;
+ if (p->wait_on_read || p->wait_on_write)
+ config1 |= GPMC_CONFIG1_WAIT_PIN_SEL(p->wait_pin);
+ if (p->device_nand)
+ config1 |= GPMC_CONFIG1_DEVICETYPE(GPMC_DEVICETYPE_NAND);
+ if (p->mux_add_data)
+ config1 |= GPMC_CONFIG1_MUXTYPE(p->mux_add_data);
+ if (p->burst_read)
+ config1 |= GPMC_CONFIG1_READMULTIPLE_SUPP;
+ if (p->burst_write)
+ config1 |= GPMC_CONFIG1_WRITEMULTIPLE_SUPP;
+ if (p->burst_read || p->burst_write) {
+ config1 |= GPMC_CONFIG1_PAGE_LEN(p->burst_len >> 3);
+ config1 |= p->burst_wrap ? GPMC_CONFIG1_WRAPBURST_SUPP : 0;
+ }
+
+ gpmc_cs_write_reg(cs, GPMC_CS_CONFIG1, config1);
+
+ return 0;
+}
+
+static void gpmc_cs_set_name(int cs, const char *name)
+{
+ struct gpmc_cs_data *gpmc = &gpmc_cs[cs];
+
+ gpmc->name = name;
+}
+
+static const char *gpmc_cs_get_name(int cs)
+{
+ struct gpmc_cs_data *gpmc = &gpmc_cs[cs];
+
+ return gpmc->name;
+}
+
+/**
+ * gpmc_read_settings_dt - read gpmc settings from device-tree
+ * @np: pointer to device-tree node for a gpmc child device
+ * @p: pointer to gpmc settings structure
+ *
+ * Reads the GPMC settings for a GPMC child device from device-tree and
+ * stores them in the GPMC settings structure passed. The GPMC settings
+ * structure is initialised to zero by this function and so any
+ * previously stored settings will be cleared.
+ */
+static void gpmc_read_settings_dt(ofnode np, struct gpmc_settings *p)
+{
+ memset(p, 0, sizeof(struct gpmc_settings));
+
+ p->sync_read = ofnode_read_bool(np, "gpmc,sync-read");
+ p->sync_write = ofnode_read_bool(np, "gpmc,sync-write");
+ ofnode_read_u32(np, "gpmc,device-width", &p->device_width);
+ ofnode_read_u32(np, "gpmc,mux-add-data", &p->mux_add_data);
+
+ if (!ofnode_read_u32(np, "gpmc,burst-length", &p->burst_len)) {
+ p->burst_wrap = ofnode_read_bool(np, "gpmc,burst-wrap");
+ p->burst_read = ofnode_read_bool(np, "gpmc,burst-read");
+ p->burst_write = ofnode_read_bool(np, "gpmc,burst-write");
+ if (!p->burst_read && !p->burst_write)
+ pr_warn("%s: page/burst-length set but not used!\n",
+ __func__);
+ }
+
+ if (!ofnode_read_u32(np, "gpmc,wait-pin", &p->wait_pin)) {
+ p->wait_on_read = ofnode_read_bool(np,
+ "gpmc,wait-on-read");
+ p->wait_on_write = ofnode_read_bool(np,
+ "gpmc,wait-on-write");
+ if (!p->wait_on_read && !p->wait_on_write)
+ pr_debug("%s: rd/wr wait monitoring not enabled!\n",
+ __func__);
+ }
+}
+
+static void gpmc_read_timings_dt(ofnode np,
+ struct gpmc_timings *gpmc_t)
+{
+ struct gpmc_bool_timings *p;
+
+ if (!gpmc_t)
+ return;
+
+ memset(gpmc_t, 0, sizeof(*gpmc_t));
+
+ /* minimum clock period for syncronous mode */
+ ofnode_read_u32(np, "gpmc,sync-clk-ps", &gpmc_t->sync_clk);
+
+ /* chip select timtings */
+ ofnode_read_u32(np, "gpmc,cs-on-ns", &gpmc_t->cs_on);
+ ofnode_read_u32(np, "gpmc,cs-rd-off-ns", &gpmc_t->cs_rd_off);
+ ofnode_read_u32(np, "gpmc,cs-wr-off-ns", &gpmc_t->cs_wr_off);
+
+ /* ADV signal timings */
+ ofnode_read_u32(np, "gpmc,adv-on-ns", &gpmc_t->adv_on);
+ ofnode_read_u32(np, "gpmc,adv-rd-off-ns", &gpmc_t->adv_rd_off);
+ ofnode_read_u32(np, "gpmc,adv-wr-off-ns", &gpmc_t->adv_wr_off);
+ ofnode_read_u32(np, "gpmc,adv-aad-mux-on-ns",
+ &gpmc_t->adv_aad_mux_on);
+ ofnode_read_u32(np, "gpmc,adv-aad-mux-rd-off-ns",
+ &gpmc_t->adv_aad_mux_rd_off);
+ ofnode_read_u32(np, "gpmc,adv-aad-mux-wr-off-ns",
+ &gpmc_t->adv_aad_mux_wr_off);
+
+ /* WE signal timings */
+ ofnode_read_u32(np, "gpmc,we-on-ns", &gpmc_t->we_on);
+ ofnode_read_u32(np, "gpmc,we-off-ns", &gpmc_t->we_off);
+
+ /* OE signal timings */
+ ofnode_read_u32(np, "gpmc,oe-on-ns", &gpmc_t->oe_on);
+ ofnode_read_u32(np, "gpmc,oe-off-ns", &gpmc_t->oe_off);
+ ofnode_read_u32(np, "gpmc,oe-aad-mux-on-ns",
+ &gpmc_t->oe_aad_mux_on);
+ ofnode_read_u32(np, "gpmc,oe-aad-mux-off-ns",
+ &gpmc_t->oe_aad_mux_off);
+
+ /* access and cycle timings */
+ ofnode_read_u32(np, "gpmc,page-burst-access-ns",
+ &gpmc_t->page_burst_access);
+ ofnode_read_u32(np, "gpmc,access-ns", &gpmc_t->access);
+ ofnode_read_u32(np, "gpmc,rd-cycle-ns", &gpmc_t->rd_cycle);
+ ofnode_read_u32(np, "gpmc,wr-cycle-ns", &gpmc_t->wr_cycle);
+ ofnode_read_u32(np, "gpmc,bus-turnaround-ns",
+ &gpmc_t->bus_turnaround);
+ ofnode_read_u32(np, "gpmc,cycle2cycle-delay-ns",
+ &gpmc_t->cycle2cycle_delay);
+ ofnode_read_u32(np, "gpmc,wait-monitoring-ns",
+ &gpmc_t->wait_monitoring);
+ ofnode_read_u32(np, "gpmc,clk-activation-ns",
+ &gpmc_t->clk_activation);
+
+ /* only applicable to OMAP3+ */
+ ofnode_read_u32(np, "gpmc,wr-access-ns", &gpmc_t->wr_access);
+ ofnode_read_u32(np, "gpmc,wr-data-mux-bus-ns",
+ &gpmc_t->wr_data_mux_bus);
+
+ /* bool timing parameters */
+ p = &gpmc_t->bool_timings;
+
+ p->cycle2cyclediffcsen =
+ ofnode_read_bool(np, "gpmc,cycle2cycle-diffcsen");
+ p->cycle2cyclesamecsen =
+ ofnode_read_bool(np, "gpmc,cycle2cycle-samecsen");
+ p->we_extra_delay = ofnode_read_bool(np, "gpmc,we-extra-delay");
+ p->oe_extra_delay = ofnode_read_bool(np, "gpmc,oe-extra-delay");
+ p->adv_extra_delay = ofnode_read_bool(np, "gpmc,adv-extra-delay");
+ p->cs_extra_delay = ofnode_read_bool(np, "gpmc,cs-extra-delay");
+ p->time_para_granularity =
+ ofnode_read_bool(np, "gpmc,time-para-granularity");
+}
+
+/**
+ * gpmc_probe_generic_child - configures the gpmc for a child device
+ * @dev: pointer to gpmc platform device
+ * @child: pointer to device-tree node for child device
+ *
+ * Allocates and configures a GPMC chip-select for a child device.
+ * Returns 0 on success and appropriate negative error code on failure.
+ */
+static int gpmc_probe_generic_child(struct udevice *dev,
+ ofnode child)
+{
+ struct gpmc_settings gpmc_s;
+ struct gpmc_timings gpmc_t;
+ struct resource res;
+ const char *name;
+ int ret;
+ u32 val, cs;
+
+ if (ofnode_read_u32(child, "reg", &cs) < 0) {
+ dev_err(dev, "can't get reg property of child %s\n",
+ ofnode_get_name(child));
+ return -ENODEV;
+ }
+
+ if (ofnode_read_resource(child, 0, &res) < 0) {
+ dev_err(dev, "%s has malformed 'reg' property\n",
+ ofnode_get_name(child));
+ return -ENODEV;
+ }
+
+ /*
+ * Check if we have multiple instances of the same device
+ * on a single chip select. If so, use the already initialized
+ * timings.
+ */
+ name = gpmc_cs_get_name(cs);
+ if (name && !strcmp(name, ofnode_get_name(child)))
+ goto no_timings;
+
+ ret = gpmc_cs_request(child, cs, &res);
+ if (ret < 0) {
+ dev_err(dev, "cannot request GPMC CS %d\n", cs);
+ return ret;
+ }
+ gpmc_cs_set_name(cs, ofnode_get_name(child));
+
+ gpmc_read_settings_dt(child, &gpmc_s);
+ gpmc_read_timings_dt(child, &gpmc_t);
+
+ /*
+ * For some GPMC devices we still need to rely on the bootloader
+ * timings because the devices can be connected via FPGA.
+ * REVISIT: Add timing support from slls644g.pdf.
+ */
+ if (!gpmc_t.cs_rd_off) {
+ pr_warn("enable GPMC debug to configure .dts timings for CS%i\n",
+ cs);
+ gpmc_cs_show_timings(cs,
+ "please add GPMC bootloader timings to .dts");
+ goto no_timings;
+ }
+
+ /* CS must be disabled while making changes to gpmc configuration */
+ gpmc_cs_disable_mem(cs);
+
+ if (!ofnode_read_u32(child, "nand-bus-width", &val)) {
+ /* NAND specific setup */
+ ofnode_read_u32(child, "nand-bus-width", &val);
+ switch (val) {
+ case 8:
+ gpmc_s.device_width = GPMC_DEVWIDTH_8BIT;
+ break;
+ case 16:
+ gpmc_s.device_width = GPMC_DEVWIDTH_16BIT;
+ break;
+ default:
+ dev_err(dev, "%s: invalid 'nand-bus-width'\n",
+ ofnode_get_name(child));
+ ret = -EINVAL;
+ goto err;
+ }
+
+ /* disable write protect */
+ gpmc_configure(GPMC_CONFIG_WP, 0);
+ gpmc_s.device_nand = true;
+ } else {
+ ret = ofnode_read_u32(child, "bank-width",
+ &gpmc_s.device_width);
+ if (ret < 0 && !gpmc_s.device_width) {
+ dev_err(dev,
+ "%s has no 'gpmc,device-width' property\n",
+ ofnode_get_name(child));
+ goto err;
+ }
+ }
+
+ gpmc_cs_show_timings(cs, "before gpmc_cs_program_settings");
+
+ ret = gpmc_cs_program_settings(cs, &gpmc_s);
+ if (ret < 0)
+ goto err;
+
+ ret = gpmc_cs_set_timings(cs, &gpmc_t, &gpmc_s);
+ if (ret) {
+ dev_err(dev, "failed to set gpmc timings for: %s\n",
+ ofnode_get_name(child));
+ goto err;
+ }
+
+ /* Clear limited address i.e. enable A26-A11 */
+ val = gpmc_read_reg(GPMC_CONFIG);
+ val &= ~GPMC_CONFIG_LIMITEDADDRESS;
+ gpmc_write_reg(GPMC_CONFIG, val);
+
+ /* Enable CS region */
+ gpmc_cs_enable_mem(cs);
+
+no_timings:
+
+ return 0;
+
+err:
+ gpmc_cs_free(cs);
+
+ return ret;
+}
+
+static void gpmc_probe_dt_children(struct udevice *dev)
+{
+ int ret;
+ ofnode child;
+
+ ofnode_for_each_subnode(child, dev_ofnode(dev)) {
+ ret = gpmc_probe_generic_child(dev, child);
+ if (ret) {
+ dev_err(dev, "Cannot parse child %s:%d",
+ ofnode_get_name(child), ret);
+ }
+ }
+}
+
+static int gpmc_parse_dt(struct udevice *dev, struct ti_gpmc *gpmc)
+{
+ int ret;
+ u32 val;
+
+ ret = ofnode_read_u32(dev_ofnode(dev), "gpmc,num-cs",
+ &val);
+ if (ret < 0) {
+ pr_err("%s: number of chip-selects not defined\n", __func__);
+ return ret;
+ } else if (val < 1) {
+ pr_err("%s: all chip-selects are disabled\n", __func__);
+ return -EINVAL;
+ } else if (val > GPMC_CS_NUM) {
+ pr_err("%s: number of supported chip-selects cannot be > %d\n",
+ __func__, GPMC_CS_NUM);
+ return -EINVAL;
+ }
+
+ gpmc->cs_num = val;
+ gpmc_cs_num = val;
+
+ ret = ofnode_read_u32(dev_ofnode(dev), "gpmc,num-waitpins",
+ &gpmc->nr_waitpins);
+ if (ret < 0) {
+ pr_err("%s: number of wait pins not found!\n", __func__);
+ return ret;
+ }
+
+ gpmc_nr_waitpins = gpmc->nr_waitpins;
+
+ return 0;
+}
+
+static int gpmc_probe(struct udevice *dev)
+{
+ struct ti_gpmc *priv = dev_get_priv(dev);
+ int ret;
+ struct resource res;
+
+ ret = dev_read_resource_byname(dev, "cfg", &res);
+ if (ret) {
+ /* Legacy DT */
+ dev_read_resource(dev, 0, &res);
+ priv->base = devm_ioremap(dev, res.start, resource_size(&res));
+
+ priv->data.start = GPMC_MEM_START;
+ priv->data.end = GPMC_MEM_END;
+ } else {
+ priv->base = devm_ioremap(dev, res.start, resource_size(&res));
+ ret = dev_read_resource_byname(dev, "data", &res);
+ if (ret)
+ return -ENOENT;
+
+ priv->data = res;
+ }
+
+ if (!priv->base)
+ return -ENOMEM;
+
+ gpmc_cfg = (struct gpmc *)priv->base;
+ gpmc_base = priv->base;
+
+ priv->l3_clk = devm_clk_get(dev, "fck");
+ if (IS_ERR(priv->l3_clk))
+ return PTR_ERR(priv->l3_clk);
+
+ if (!clk_get_rate(priv->l3_clk))
+ return -EINVAL;
+
+ gpmc_l3_clk = priv->l3_clk;
+
+ ret = gpmc_parse_dt(dev, priv);
+ if (ret)
+ return ret;
+
+ priv->capability_flags = dev->driver->of_match->data;
+ gpmc_capability = priv->capability_flags;
+
+ gpmc_probe_dt_children(dev);
+
+ return 0;
+}
+
+#define GPMC_DATA_REV2_4 0
+#define GPMC_DATA_REV5 (GPMC_HAS_WR_ACCESS | GPMC_HAS_WR_DATA_MUX_BUS)
+#define GPMC_DATA_REV6 (GPMC_HAS_WR_ACCESS | GPMC_HAS_WR_DATA_MUX_BUS | GPMC_HAS_MUX_AAD)
+
+static const struct udevice_id gpmc_dt_ids[] = {
+ { .compatible = "ti,am64-gpmc", .data = GPMC_DATA_REV6, },
+ { .compatible = "ti,am3352-gpmc", .data = GPMC_DATA_REV5, },
+ { .compatible = "ti,omap2420-gpmc", .data = GPMC_DATA_REV2_4, },
+ { .compatible = "ti,omap2430-gpmc", .data = GPMC_DATA_REV2_4, },
+ { .compatible = "ti,omap3430-gpmc", .data = GPMC_DATA_REV5, },
+ { .compatible = "ti,omap4430-gpmc", .data = GPMC_DATA_REV6, },
+ { } /* sentinel */
+};
+
+U_BOOT_DRIVER(ti_gpmc) = {
+ .name = "ti-gpmc",
+ .id = UCLASS_MEMORY,
+ .of_match = gpmc_dt_ids,
+ .probe = gpmc_probe,
+ .flags = DM_FLAG_ALLOC_PRIV_DMA,
+};
diff --git a/drivers/memory/ti-gpmc.h b/drivers/memory/ti-gpmc.h
new file mode 100644
index 0000000000..90f8e656c8
--- /dev/null
+++ b/drivers/memory/ti-gpmc.h
@@ -0,0 +1,298 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Texas Instruments GPMC Driver
+ *
+ * Copyright (C) 2021 Texas Instruments Incorporated - http://www.ti.com/
+ */
+
+/* GPMC register offsets */
+#define GPMC_REVISION 0x00
+#define GPMC_SYSCONFIG 0x10
+#define GPMC_SYSSTATUS 0x14
+#define GPMC_IRQSTATUS 0x18
+#define GPMC_IRQENABLE 0x1c
+#define GPMC_TIMEOUT_CONTROL 0x40
+#define GPMC_ERR_ADDRESS 0x44
+#define GPMC_ERR_TYPE 0x48
+#define GPMC_CONFIG 0x50
+#define GPMC_STATUS 0x54
+#define GPMC_PREFETCH_CONFIG1 0x1e0
+#define GPMC_PREFETCH_CONFIG2 0x1e4
+#define GPMC_PREFETCH_CONTROL 0x1ec
+#define GPMC_PREFETCH_STATUS 0x1f0
+#define GPMC_ECC_CONFIG 0x1f4
+#define GPMC_ECC_CONTROL 0x1f8
+#define GPMC_ECC_SIZE_CONFIG 0x1fc
+#define GPMC_ECC1_RESULT 0x200
+#define GPMC_ECC_BCH_RESULT_0 0x240 /* not available on OMAP2 */
+#define GPMC_ECC_BCH_RESULT_1 0x244 /* not available on OMAP2 */
+#define GPMC_ECC_BCH_RESULT_2 0x248 /* not available on OMAP2 */
+#define GPMC_ECC_BCH_RESULT_3 0x24c /* not available on OMAP2 */
+#define GPMC_ECC_BCH_RESULT_4 0x300 /* not available on OMAP2 */
+#define GPMC_ECC_BCH_RESULT_5 0x304 /* not available on OMAP2 */
+#define GPMC_ECC_BCH_RESULT_6 0x308 /* not available on OMAP2 */
+
+/* GPMC ECC control settings */
+#define GPMC_ECC_CTRL_ECCCLEAR 0x100
+#define GPMC_ECC_CTRL_ECCDISABLE 0x000
+#define GPMC_ECC_CTRL_ECCREG1 0x001
+#define GPMC_ECC_CTRL_ECCREG2 0x002
+#define GPMC_ECC_CTRL_ECCREG3 0x003
+#define GPMC_ECC_CTRL_ECCREG4 0x004
+#define GPMC_ECC_CTRL_ECCREG5 0x005
+#define GPMC_ECC_CTRL_ECCREG6 0x006
+#define GPMC_ECC_CTRL_ECCREG7 0x007
+#define GPMC_ECC_CTRL_ECCREG8 0x008
+#define GPMC_ECC_CTRL_ECCREG9 0x009
+
+#define GPMC_CONFIG_LIMITEDADDRESS BIT(1)
+
+#define GPMC_STATUS_EMPTYWRITEBUFFERSTATUS BIT(0)
+
+#define GPMC_CONFIG2_CSEXTRADELAY BIT(7)
+#define GPMC_CONFIG3_ADVEXTRADELAY BIT(7)
+#define GPMC_CONFIG4_OEEXTRADELAY BIT(7)
+#define GPMC_CONFIG4_WEEXTRADELAY BIT(23)
+#define GPMC_CONFIG6_CYCLE2CYCLEDIFFCSEN BIT(6)
+#define GPMC_CONFIG6_CYCLE2CYCLESAMECSEN BIT(7)
+
+#define GPMC_CS0_OFFSET 0x60
+#define GPMC_CS_SIZE 0x30
+#define GPMC_BCH_SIZE 0x10
+
+/*
+ * The first 1MB of GPMC address space is typically mapped to
+ * the internal ROM. Never allocate the first page, to
+ * facilitate bug detection; even if we didn't boot from ROM.
+ * As GPMC minimum partition size is 16MB we can only start from
+ * there.
+ */
+#define GPMC_MEM_START 0x1000000
+#define GPMC_MEM_END 0x3FFFFFFF
+
+#define GPMC_CHUNK_SHIFT 24 /* 16 MB */
+#define GPMC_SECTION_SHIFT 28 /* 128 MB */
+
+#define CS_NUM_SHIFT 24
+#define ENABLE_PREFETCH (0x1 << 7)
+#define DMA_MPU_MODE 2
+
+#define GPMC_REVISION_MAJOR(l) (((l) >> 4) & 0xf)
+#define GPMC_REVISION_MINOR(l) ((l) & 0xf)
+
+#define GPMC_HAS_WR_ACCESS 0x1
+#define GPMC_HAS_WR_DATA_MUX_BUS 0x2
+#define GPMC_HAS_MUX_AAD 0x4
+
+#define GPMC_NR_WAITPINS 4
+
+#define GPMC_CS_CONFIG1 0x00
+#define GPMC_CS_CONFIG2 0x04
+#define GPMC_CS_CONFIG3 0x08
+#define GPMC_CS_CONFIG4 0x0c
+#define GPMC_CS_CONFIG5 0x10
+#define GPMC_CS_CONFIG6 0x14
+#define GPMC_CS_CONFIG7 0x18
+#define GPMC_CS_NAND_COMMAND 0x1c
+#define GPMC_CS_NAND_ADDRESS 0x20
+#define GPMC_CS_NAND_DATA 0x24
+
+/* Control Commands */
+#define GPMC_CONFIG_RDY_BSY 0x00000001
+#define GPMC_CONFIG_DEV_SIZE 0x00000002
+#define GPMC_CONFIG_DEV_TYPE 0x00000003
+
+#define GPMC_CONFIG_WP 0x00000005
+
+#define GPMC_CONFIG1_WRAPBURST_SUPP BIT(31)
+#define GPMC_CONFIG1_READMULTIPLE_SUPP BIT(30)
+#define GPMC_CONFIG1_READTYPE_ASYNC (0 << 29)
+#define GPMC_CONFIG1_READTYPE_SYNC BIT(29)
+#define GPMC_CONFIG1_WRITEMULTIPLE_SUPP BIT(28)
+#define GPMC_CONFIG1_WRITETYPE_ASYNC (0 << 27)
+#define GPMC_CONFIG1_WRITETYPE_SYNC BIT(27)
+#define GPMC_CONFIG1_CLKACTIVATIONTIME(val) (((val) & 3) << 25)
+/** CLKACTIVATIONTIME Max Ticks */
+#define GPMC_CONFIG1_CLKACTIVATIONTIME_MAX 2
+#define GPMC_CONFIG1_PAGE_LEN(val) (((val) & 3) << 23)
+/** ATTACHEDDEVICEPAGELENGTH Max Value */
+#define GPMC_CONFIG1_ATTACHEDDEVICEPAGELENGTH_MAX 2
+#define GPMC_CONFIG1_WAIT_READ_MON BIT(22)
+#define GPMC_CONFIG1_WAIT_WRITE_MON BIT(21)
+#define GPMC_CONFIG1_WAIT_MON_TIME(val) (((val) & 3) << 18)
+/** WAITMONITORINGTIME Max Ticks */
+#define GPMC_CONFIG1_WAITMONITORINGTIME_MAX 2
+#define GPMC_CONFIG1_WAIT_PIN_SEL(val) (((val) & 3) << 16)
+#define GPMC_CONFIG1_DEVICESIZE(val) (((val) & 3) << 12)
+#define GPMC_CONFIG1_DEVICESIZE_16 GPMC_CONFIG1_DEVICESIZE(1)
+/** DEVICESIZE Max Value */
+#define GPMC_CONFIG1_DEVICESIZE_MAX 1
+#define GPMC_CONFIG1_DEVICETYPE(val) (((val) & 3) << 10)
+#define GPMC_CONFIG1_DEVICETYPE_NOR GPMC_CONFIG1_DEVICETYPE(0)
+#define GPMC_CONFIG1_MUXTYPE(val) (((val) & 3) << 8)
+#define GPMC_CONFIG1_TIME_PARA_GRAN BIT(4)
+#define GPMC_CONFIG1_FCLK_DIV(val) ((val) & 3)
+#define GPMC_CONFIG1_FCLK_DIV2 (GPMC_CONFIG1_FCLK_DIV(1))
+#define GPMC_CONFIG1_FCLK_DIV3 (GPMC_CONFIG1_FCLK_DIV(2))
+#define GPMC_CONFIG1_FCLK_DIV4 (GPMC_CONFIG1_FCLK_DIV(3))
+#define GPMC_CONFIG7_CSVALID BIT(6)
+
+#define GPMC_CONFIG7_BASEADDRESS_MASK 0x3f
+#define GPMC_CONFIG7_CSVALID_MASK BIT(6)
+#define GPMC_CONFIG7_MASKADDRESS_OFFSET 8
+#define GPMC_CONFIG7_MASKADDRESS_MASK (0xf << GPMC_CONFIG7_MASKADDRESS_OFFSET)
+/* All CONFIG7 bits except reserved bits */
+#define GPMC_CONFIG7_MASK (GPMC_CONFIG7_BASEADDRESS_MASK | \
+ GPMC_CONFIG7_CSVALID_MASK | \
+ GPMC_CONFIG7_MASKADDRESS_MASK)
+
+#define GPMC_DEVICETYPE_NOR 0
+#define GPMC_DEVICETYPE_NAND 2
+#define GPMC_CONFIG_WRITEPROTECT 0x00000010
+#define WR_RD_PIN_MONITORING 0x00600000
+
+/* ECC commands */
+#define GPMC_ECC_READ 0 /* Reset Hardware ECC for read */
+#define GPMC_ECC_WRITE 1 /* Reset Hardware ECC for write */
+#define GPMC_ECC_READSYN 2 /* Reset before syndrom is read back */
+
+#define GPMC_NR_NAND_IRQS 2 /* number of NAND specific IRQs */
+
+/* bool type time settings */
+struct gpmc_bool_timings {
+ bool cycle2cyclediffcsen;
+ bool cycle2cyclesamecsen;
+ bool we_extra_delay;
+ bool oe_extra_delay;
+ bool adv_extra_delay;
+ bool cs_extra_delay;
+ bool time_para_granularity;
+};
+
+/*
+ * Note that all values in this struct are in nanoseconds except sync_clk
+ * (which is in picoseconds), while the register values are in gpmc_fck cycles.
+ */
+struct gpmc_timings {
+ /* Minimum clock period for synchronous mode (in picoseconds) */
+ u32 sync_clk;
+
+ /* Chip-select signal timings corresponding to GPMC_CS_CONFIG2 */
+ u32 cs_on; /* Assertion time */
+ u32 cs_rd_off; /* Read deassertion time */
+ u32 cs_wr_off; /* Write deassertion time */
+
+ /* ADV signal timings corresponding to GPMC_CONFIG3 */
+ u32 adv_on; /* Assertion time */
+ u32 adv_rd_off; /* Read deassertion time */
+ u32 adv_wr_off; /* Write deassertion time */
+ u32 adv_aad_mux_on; /* ADV assertion time for AAD */
+ u32 adv_aad_mux_rd_off; /* ADV read deassertion time for AAD */
+ u32 adv_aad_mux_wr_off; /* ADV write deassertion time for AAD */
+
+ /* WE signals timings corresponding to GPMC_CONFIG4 */
+ u32 we_on; /* WE assertion time */
+ u32 we_off; /* WE deassertion time */
+
+ /* OE signals timings corresponding to GPMC_CONFIG4 */
+ u32 oe_on; /* OE assertion time */
+ u32 oe_off; /* OE deassertion time */
+ u32 oe_aad_mux_on; /* OE assertion time for AAD */
+ u32 oe_aad_mux_off; /* OE deassertion time for AAD */
+
+ /* Access time and cycle time timings corresponding to GPMC_CONFIG5 */
+ u32 page_burst_access; /* Multiple access word delay */
+ u32 access; /* Start-cycle to first data valid delay */
+ u32 rd_cycle; /* Total read cycle time */
+ u32 wr_cycle; /* Total write cycle time */
+
+ u32 bus_turnaround;
+ u32 cycle2cycle_delay;
+
+ u32 wait_monitoring;
+ u32 clk_activation;
+
+ /* The following are only on OMAP3430 */
+ u32 wr_access; /* WRACCESSTIME */
+ u32 wr_data_mux_bus; /* WRDATAONADMUXBUS */
+
+ struct gpmc_bool_timings bool_timings;
+};
+
+/* Device timings in picoseconds */
+struct gpmc_device_timings {
+ u32 t_ceasu; /* address setup to CS valid */
+ u32 t_avdasu; /* address setup to ADV valid */
+ /* XXX: try to combine t_avdp_r & t_avdp_w. Issue is
+ * of tusb using these timings even for sync whilst
+ * ideally for adv_rd/(wr)_off it should have considered
+ * t_avdh instead. This indirectly necessitates r/w
+ * variations of t_avdp as it is possible to have one
+ * sync & other async
+ */
+ u32 t_avdp_r; /* ADV low time (what about t_cer ?) */
+ u32 t_avdp_w;
+ u32 t_aavdh; /* address hold time */
+ u32 t_oeasu; /* address setup to OE valid */
+ u32 t_aa; /* access time from ADV assertion */
+ u32 t_iaa; /* initial access time */
+ u32 t_oe; /* access time from OE assertion */
+ u32 t_ce; /* access time from CS asertion */
+ u32 t_rd_cycle; /* read cycle time */
+ u32 t_cez_r; /* read CS deassertion to high Z */
+ u32 t_cez_w; /* write CS deassertion to high Z */
+ u32 t_oez; /* OE deassertion to high Z */
+ u32 t_weasu; /* address setup to WE valid */
+ u32 t_wpl; /* write assertion time */
+ u32 t_wph; /* write deassertion time */
+ u32 t_wr_cycle; /* write cycle time */
+
+ u32 clk;
+ u32 t_bacc; /* burst access valid clock to output delay */
+ u32 t_ces; /* CS setup time to clk */
+ u32 t_avds; /* ADV setup time to clk */
+ u32 t_avdh; /* ADV hold time from clk */
+ u32 t_ach; /* address hold time from clk */
+ u32 t_rdyo; /* clk to ready valid */
+
+ u32 t_ce_rdyz; /* XXX: description ?, or use t_cez instead */
+ u32 t_ce_avd; /* CS on to ADV on delay */
+
+ /* XXX: check the possibility of combining
+ * cyc_aavhd_oe & cyc_aavdh_we
+ */
+ u8 cyc_aavdh_oe;/* read address hold time in cycles */
+ u8 cyc_aavdh_we;/* write address hold time in cycles */
+ u8 cyc_oe; /* access time from OE assertion in cycles */
+ u8 cyc_wpl; /* write deassertion time in cycles */
+ u32 cyc_iaa; /* initial access time in cycles */
+
+ /* extra delays */
+ bool ce_xdelay;
+ bool avd_xdelay;
+ bool oe_xdelay;
+ bool we_xdelay;
+};
+
+#define GPMC_BURST_4 4 /* 4 word burst */
+#define GPMC_BURST_8 8 /* 8 word burst */
+#define GPMC_BURST_16 16 /* 16 word burst */
+#define GPMC_DEVWIDTH_8BIT 1 /* 8-bit device width */
+#define GPMC_DEVWIDTH_16BIT 2 /* 16-bit device width */
+#define GPMC_MUX_AAD 1 /* Addr-Addr-Data multiplex */
+#define GPMC_MUX_AD 2 /* Addr-Data multiplex */
+
+struct gpmc_settings {
+ bool burst_wrap; /* enables wrap bursting */
+ bool burst_read; /* enables read page/burst mode */
+ bool burst_write; /* enables write page/burst mode */
+ bool device_nand; /* device is NAND */
+ bool sync_read; /* enables synchronous reads */
+ bool sync_write; /* enables synchronous writes */
+ bool wait_on_read; /* monitor wait on reads */
+ bool wait_on_write; /* monitor wait on writes */
+ u32 burst_len; /* page/burst length */
+ u32 device_width; /* device bus width (8 or 16 bit) */
+ u32 mux_add_data; /* multiplex address & data */
+ u32 wait_pin; /* wait-pin to be used */
+};
diff --git a/include/linux/mtd/omap_gpmc.h b/include/linux/mtd/omap_gpmc.h
index 864b05e432..f08e700a1d 100644
--- a/include/linux/mtd/omap_gpmc.h
+++ b/include/linux/mtd/omap_gpmc.h
@@ -8,6 +8,9 @@
#ifndef __ASM_OMAP_GPMC_H
#define __ASM_OMAP_GPMC_H
+/* Maximum Number of Chip Selects */
+#define GPMC_CS_NUM 8
+
#define GPMC_BUF_EMPTY 0
#define GPMC_BUF_FULL 1
#define GPMC_MAX_SECTORS 8